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Sample records for machining edm process

  1. Analysis of aerosol emission and hazard evaluation of electrical discharge machining (EDM) process.

    PubMed

    Jose, Mathew; Sivapirakasam, S P; Surianarayanan, M

    2010-01-01

    The safety and environmental aspects of a manufacturing process are important due to increased environmental regulations and life quality. In this paper, the concentration of aerosols in the breathing zone of the operator of Electrical Discharge Machining (EDM), a commonly used non traditional manufacturing process is presented. The pattern of aerosol emissions from this process with varying process parameters such as peak current, pulse duration, dielectric flushing pressure and the level of dielectric was evaluated. Further, the HAZOP technique was employed to identify the inherent safety aspects and fire risk of the EDM process under different working conditions. The analysis of aerosol exposure showed that the concentration of aerosol was increased with increase in the peak current, pulse duration and dielectric level and was decreased with increase in the flushing pressure. It was also found that at higher values of peak current (7A) and pulse duration (520 micros), the concentration of aerosols at breathing zone of the operator was above the permissible exposure limit value for respirable particulates (5 mg/m(3)). HAZOP study of the EDM process showed that this process is vulnerable to fire and explosion hazards. A detailed discussion on preventing the fire and explosion hazard is presented in this paper. The emission and risk of fire of the EDM process can be minimized by selecting proper process parameters and employing appropriate control strategy. PMID:20720340

  2. Fast and stable electrical discharge machining (EDM)

    NASA Astrophysics Data System (ADS)

    Wu, Jianyang; Zhou, Ming; Xu, Xiaoyi; Yang, Jianwei; Zeng, Xiangwei; Xu, Donghui

    2016-05-01

    In order to improve EDM performances, the most important issue is to develop a highly stable control system. As a serious defect in EDM adaptive control system by minimum-variance control law, the occasional instability deterred its full applications in industries. This paper focuses on stabilizing EDM process by establishing a new minimum-variance and pole-placement coupled control law. Based on real-time estimation of EDM process model parameters, this adaptive control system directly controls electrode discharging cycle not only to follow a specified gap state for fast machining but also to track the dynamical response of a reference model for stabilizing EDM process. Confirmation experiment demonstrates that this control system can timely adjust electrode discharging cycle in terms of different machining situations quantified as a series of varied gap states to maintain a stable and fast fabrication. The adaptive control system by this newly developed control law exhibits its superior machining ability and capability of stabilizing sparking process to those of the adaptive control system by minimum-variance control law. The adaptive system has actually theoretically and technically solved the stability issue puzzled EDM circle for decades.

  3. Mechanical characterization of Cu-Zn wire electrode base used in EDM and study of influence of the process of machining on its properties

    SciTech Connect

    Sedjal, H. Amirat, B.; Aichour, M.; Marouf, T.; Chitroub, M.

    2015-03-30

    This work is part of a Research National project (PNR) carried out by the group of research of the engineering and material sciences laboratory of the polytechnic national school at Algiers in collaboration with company BCR, which relates to “the characterization of the wire intended for the EDM of matrices metal. The goal of this work is to bring metallographic explanations on the wire electrode used by the machine ROBOFIL 290P, mechanically characterized this wire as of knowing of advantage about the process of its manufacturing (wiredrawing, .) The methods of studies used are it micro Vickers pyramid hardness, the tensile test, optical microscopy and scan electronic microscopy SEM.

  4. Mechanical characterization of Cu-Zn wire electrode base used in EDM and study of influence of the process of machining on its properties

    NASA Astrophysics Data System (ADS)

    Sedjal, H.; Amirat, B.; Aichour, M.; Marouf, T.; Chitroub, M.

    2015-03-01

    This work is part of a Research National project (PNR) carried out by the group of research of the engineering and material sciences laboratory of the polytechnic national school at Algiers in collaboration with company BCR, which relates to "the characterization of the wire intended for the EDM of matrices metal. The goal of this work is to bring metallographic explanations on the wire electrode used by the machine ROBOFIL 290P, mechanically characterized this wire as of knowing of advantage about the process of its manufacturing (wiredrawing, .) The methods of studies used are it micro Vickers pyramid hardness, the tensile test, optical microscopy and scan electronic microscopy SEM.

  5. Evaluating the electrical discharge machining (EDM) parameters with using carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Sari, M. M.; Noordin, M. Y.; Brusa, E.

    2012-09-01

    Electrical discharge machining (EDM) is one of the most accurate non traditional manufacturing processes available for creating tiny apertures, complex or simple shapes and geometries within parts and assemblies. Performance of the EDM process is usually evaluated in terms of surface roughness, existence of cracks, voids and recast layer on the surface of product, after machining. Unfortunately, the high heat generated on the electrically discharged material during the EDM process decreases the quality of products. Carbon nanotubes display unexpected strength and unique electrical and thermal properties. Multi-wall carbon nanotubes are therefore on purpose added to the dielectric used in the EDM process to improve its performance when machining the AISI H13 tool steel, by means of copper electrodes. Some EDM parameters such as material removal rate, electrode wear rate, surface roughness and recast layer are here first evaluated, then compared to the outcome of EDM performed without using nanotubes mixed to the dielectric. Independent variables investigated are pulse on time, peak current and interval time. Experimental evidences show that EDM process operated by mixing multi-wall carbon nanotubes within the dielectric looks more efficient, particularly if machining parameters are set at low pulse of energy.

  6. A fatigue study of electrical discharge machine (EDM) strain-gage balance materials

    NASA Technical Reports Server (NTRS)

    Rhew, Ray D.

    1989-01-01

    A fatigue study was undertaken to determine how much electrical-discharge-machine (EDM) processing affected the fatigue life of balance materials: EDM and regular milling-machine (MM) samples were compared. Simulation of a typical balance stress configuration was devised for the fatigue testing in order to obtain results more closely related to balance situations. The fatigue testing of the EDM and MM specimens has indicated that the EDM technique does indeed reduce the fatigue life of 15-5PH steel, the first balance material tested. This conclusion was based on comparisons of the specimen fatigue lives with theoretical and manufacturer's data. Hence the EDM surface effects are detrimental to the fatigue life of this balance material.

  7. A study on the quality of micro-hole of Ti-6Al-4V by EDM process with on-machine measurement techniques

    NASA Astrophysics Data System (ADS)

    Li, Jun; Liu, Xiaoyu; Wei, Xingping; Zhao, Shiping

    2013-10-01

    A new on-machine measurement technique is proposed to observe the quality of micro-hole in micro Electrical Discharge Machining (EDM) progress. Images of micro-hole are captured by means of a simple configuration use a light-emitting diode (LED) illuminator, optical fiber, and a camera charge-coupled device (CCD).The device does not make contact with workpiece and acquire the image from the contour of the finished micro-hole. Because of using the optical fiber to transmit the real-time image, the device can woke in the narrow and small place. Based on the detected feature points, the geometrical features of the finished micro-hole such as its aperture can be obtained in real time. Meanwhile, the measuring result shows the micro-hole is whether or not qualified and can optimize the process parameters.

  8. Development of an Eco-Friendly Electrical Discharge Machine (E-EDM) Using TRIZ Approach

    NASA Astrophysics Data System (ADS)

    Sreebalaji, V. S.; Saravanan, R.

    Electrical Discharge Machine (EDM) is one of the non-traditional machining processes. EDM process is based on thermoelectric energy between the work and an electrode. A pulse discharge occurs in a small gap between the work piece and the electrode and removes the unwanted material from the parent metal through melting and vaporization. The electrode and the work piece must have an electrical conductivity in order to generate the spark. Dielectric fluid acts as a spark conductor, concentrating the energy to a very narrow region. There are various types of products can be produced and finished using EDM such as Moulds, Dies, Parts of Aerodynamics, Automotives and Surgical components. This research work reveals how an Eco friendly EDM (E-EDM) can be modeled to replace die electric fluid and introducing ozonised oxygen in to EDM to eliminate harmful effects generated while machining by using dielectric, to make pollution free machining environment through a new design of EEDM using TRIZ (a Russian acronym for Theory of Inventive Problem Solving) approach, since Eco friendly design is the need of the hour.

  9. Study on ultra-fine w-EDM with on-machine measurement-assisted

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong; Yang, Hong-Ye

    2011-01-01

    The purpose of this study was to develop the on-machine measurement techniques so as to precisely fabricate micro intricate part using ultra-fine w-EDM. The measurement-assisted approach which employs an automatic optical inspection (AOI) is incorporated to ultra-fine w-EDM process to on-machine detect the machining error for next re-machining. The AOI acquires the image through a high resolution CCD device from the contour of the workpiece after roughing in order to further process and recognize the image for determining the residual. This facilitates the on-machine error detection and compensation re-machining. The micro workpiece and electrode are not repositioned during machining. A fabrication for a micro probe of 30-μm diameter is rapidly machined and verified successfully. Based on the proposed technique, on-machine measurement with AOI has been realized satisfactorily.

  10. Study on ultra-fine w-EDM with on-machine measurement-assisted

    SciTech Connect

    Chen Shuntong; Yang Hongye

    2011-01-17

    The purpose of this study was to develop the on-machine measurement techniques so as to precisely fabricate micro intricate part using ultra-fine w-EDM. The measurement-assisted approach which employs an automatic optical inspection (AOI) is incorporated to ultra-fine w-EDM process to on-machine detect the machining error for next re-machining. The AOI acquires the image through a high resolution CCD device from the contour of the workpiece after roughing in order to further process and recognize the image for determining the residual. This facilitates the on-machine error detection and compensation re-machining. The micro workpiece and electrode are not repositioned during machining. A fabrication for a micro probe of 30-{mu}m diameter is rapidly machined and verified successfully. Based on the proposed technique, on-machine measurement with AOI has been realized satisfactorily.

  11. Positional accuracy study of a micro-EDM machine

    NASA Astrophysics Data System (ADS)

    Almond, Heather J. A.; Bhogal, Jagmohan; Allen, David M.

    1999-03-01

    Micro-electrodischarge machining is used to machine small features such as holes, cavities and slots with high aspect ratios in electrically-conductive materials for various applications including medical implants, printing devices, dies and spray nozzles. In this study, the positional accuracy of a micro-EDM machine was assessed while simulating the machining of an array of holes. The measurement involved the use of a diffraction grid plate and non-contact scanning head. This enabled various conclusions to be drawn as to the relative deviations experienced when machining small features such as (phi) 50 micrometers holes.

  12. Study of micro-electro discharge machining (micro-EDM) with on-machine measurement-assisted techniques

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong; Yang, Hong-Ye

    2011-06-01

    In this study on-machine measurement-assisted techniques are utilized in combination with micro-EDM to successfully machine intricate micro-parts. Two measurement approaches, automatic optical inspection (AOI) and critical contact measurement (CCM), are used on a previously built machine tool. AOI acquires the image from the contour of the machined workpiece and further processes the image to determine the finish allowance. CCM measures on-line the consumption of the microelectrode to create an accurate compensation rate. These two non-contact measurement techniques facilitate on-machine error detection and re-machining during micro-EDM. Significant work efficiency and preservation of machining accuracy are gained by having the workpiece and tool remain in place throughout machining procedures. A micro-probe with a diameter of 30 µm and a micro 3D engraving mold on a small tungsten steel ball are perfectly fabricated and verified, respectively.

  13. Vertical EDM (electric discharge machining) using modular programming

    SciTech Connect

    Fuller, J.E.

    1989-01-01

    The usual function of computer numerically controlled (CNC) machining programs is to specify a sequence of machining operations. When CNC is applied to electric discharge machining (EDM), the possibilities and needs are much greater. This paper describes a modular system of programming in which various functions are carried out by subroutines contained in the controller memory. The subroutines are made more versatile by using variables. Such functions as orbiting, cavity inspection, electrode wear measurement and compensation, and multiple cavities are possible. 3 refs., 9 figs.

  14. A machine vision system for micro-EDM based on linux

    NASA Astrophysics Data System (ADS)

    Guo, Rui; Zhao, Wansheng; Li, Gang; Li, Zhiyong; Zhang, Yong

    2006-11-01

    Due to the high precision and good surface quality that it can give, Electrical Discharge Machining (EDM) is potentially an important process for the fabrication of micro-tools and micro-components. However, a number of issues remain unsolved before micro-EDM becomes a reliable process with repeatable results. To deal with the difficulties in micro electrodes on-line fabrication and tool wear compensation, a micro-EDM machine vision system is developed with a Charge Coupled Device (CCD) camera, with an optical resolution of 1.61μm and an overall magnification of 113~729. Based on the Linux operating system, an image capturing program is developed with the V4L2 API, and an image processing program is exploited by using OpenCV. The contour of micro electrodes can be extracted by means of the Canny edge detector. Through the system calibration, the micro electrodes diameter can be measured on-line. Experiments have been carried out to prove its performance, and the reasons of measurement error are also analyzed.

  15. Fabrication Of Micro-Nozzles Via {mu}-EDM Process

    SciTech Connect

    Modica, F.; Trotta, G.; Fassi, I.

    2011-01-17

    Since traditional handling mechanisms have an unpredictable behavior at micro scale, micro-assembly is a bottleneck in the development of hybrid micro-systems, and the development of new approaches is strongly demanded. In this paper, a recent study of the fabrication of a ceramics vacuum micro-gripper to handle parts in the range of hundreds of microns (300-1000) is presented. Among the possible micro manufacturing processes, micro-EDM has been selected as proving to be a very competitive fabrication technology for the manufacturing of ultra miniature components and micro sized features. The influence of the process parameters on the machining performance of interest is firstly investigated; then, the experimental results on machining the micro gripper are presented, finally concluding remarks are given.

  16. EDM machinability of SiCw/Al composites

    NASA Technical Reports Server (NTRS)

    Ramulu, M.; Taya, M.

    1989-01-01

    Machinability of high temperature composites was investigated. Target materials, 15 and 25 vol pct SiC whisker-2124 aluminum composites, were machined by electrodischarge sinker machining and diamond saw. The machined surfaces of these metal matrix composites were examined by SEM and profilometry to determine the surface finish. Microhardness measurements were also performed on the as-machined composites.

  17. Traveling wire electrode increases productivity of Electrical Discharge Machining /EDM/ equipment

    NASA Technical Reports Server (NTRS)

    Kotora, J., Jr.; Smith, S. V.

    1967-01-01

    Traveling wire electrode on electrical discharge machining /EDM/ equipment reduces the time requirements for precision cutting. This device enables cutting with a minimum of lost material and without inducing stress beyond that inherent in the material. The use of wire increases accuracy and enables tighter tolerances to be maintained.

  18. Electrical discharge machining (EDM) of Inconel 718 by using copper electrode at higher peak current and pulse duration

    NASA Astrophysics Data System (ADS)

    Ahmad, S.; Lajis, M. A.

    2013-12-01

    This experimental work is an attempt to investigate the performance of Copper electrode when EDM of Nickel Based Super Alloy, Inconel 718 is at higher peak current and pulse duration. Peak current, Ip and pulse duration (pulse on-time), ton are selected as the most important electrical pulse parameters. In addition, their influence on material removal rate (MRR), electrode wear rate (EWR), and surface roughness (Ra) are experimentally investigated. The ranges of 10 mm diameter of Copper electrode are used to EDM of Inconel 718. After the experiments, MRR, EWR, and Ra of the machined surfaces need to be measured in order to evaluate the performance of the EDM process. In order to obtain high MRR, higher peak current in range of 20A to 40A and pulse duration in range of 200μs to 400μs were used. Experimental results have shown that machining at a highest peak current used of 40A and the lowest pulse duration of 200μs used for the experiment yields the highest material removal rate (MRR) with value 34.94 mm3/min, whereas machining at a peak current of 20A and pulse duration of 400μs yields the lowest electrode wear rate (EWR) with value -0.0101 mm3/min. The lowest surface roughness (Ra) is 8.53 μm achieved at a lowest peak current used of 20A and pulse duration of 200μs.

  19. Development of the Cylindrical Wire Electrical Discharge Machining Process.

    SciTech Connect

    McSpadden, SB

    2002-01-22

    Results of applying the wire Electrical Discharge Machining (EDM) process to generate precise cylindrical forms on hard, difficult-to-machine materials are presented. A precise, flexible, and corrosion-resistant underwater rotary spindle was designed and added to a conventional two-axis wire EDM machine to enable the generation of free-form cylindrical geometries. A detailed spindle error analysis identifies the major source of error at different frequency. The mathematical model for the material removal of cylindrical wire EDM process is derived. Experiments were conducted to explore the maximum material removal rate for cylindrical and 2D wire EDM of carbide and brass work-materials. Compared to the 2D wire EDM, higher maximum material removal rates may be achieved in the cylindrical wire EDM. This study also investigates the surface integrity and roundness of parts created by the cylindrical wire EDM process. For carbide parts, an arithmetic average surface roughness and roundness as low as 0.68 and 1.7 {micro}m, respectively, can be achieved. Surfaces of the cylindrical EDM parts were examined using Scanning Electron Microscopy (SEM) to identify the craters, sub-surface recast layers and heat-affected zones under various process parameters. This study has demonstrated that the cylindrical wire EDM process parameters can be adjusted to achieve either high material removal rate or good surface integrity.

  20. Investigation of the removing process of cathode material in micro-EDM using an atomistic-continuum model

    NASA Astrophysics Data System (ADS)

    Guo, Jianwen; Zhang, Guojun; Huang, Yu; Ming, Wuyi; Liu, Min; Huang, Hao

    2014-10-01

    In micro-electrical discharge machining (micro-EDM), the discharge duration is ultra-short, and both the electric action and the thermal action by the discharge channel play important roles in the removing process of cathode material. However, in most researches on the machining mechanism of micro-EDM, only the thermal action is concerned. In this article, a combined atomistic-continuum modeling method in which the two-temperature model and the molecular dynamics simulation model are integrated is used to construct the simulation model for cathode in single-discharge micro-EDM process. With this simulation model, removing processes of Cu cathode material in micro-EDM under pure thermal action, pure electric action and the combination of them are investigated in a simulative way. By analyzing evolutions of temperature, stress and micro-structure of material as well as the dynamical behaviors of material in the removing process, mechanisms of the cathode material removal and crater formation are revealed. In addition, the removing process of cathode material under the combination of pure thermal action and pure electric action is compared with those under the two pure actions respectively to analyze the interactive effect between the thermal action and the electric action.

  1. Electrical Discharge Machining.

    ERIC Educational Resources Information Center

    Montgomery, C. M.

    The manual is for use by students learning electrical discharge machining (EDM). It consists of eight units divided into several lessons, each designed to meet one of the stated objectives for the unit. The units deal with: introduction to and advantages of EDM, the EDM process, basic components of EDM, reaction between forming tool and workpiece,…

  2. Monitor For Electrical-Discharge Machining

    NASA Technical Reports Server (NTRS)

    Burley, Richard K.

    1993-01-01

    Circuit monitors electrical-discharge-machining (EDM) process to detect and prevent abnormal arcing, which can produce unacceptable "burn" marks on workpiece. When voltage between EDM electrode and workpiece behaves in manner indicative of abnormal arcing, relay made to switch off EDM power, which remains off until operator attends to EDM setup and resets monitor.

  3. Fabrication of high aspect ratio micro electrode by using EDM

    NASA Astrophysics Data System (ADS)

    Mejid Elsiti, Nagwa; Noordin, M. Y.; Umar Alkali, Adam

    2016-02-01

    The electrical discharge machining (EDM) process inherits characteristics that make it a promising micro-machining technique. Micro electrical discharge machining (micro- EDM) is a derived form of EDM, which is commonly used to manufacture micro and miniature parts and components by using the conventional electrical discharge machining fundamentals. Moving block electro discharge grinding (Moving BEDG) is one of the processes that can be used to fabricate micro-electrode. In this study, a conventional die sinker EDM machine was used to fabricate the micro-electrode. Modifications are made to the moving BEDG, which include changing the direction of movements and control gap in one electrode. Consequently current was controlled due to the use of roughing, semi-finishing and finishing parameters. Finally, a high aspect ratio micro-electrode with a diameter of 110.49μm and length of 6000μm was fabricated.

  4. Characterization of nanoparticles from abrasive waterjet machining and electrical discharge machining processes.

    PubMed

    Ling, Tsz Yan; Pui, David Y H

    2013-11-19

    Abrasive Waterjet Machining (AWM) and Electrical Discharge Machining (EDM) processes are found to produce nanoparticles during operation. Impacts of engineered nanoparticles released to the environment and biological system have caused much concern. Similarly, the nanoparticles unintentionally produced by the AWM and EDM can lead to comparable effects. By application of the Nanoparticle Tracking Analysis (NTA) technique, the size distribution and concentration of nanoparticles in the water used in AWM and EDM were measured. The particles generally have a peak size of 100-200 nm. The filtration systems of the AWM and EDM processes were found to remove 70% and 90% the nanoparticles present, respectively. However, the particle concentration of the filtered water from the AWM was still four times higher than that found in regular tap water. These nanoparticles are mostly agglomerated, according to the microscopy analysis. Using the electron dispersive spectroscopy (EDS) technique, the particles are confirmed to come from the debris of the materials cut with the equipment. Since AWM and EDM are widely used, the handling and disposal of used filters collected with nanoparticles, release of nanoparticles to the sewer, and potential use of higher performance filters for these processes will deserve further consideration. PMID:24144041

  5. Electrical discharge machining in dentistry.

    PubMed

    Van Roekel, N B

    1992-01-01

    A brief history of electrical discharge machining (EDM) is given and the process is discussed. A description of the application of EDM for fabricating precision attachment removable partial dentures, fixed-removable implant prostheses, and titanium-ceramic crowns is presented. The advantages and disadvantages of the EDM process for the dental profession are evaluated. Although expensive, the procedure has merit. PMID:1524631

  6. Investigation of the effect of process parameters on the formation and characteristics of recast layer in wire-EDM of Inconel 718

    SciTech Connect

    Newton, Thomas R; Melkote, Shreyes N; Watkins, Thomas R; Trejo, Rosa M; Riester, Laura

    2009-01-01

    Inconel 718 is a high nickel content superalloy possessing high strength at elevated temperatures and resistance to oxidation and corrosion. The non-traditional manufacturing process of wire-electrical discharge machining (EDM) possesses many advantages over traditional machining during the manufacture of Inconel 718 parts. However, certain detrimental effects are also present and are due in large part to the formation of the recast layer. An experimental investigation was conducted to determine the main EDM parameters which contribute to recast layer formation in Inconel 718. It was found that average recast layer thickness increased primarily with energy per spark, peak discharge current, and current pulse duration. Over the range of parameters tested, the recast layer was observed to be between 5 and 9 {micro}m in average thickness, although highly variable in nature. The recast material was found to possess in-plane tensile residual stresses, as well as lower hardness and elastic modulus than the bulk material.

  7. Machine and process characterization

    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.

  8. Numerical prediction of heat affected layer in the EDM of aeronautical alloys

    NASA Astrophysics Data System (ADS)

    Izquierdo, B.; Plaza, S.; Sánchez, J. A.; Pombo, I.; Ortega, N.

    2012-10-01

    Electrical discharge machining is a popular non-traditional machining process, optimum for accurate machining of complex geometries in hard materials. EDM has been used for decades for machining pieces for the aeronautical industry, but surface integrity, and consequently the reliability of the machined parts have been questioned for long time due to the thermal nature of this machining process. In recent years, efforts have been put on modeling of the EDM process, being thermal modeling of the process one promising alternative. In a previous publication an original model of the EDM process was presented and it was used to predict material removal rate and surface finish for the EDM of steel. In the present article the capability of that modeling tool to characterize discharge properties and to predict recast layer distribution when EDMing an aeronautical alloy will be analyzed. EDM process of Inconel 718 has been studied and discharge properties have been obtained for four different EDM regimes. The capability of the model to reflect the behavior of more energetic regimes is discussed. Gathered information has been used to simulate the evolution of the recast layer generation process. Obtained results have been validated comparing them with experimental measurements, revealing a good correlation between predictions and experimental data. Finally, energetic efficiency of the discharge process has been simulated for the adjusted EDM regimes.

  9. Wire EDM for Refractory Materials

    NASA Technical Reports Server (NTRS)

    Zellars, G. R.; Harris, F. E.; Lowell, C. E.; Pollman, W. M.; Rys, V. J.; Wills, R. J.

    1982-01-01

    In an attempt to reduce fabrication time and costs, Wire Electrical Discharge Machine (Wire EDM) method was investigated as tool for fabricating matched blade roots and disk slots. Eight high-strength nickel-base superalloys were used. Computer-controlled Wire EDM technique provided high quality surfaces with excellent dimensional tolerances. Wire EDM method offers potential for substantial reductions in fabrication costs for "hard to machine" alloys and electrically conductive materials in specific high-precision applications.

  10. EDM and the resulting hydrogen embrittlement of maraging steel

    NASA Astrophysics Data System (ADS)

    Quick, Terrence M.

    1993-10-01

    The use of electrical discharge machining (EDM), or spark erosion as it is sometimes called, introduces hydrogen into maraging steel 250 such that brittle fracture surfaces result from embrittlement accelerated by slow-strain-rate tensile tests. Brittle fracture features indicate potential premature failure due to hydrogen embrittlement. Experimental control was provided by test specimens machined by abrasive waterjet, a machining technique that does not evolve hydrogen as a part of the machining process. Hydrogen concentration measurements indicate the hydrogen concentration of specimens fabricated by EDM is approximately 0.5 ppm, while that of specimens machined by abrasive waterjet is approximately 0.1 ppm. On the basis of constant-load tests, the time to failure of test specimens machined by EDM and loaded to 50% of the yield strength is estimated to be a minimum of 30 years.

  11. Ultrasonic Abrasive Removal Of EDM Recast

    NASA Technical Reports Server (NTRS)

    Mandel, Johnny L.; Jacobson, Marlowe S.

    1990-01-01

    Ultrasonic abrasive process removes layer of recast material generated during electrical-discharge machining (EDM) of damper pocket on turbine blade. Form-fitted tool vibrated ultrasonically in damper pocket from which material removed. Vibrations activate abrasive in pocket. Amount of material removed controlled precisely.

  12. Electrical-Discharge Machining Of Curved Passages

    NASA Technical Reports Server (NTRS)

    Guirguis, Kamal S.

    1993-01-01

    Electrical-discharge machining (EDM) used to cut deep hole with bends. EDM process done with articulating segmented electrode. Originally straight, electrode curved as it penetrates part, forming long, smoothly curving hole. After hole cut, honed with slurry to remove thin layer of recast metal created by EDM. Breakage of tools, hand deburring, and drilling debris eliminated.

  13. Effect of the Machining Processes on Low Cycle Fatigue Behavior of a Powder Metallurgy Disk

    NASA Technical Reports Server (NTRS)

    Telesman, J.; Kantzos, P.; Gabb, T. P.; Ghosn, L. J.

    2010-01-01

    A study has been performed to investigate the effect of various machining processes on fatigue life of configured low cycle fatigue specimens machined out of a NASA developed LSHR P/M nickel based disk alloy. Two types of configured specimen geometries were employed in the study. To evaluate a broach machining processes a double notch geometry was used with both notches machined using broach tooling. EDM machined notched specimens of the same configuration were tested for comparison purposes. Honing finishing process was evaluated by using a center hole specimen geometry. Comparison testing was again done using EDM machined specimens of the same geometry. The effect of these machining processes on the resulting surface roughness, residual stress distribution and microstructural damage were characterized and used in attempt to explain the low cycle fatigue results.

  14. Making EDM Electrodes By Stereolithography

    NASA Technical Reports Server (NTRS)

    Barlas, Philip A.

    1988-01-01

    Stereolithography is computer-aided manufacturing technique. Used to make models and molds of electrodes for electrical-discharge machining (EDM). Eliminates intermediate steps in fabrication of plastic model of object used in making EDM electrode to manufacture object or mold for object.

  15. Numerical study on the splitting of a vapor bubble in the ultrasonic assisted EDM process with the curved tool and workpiece.

    PubMed

    Shervani-Tabar, M T; Seyed-Sadjadi, M H; Shabgard, M R

    2013-01-01

    Electrical discharge machining (EDM) is a powerful and modern method of machining. In the EDM process, a vapor bubble is generated between the tool and the workpiece in the dielectric liquid due to an electrical discharge. In this process dynamic behavior of the vapor bubble affects machining process. Vibration of the tool surface affects bubble behavior and consequently affects material removal rate (MRR). In this paper, dynamic behavior of the vapor bubble in an ultrasonic assisted EDM process after the appearance of the necking phenomenon is investigated. It is noteworthy that necking phenomenon occurs when the bubble takes the shape of an hour-glass. After the appearance of the necking phenomenon, the vapor bubble splits into two parts and two liquid jets are developed on the boundaries of the upper and lower parts of the vapor bubble. The liquid jet developed on the upper part of the bubble impinges to the tool and the liquid jet developed on the lower part of the bubble impinges to the workpiece. These liquid jets cause evacuation of debris from the gap between the tool and the workpiece and also cause erosion of the workpiece and the tool. Curved tool and workpiece affect the shape and the velocity of the liquid jets during splitting of the vapor bubble. In this paper dynamics of the vapor bubble after its splitting near the curved tool and workpiece is investigated in three cases. In the first case surfaces of the tool and the workpiece are flat, in the second case surfaces of the tool and the workpiece are convex and in the third case surfaces of the tool and workpiece are concave. Numerical results show that in the third case, the velocity of liquid jets which are developed on the boundaries of the upper and lower parts of the vapor bubble after its splitting have the highest magnitude and their shape are broader than the other cases. PMID:22784706

  16. Experimental Study on Influence of Process Variables on Crater Dimensions in Micro- EDM of {gamma}-Titanium Aluminide

    SciTech Connect

    Mitra, S.; Paul, G.; Sarkar, S.; Nagahanumaiah

    2011-01-17

    In the present work the effect of different dielectric mediums in micro-EDM of {gamma}-Titanium Aluminide alloy have been investigated. Experiments were conducted both in the absence (dry conditions) and in presence of dielectric (EDM oil).Circular craters were produced both in the presence and absence of dielectric fluid using varying micro-EDM process variables i.e. open circuit voltage, discharge capacitance, pulse frequency and pulse-on-time. Over cut was measured from optical microscope images using Image Analyzer software. Influences of process variables and optimal conditions for minimum over cut on crater dimensions were investigated. ANOVA test which shows that capacitance of RC circuit contributes significantly in crater formation followed by pulse frequency. Optical photographs exhibit that over cut are less in air medium compared to oil medium.

  17. Bacillus subtilis EdmS (formerly PgsE) participates in the maintenance of episomes.

    PubMed

    Ashiuchi, Makoto; Yamashiro, Daisuke; Yamamoto, Kento

    2013-09-01

    Extrachromosomal DNA maintenance (EDM) is an important process in molecular breeding and for various applications in the construction of genetically engineered microbes. Here we describe a novel Bacillus subtilis gene involved in EDM function called edmS (formerly pgsE). Functional gene regions were identified using molecular genetics techniques. We found that EdmS is a membrane-associated protein that is crucial for EDM. We also determined that EdmS can change a plasmid vector with an unstable replicon and worse-than-random segregation into one with better-than-random segregation, suggesting that the protein functions in the declustering and/or partitioning of episomes. EdmS has two distinct domains: an N-terminal membrane-anchoring domain and a C-terminal assembly accelerator-like structure, and mutational analysis of edmS revealed that both domains are essential for EDM. Further studies using cells of Bacillus megaterium and itsedmS (formerly capE) gene implied that EdmS has potential as a molecular probe for exploring novel EDM systems. PMID:23583563

  18. Use of in-process EDM truing to generate complex contours on metal-bond, superabrasive grinding wheels for precision grinding structural ceramics

    SciTech Connect

    Piscotty, M. A., LLNL

    1997-08-01

    This paper presents recent work performed at Lawrence Livermore National Laboratory to develop cost-effective, versatile and robust manufacturing methods for grinding precision features in structural ceramics using metal-bond, superabrasive grinding wheels. The developed processes include utilizing specialized, on-machine hardware to generate precision profiles onto grinding wheels using electrical-discharge machining (EDM) and a contoured rotating electrode. The production grinding processes are described, which were developed and used to grind various precision details into a host of structural ceramics such as Al{sub 2}O{sub 3}, Si{sub 3}N{sub 4}, and BeO. The methodologies, hardware and results of both creep-feed and cylindrical grinding are described. A discussion of imparted grinding damage and wheel wear is also presented.

  19. Study of the Productivity and Surface Quality of Hybrid EDM

    NASA Astrophysics Data System (ADS)

    Wankhade, Sandeepkumar Haribhau; Sharma, Sunil Bansilal

    2016-01-01

    The development of new, advanced engineering materials and the need for precise prototypes and low-volume production have made the electric discharge machining (EDM), an important manufacturing process to meet such demands. It is capable of machining geometrically complex and hard material components, that are precise and difficult-to-machine such as heat treated tool steels, composites, super alloys, ceramics, carbides etc. Conversely the low MRR limits its productivity. Abrasive water jet machine (AJM) tools are quick to setup and offer quick turn-around on the machine and could make parts out of virtually any material. They do not heat the material hence no heat affected zone and can make any intricate shape easily. The main advantages are flexibility, low heat production and ability to machine hard and brittle materials. Main disadvantages comprise the process produces a tapered cut and health hazards due to dry abrasives. To overcome the limitations and exploit the best of each of above processes; an attempt has been made to hybridize the processes of AJM and EDM. The appropriate abrasives routed with compressed air through the hollow electrode to construct the hybrid process i.e., abrasive jet electric discharge machining (AJEDM), the high speed abrasives could impinge on the machined surface to remove the recast layer caused by EDM process. The main process parameters were varied to explore their effects and experimental results show that AJEDM enhances the machining efficiency with better surface finish hence can fit the requirements of modern manufacturing applications.

  20. Study of the machining process of nano-electrical discharge machining based on combined atomistic-continuum modeling method

    NASA Astrophysics Data System (ADS)

    Zhang, Guojun; Guo, Jianwen; Ming, Wuyi; Huang, Yu; Shao, Xinyu; Zhang, Zhen

    2014-01-01

    Nano-electrical discharge machining (nano-EDM) is an attractive measure to manufacture parts with nanoscale precision, however, due to the incompleteness of its theories, the development of more advanced nano-EDM technology is impeded. In this paper, a computational simulation model combining the molecular dynamics simulation model and the two-temperature model for single discharge process in nano-EDM is constructed to study the machining mechanism of nano-EDM from the thermal point of view. The melting process is analyzed. Before the heated material gets melted, thermal compressive stress higher than 3 GPa is induced. After the material gets melted, the compressive stress gets relieved. The cooling and solidifying processes are also analyzed. It is found that during the cooling process of the melted material, tensile stress higher than 3 GPa arises, which leads to the disintegration of material. The formation of the white layer is attributed to the homogeneous solidification, and additionally, the resultant residual stress is analyzed.

  1. Machining Performance and Surface Integrity of AISI D2 Die Steel Machined Using Electrical Discharge Surface Grinding Process

    NASA Astrophysics Data System (ADS)

    Choudhary, Rajesh; Kumar, Harmesh; Singh, Shankar

    2013-12-01

    The aim of this study is to establish optimum machining conditions for EDSG of AISI D2 die steel through an experimental investigation using Taguchi Methodology. To achieve combined grinding and electrical discharge machining, metal matrix composite electrodes (Cu-SiCp) were processed through powder metallurgy route. A rotary spindle attachment was developed to perform the EDSG experimental runs on EDM machine. Relationships were developed between various input parameters such as peak current, speed, pulse-on time, pulse-off time, abrasive particle size, and abrasive particle concentration, and output characteristics such as material removal rate and surface roughness. The optimized parameters were further validated by conducting confirmation experiments.

  2. Unsteady processes in machines.

    PubMed

    Pfeiffer, Friedrich

    1994-12-01

    Couplings in machines and mechanisms always have play and friction. While under loading, stick-slip phenomena and impact events can take place. Such processes are modeled as multibody systems whose structure is time variant or unsteady. The time-variant number of degrees of freedom is due to stick-slip contacts. The coupling characteristics become unsteady, for instance there exist jumps in the loads, if impacts occur. For establishing a uniform theory for such phenomena we use a Lagrangian approach connecting the additional constraint equations and the equations of motion by Lagrange multipliers, which are proportional to the constraint forces. Stick-slip and impact events are evaluated by indicator functions leading to special numerical algorithms for the search of switching points. Contact problems are formulated as a complementarity problem which can be solved by efficient algorithms. The theory is applied to rattling in gears, impact drilling machines, turbine blade dampers, and a woodpecker toy. In some of these applications, chaos as a result of bifurcations is possible, which results from variations in the parameters. (c) 1994 American Institute of Physics. PMID:12780146

  3. Experimental Investigations during Dry EDM of Inconel - 718

    NASA Astrophysics Data System (ADS)

    BHANDARE, A. S.; DABADE, U. A.

    2016-02-01

    Dry EDM is a modification of the conventional EDM process in which the liquid dielectric is replaced by a gaseous medium. Tubular tool electrodes are used and as the tool rotates, high velocity gas is supplied through it into the discharge gap. The flow of high velocity gas into the gap facilitates removal of debris and prevents excessive heating of the tool and work piece at the discharge spots. It is now known that apart from being an environment- friendly process, other advantages of the dry EDM process are low tool wear, lower discharge gap, lower residual stresses, smaller white layer and smaller heat affected zone. Keeping literature review into consideration, in this paper, an attempt has been made by selecting compressed air as a dielectric medium, with Inconel - 718 as a work piece material and copper as a tool electrode. Experiments are performed using Taguchi DoE orthogonal array to observe and analyze the effects of different process parameters to optimize the response variables such as material removal rate (MRR), surface roughness (Ra) and tool wear rate (TWR). In the current work, a unit has been developed to implement dry EDM process on existing oil based EDM machine.

  4. High-efficiency approach for fabricating MTE rotor by micro-EDM and micro-extrusion

    NASA Astrophysics Data System (ADS)

    Geng, Xuesong; Chi, Guanxin; Wang, Yukui; Wang, Zhenlong

    2014-07-01

    Micro-gas turbine engine (MTE) rotor is an important indicator of its property, therefore, the manufacturing technology of the microminiature rotor has become a hot area of research at home and abroad. At present, the main manufacturing technologies of the MTE rotor are directed forming fabrication technologies. However, these technologies have a series of problems, such as complex processing technology high manufacturing cost, and low processing efficiency, and so on. This paper takes advantage of micro electric discharge machining (micro-EDM) in the field of microminiature molds manufacturing, organizes many processing technologies of micro-EDM reasonably to improve processing accuracy, presents an integrated micro-EDM technology and its process flow to fabricate MTE rotor die, and conducts a series of experiments to verify efficiency of this integrated micro-EDM. The experiments results show that the MTE rotor die has sharp outline and ensure the good consistency of MTE rotor blades. Meanwhile, the MTE rotor die is applied to micro extrusion equipment, and technologies of micro-EDM and micro forming machining are combined based on the idea of the molds manufacturing, so the MTE rotor with higher aspect ratio and better consistency of blades can be manufactured efficiently. This research presents an integrated micro-EDM technology and its process flow, which promotes the practical process of MTE effectively.

  5. Corrosion Resistance Analysis of Sintered NdFeB Magnets Using Ultrasonic-Aided EDM Method

    NASA Astrophysics Data System (ADS)

    Li, L.; Wei, X. T.; Li, Z. Y.; Cheng, X.

    2015-01-01

    Sintered neodymium-iron-boron (NdFeB) permanent magnets are widely used in many fields because of their excellent magnetic property. However, their poor corrosion resistance has been cited as a potential problem that limits their extensive application. This paper presents an experimental investigation into the improvement of surface corrosion resistance with the ultrasonic-aided electrical discharge machining (U-EDM) method. A scanning electron microscope was used to analyze the surface morphology of recast layers formed through the EDM and U-EDM processes. The chemical structure and elements of these recast layers were characterized using x-ray diffraction and energy dispersive spectroscopy. Corrosion resistance was also studied by means of potentiodynamic polarization, electrochemical impedance spectroscopy, and immersion tests in 0.5 mol/L H2SO4 solution. Experimental results show that an amorphous structure was formed in the recast layer during the EDM and U-EDM processes and that this structure could improve the corrosion resistance of sintered NdFeB magnets. Moreover, the corrosion resistance of U-EDM-treated surface was better than that of the EDM-treated surface.

  6. Mathematical modeling and analysis of EDM process parameters based on Taguchi design of experiments

    NASA Astrophysics Data System (ADS)

    Laxman, J.; Raj, K. Guru

    2015-12-01

    Electro Discharge Machining is a process used for machining very hard metals, deep and complex shapes by metal erosion in all types of electro conductive materials. The metal is removed through the action of an electric discharge of short duration and high current density between the tool and the work piece. The eroded metal on the surface of both work piece and the tool is flushed away by the dielectric fluid. The objective of this work is to develop a mathematical model for an Electro Discharge Machining process which provides the necessary equations to predict the metal removal rate, electrode wear rate and surface roughness. Regression analysis is used to investigate the relationship between various process parameters. The input parameters are taken as peak current, pulse on time, pulse off time, tool lift time. and the Metal removal rate, electrode wear rate and surface roughness are as responses. Experiments are conducted on Titanium super alloy based on the Taguchi design of experiments i.e. L27 orthogonal experiments.

  7. Shaping of steel mold surface of lens array by electrical discharge machining with single rod electrode.

    PubMed

    Takino, Hideo; Hosaka, Takahiro

    2014-11-20

    We propose a method for fabricating a lens array mold by electrical discharge machining (EDM). In this method, the tips of rods are machined individually to form a specific surface, and then a number of the machined rods are arranged to construct an electrode for EDM. The repetition of the EDM process using the electrode enables a number of lens elements to be produced on the mold surface. The effectiveness of our proposed method is demonstrated by shaping a lens array mold made of stainless steel with 16 spherical elements, in which the EDM process with a single rod electrode is repeatedly conducted. PMID:25607880

  8. The Evolution of CERN EDMS

    NASA Astrophysics Data System (ADS)

    Wardzinska, Aleksandra; Petit, Stephan; Bray, Rachel; Delamare, Christophe; Garcia Arza, Griselda; Krastev, Tsvetelin; Pater, Krzysztof; Suwalska, Anna; Widegren, David

    2015-12-01

    Large-scale long-term projects such as the LHC require the ability to store, manage, organize and distribute large amounts of engineering information, covering a wide spectrum of fields. This information is a living material, evolving in time, following specific lifecycles. It has to reach the next generations of engineers so they understand how their predecessors designed, crafted, operated and maintained the most complex machines ever built. This is the role of CERN EDMS. The Engineering and Equipment Data Management Service has served the High Energy Physics Community for over 15 years. It is CERN's official PLM (Product Lifecycle Management), supporting engineering communities in their collaborations inside and outside the laboratory. EDMS is integrated with the CAD (Computer-aided Design) and CMMS (Computerized Maintenance Management) systems used at CERN providing tools for engineers who work in different domains and who are not PLM specialists. Over the years, human collaborations and machines grew in size and complexity. So did EDMS: it is currently home to more than 2 million files and documents, and has over 6 thousand active users. In April 2014 we released a new major version of EDMS, featuring a complete makeover of the web interface, improved responsiveness and enhanced functionality. Following the results of user surveys and building upon feedback received from key users group, we brought what we think is a system that is more attractive and makes it easy to perform complex tasks. In this paper we will describe the main functions and the architecture of EDMS. We will discuss the available integration options, which enable further evolution and automation of engineering data management. We will also present our plans for the future development of EDMS.

  9. Microelectrode array fabrication by electrical discharge machining and chemical etching.

    PubMed

    Fofonoff, Timothy A; Martel, Sylvain M; Hatsopoulos, Nicholas G; Donoghue, John P; Hunter, Ian W

    2004-06-01

    Wire electrical discharge machining (EDM), with a complementary chemical etching process, is explored and assessed as a method for developing microelectrode array assemblies for intracortically recording brain activity. Assembly processes based on these methods are highlighted, and results showing neural activity successfully recorded from the brain of a mouse using an EDM-based device are presented. Several structures relevant to the fabrication of microelectrode arrays are also offered in order to demonstrate the capabilities of EDM. PMID:15188855

  10. Improving Electrical Efficiency of Edm Power Supply

    NASA Astrophysics Data System (ADS)

    Toma, Emanoil; Simion, Carmen Mihaela

    2014-11-01

    This paper briefly presents the principal types of Pulse Generators for Electrical Discharge Machining and ways to improve electrical efficiency. A resonant converter with series-parallel LCC circuit, for EDM applications, was analyzed by PSpice simulation. The performances of EDM Power Supply were improved by adding an energy recovering - voltage limiter circuit. The shape of current pulse was changed by adding a supplementary MOSFET Switch in parallel with the gap. Two or more converters can be parallelized, in this way output current can be changed. A bloc-schema was conceived for EDM experimental set up

  11. Influence of Surface Position along the Working Range of Conoscopic Holography Sensors on Dimensional Verification of AISI 316 Wire EDM Machined Surfaces

    PubMed Central

    Fernández, Pedro; Blanco, David; Rico, Carlos; Valiño, Gonzalo; Mateos, Sabino

    2014-01-01

    Conoscopic holography (CH) is a non-contact interferometric technique used for surface digitization which presents several advantages over other optical techniques such as laser triangulation. Among others, the ability for the reconstruction of high-sloped surfaces stands out, and so does its lower dependence on surface optical properties. Nevertheless, similarly to other optical systems, adjustment of CH sensors requires an adequate selection of configuration parameters for ensuring a high quality surface digitizing. This should be done on a surface located as close as possible to the stand-off distance by tuning frequency (F) and power (P) until the quality indicators Signal-to-Noise Ratio (SNR) and signal envelope (Total) meet proper values. However, not all the points of an actual surface are located at the stand-off distance, but they could be located throughout the whole working range (WR). Thus, the quality of a digitized surface may not be uniform. The present work analyses how the quality of a reconstructed surface is affected by its relative position within the WR under different combinations of the parameters F and P. Experiments have been conducted on AISI 316 wire EDM machined flat surfaces. The number of high-quality points digitized as well as distance measurements between different surfaces throughout the WR allowed for comparing the metrological behaviour of the CH sensor with respect to a touch probe (TP) on a CMM. PMID:24662452

  12. Influence of surface position along the working range of conoscopic holography sensors on dimensional verification of AISI 316 wire EDM machined surfaces.

    PubMed

    Fernández, Pedro; Blanco, David; Rico, Carlos; Valiño, Gonzalo; Mateos, Sabino

    2014-01-01

    Conoscopic holography (CH) is a non-contact interferometric technique used for surface digitization which presents several advantages over other optical techniques such as laser triangulation. Among others, the ability for the reconstruction of high-sloped surfaces stands out, and so does its lower dependence on surface optical properties. Nevertheless, similarly to other optical systems, adjustment of CH sensors requires an adequate selection of configuration parameters for ensuring a high quality surface digitizing. This should be done on a surface located as close as possible to the stand-off distance by tuning frequency (F) and power (P) until the quality indicators Signal-to-Noise Ratio (SNR) and signal envelope (Total) meet proper values. However, not all the points of an actual surface are located at the stand-off distance, but they could be located throughout the whole working range (WR). Thus, the quality of a digitized surface may not be uniform. The present work analyses how the quality of a reconstructed surface is affected by its relative position within the WR under different combinations of the parameters F and P. Experiments have been conducted on AISI 316 wire EDM machined flat surfaces. The number of high-quality points digitized as well as distance measurements between different surfaces throughout the WR allowed for comparing the metrological behaviour of the CH sensor with respect to a touch probe (TP) on a CMM. PMID:24662452

  13. Extra-chromosomal DNA maintenance in Bacillus subtilis, dependence on flagellation factor FliF and moonlighting mediator EdmS.

    PubMed

    Hakumai, Yuichi; Shimomoto, Kouko; Ashiuchi, Makoto

    2015-05-15

    Extra-chromosomal DNA maintenance (EDM) as an important process in the propagation and genetic engineering of microbes. Bacillus subtilis EdmS (formerly PgsE), a protein comprising 55 amino acids, is a mediator of the EDM process. In this study, the effect of mutation of global regulators on B. subtilis EDM was examined. Mutation of the swrA gene abolished EdmS-mediated EDM. It is known that swrA predominantly regulates expression of the fla/che operon in B. subtilis. We therefore performed EDM analysis using fla/che-deletion mutants and identified an EDM-mediated EDM cooperator in the flgB-fliL region. Further genetic investigation identified the flagellation factor FliF is a crucial EDM cooperator. To our knowledge, this is the first observation of the moonlighting function of FliF in DNA maintenance. PMID:25843804

  14. A Comparative Study of Different Contour Machining Processes of UNS A92024-T3 Alloy

    NASA Astrophysics Data System (ADS)

    Batista, M.; Bienvenido, R.; Díaz, J. E.; Gómez, A.; Salguero, J.; Marcos, M.

    2009-11-01

    The optimisation of a manufacturing process involves, among other factors, the correct selection of the technologies for being applied in the process development. Nowadays, contour/profile milling is commonly used as a previous stage for pre-forming airship structural elements before being plastically deformed. Up to the time, contour milling processes is usually performed by High Speed Machining (HSM). However, currently, non traditional machining processes such as ElectroDischarge Machining (EDM) or Abrasive WaterJet Machining (AWJM) have been considered as alternative processes for being used in contouring of light aeronautical alloys. In this work, a basic study based on surface finish analysis has been developed for comparing the performance of different contouring processes applied on UNS A92024 Al-Cu alloy samples.

  15. Investigation of Wire Electrical Discharge Machining of Thin Cross-Sections and Compliant Mechanisms

    SciTech Connect

    Miller, Scott F.; Kao, Chen C.; Shih, Albert J.; Qu, Jun

    2005-01-01

    The wire electrical discharge machining (EDM) of cross-section with minimum thickness and compliant mechanisms is studied. Effects of EDM process parameters, particularly the spark cycle time and spark on-time on thin cross-section cutting of Nd-Fe-B magnetic material, carbon bipolar plate, and titanium are investigated. An envelope of feasible wire EDM process parameters is generated for the commercially pure titanium. The application of such envelope to select suitable EDM process parameters for micro feature generation is demonstrated. Scanning electron microscopy (SEM) analysis of EDM surface, subsurface, and debris are presented. SEM observations lead to a hypothesis based on the thermal and electrostatic stress induced fracture to explain the limiting factor for wire EDM cutting of thin-sections. Applications of the thin cross-section EDM cutting for manufacture of compliant mechanisms are discussed.

  16. 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.

  17. Development of a high precision tabletop versatile CNC wire-EDM for making intricate micro parts

    NASA Astrophysics Data System (ADS)

    Liao, Yunn-Shiuan; Chen, Shun-Tong; Lin, Chang-Sheng

    2005-02-01

    The micro-electrical discharge machining (micro-EDM) process has been proved to be appropriate for making 3D micro parts that are difficult and even impossible to manufacture by other processes. In this paper a high precision tabletop CNC wire electrical discharge machine (wire EDM) designed specifically for machining complex shape micro parts or structures is developed. In the machine developed, a novel micro-wire-cutting mechanism is designed, an approach to control wire tension by magnetic force is proposed and a servo feed control strategy, in accordance with the measured gap voltage, is designed and implemented. To verify the functions and capabilities of the machine developed, several thick micro outer and internal spur gears and rack are machined. It shows that the taper angle along the wall or cavity of a part that appears when other micro-EDM processes are applied can be avoided. A very good dimensional accuracy of 1 m and a surface finish of Rmax equal to 0.64 m are achieved. The satisfactory cutting of a miniature 3D pagoda with a micro-hooked structure also reveals that the machine developed is versatile, and can be used as a new tool for making intricate micro parts.

  18. Multi-Objective Optimization of Green EDM: An Integrated Theory

    NASA Astrophysics Data System (ADS)

    Jagadish; Ray, A.

    2015-01-01

    Electrical Discharge Machining (EDM) generates toxic substances, results in serious occupational health, and environmental issues, which influence the process parameters of EDM. These process parameters are multi-response parameters. The aim of this research is to solve the multi-response optimization problems and selection of optimum process parameters of green EDM using an integrated methodology comprising of entropy and Grey Relational Analysis (GRA). In this work, initially, an experiment was performed using Taguchi experimental technique. Thereafter, Entropy-GRA has been used to convert the multi-response parameters into single response parameter. Finally, the ranking of the parameter decides the best experimental set up and optimizes the input process parameters. In this work, Entropy method has been used to extract the precise value of each of the output parameters, which influences the gray relational grades for finding the optimal experimental set up. The justification of optimal input process parameters has been made using Analysis of Variance (ANOVA) analysis. An attempt has been made to compare the proposed methodology with the Fuzzy-TOPSIS and Taguchi-VIKOR methodology. The numerical result shows that the optimum process parameters are peak current (4.5 A), pulse duration (261 μs), dielectric level (80 mm) and flushing pressure (0.3 kg/cm2).

  19. High-speed micro-electro-discharge machining.

    SciTech Connect

    Chandrasekar, Srinivasan Dr. (.School of Industrial Engineering, West Lafayette, IN); Moylan, Shawn P. (School of Industrial Engineering, West Lafayette, IN); Benavides, Gilbert Lawrence

    2005-09-01

    When two electrodes are in close proximity in a dielectric liquid, application of a voltage pulse can produce a spark discharge between them, resulting in a small amount of material removal from both electrodes. Pulsed application of the voltage at discharge energies in the range of micro-Joules results in the continuous material removal process known as micro-electro-discharge machining (micro-EDM). Spark erosion by micro-EDM provides significant opportunities for producing small features and micro-components such as nozzle holes, slots, shafts and gears in virtually any conductive material. If the speed and precision of micro-EDM processes can be significantly enhanced, then they have the potential to be used for a wide variety of micro-machining applications including fabrication of microelectromechanical system (MEMS) components. Toward this end, a better understanding of the impacts the various machining parameters have on material removal has been established through a single discharge study of micro-EDM and a parametric study of small hole making by micro-EDM. The main avenues for improving the speed and efficiency of the micro-EDM process are in the areas of more controlled pulse generation in the power supply and more controlled positioning of the tool electrode during the machining process. Further investigation of the micro-EDM process in three dimensions leads to important design rules, specifically the smallest feature size attainable by the process.

  20. A novel power source for high-precision, highly efficient micro w-EDM

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong; Chen, Chi-Hung

    2015-07-01

    The study presents the development of a novel power source for high-precision, highly efficient machining of micropart microstructures using micro wire electrical discharge machining (w-EDM). A novel power source based on a pluri resistance-capacitance (pRC) circuit that can generate a high-frequency, high-peak current with a short pulse train is proposed and designed to enhance the performance of micro w-EDM processes. Switching between transistors is precisely controlled in the designed power source to create a high-frequency short-pulse train current. Various microslot cutting tests in both aluminum and copper alloys are conducted. Experimental results demonstrate that the pRC power source creates instant spark erosion resulting in markedly less material for removal, diminishing discharge crater size, and consequently an improved surface finish. A new evaluation approach for spark erosion ability (SEA) to assess the merits of micro EDM power sources is also proposed. In addition to increasing the speed of micro w-EDM by increasing wire feed rates by 1.6 times the original feed rate, the power source is more appropriate for machining micropart microstructures since there is less thermal breaking. Satisfactory cutting of an elaborate miniature hook-shaped structure and a high-aspect ratio microstructure with a squared-pillar array also reveal that the developed pRC power source is effective, and should be very useful in the manufacture of intricate microparts.

  1. Surface Integrity of Inconel 718 by Wire-EDM at Different Energy Modes

    NASA Astrophysics Data System (ADS)

    Li, L.; Wei, X. T.; Guo, Y. B.; Li, W.; Liu, J. F.

    2014-08-01

    Inconel alloys including IN 718 alloy are widely used in turbomachinery industry due to their superior mechanical properties. Inconel alloys are very difficult to machine using cutting and grinding. Wire electrical discharge machining (W-EDM) is an alternative process to manufacture complex Inconel parts. However, little research has been done on surface integrity by W-EDMed IN 718. This study focuses on surface integrity of IN 718 by W-EDM at different modes of discharge energy. The results show that the EDMed surface topography shows dominant coral reef microstructures at high energy mode, while random microvoids are dominant at low energy modes. The average roughness can be significantly reduced at low energy mode. A thick white layer is predominantly discontinuous and non-uniform at relative high energy modes. Microvoids are confined within the thick white layers and no microcracks were found in the subsurface. A thin white layer by trim cut at low energy mode becomes continuous, uniform, and is free of voids. Compared to the bulk, white layers have dramatic reduction in microhardness. In addition, surface alloying from wire electrode and water dielectric is obvious in main cut, but it can be minimized in trim cuts.

  2. Entering the operative correction machining processes CNC

    NASA Astrophysics Data System (ADS)

    Nekrasov, R. Yu; Starikov, A. I.; Lasukov, A. A.

    2015-09-01

    The article describes the solution to the problem of compensation of errors occurring during machining on CNC machines. We propose a method of mathematical modeling of processes diagnostics and control of technological equipment. The results of the diagnosis of the CNC machine, as well as the mathematical model describing the dependence of the positioning error of the executive bodies of operating component of cutting force PZ, in the range of movement OX.

  3. Machine Process Capability Information Through Six Sigma

    SciTech Connect

    Lackner, M.F.

    1998-03-13

    A project investigating details concerning machine process capability information and its accessibility has been conducted. The thesis of the project proposed designing a part (denoted as a machine capability workpiece) based on the major machining features of a given machine. Parts are machined and measured to gather representative production, short-term variation. The information is utilized to predict the expected defect rate, expressed in terms of a composite sigma level process capability index, for a production part. Presently, decisions concerning process planning, particularly what machine will statistically produce the minimum amount of defects based on machined features and associated tolerances, are rarely made. Six sigma tools and methodology were employed to conduct this investigation at AlliedSignal FM and T. Tools such as the thought process map, factor relationship diagrams, and components of variance were used. This study is progressing toward completion. This research study was an example of how machine process capability information may be gathered for milling planar faces (horizontal) and slot features. The planning method used to determine where and how to gather variation for the part to be designed is known as factor relationship diagramming. Components-of-variation is then applied to the gathered data to arrive at the contributing level of variation illustrated within the factor relationship diagram. The idea of using this capability information beyond process planning to the other business enterprise operations is proposed.

  4. Surface characteristics and damage of monocrystalline silicon induced by wire-EDM

    NASA Astrophysics Data System (ADS)

    Punturat, Jiraporn; Tangwarodomnukun, Viboon; Dumkum, Chaiya

    2014-11-01

    Wire-EDM has recently shown itself as an alternative approach for slicing silicon and other semiconductor materials without the presence of significant chipping as normally found in the traditional machining processes. However, the intensive electrical spark between a wire electrode and silicon can cause damage to the cut surface and subsurface in micro and nano-scale aspects. This paper presents the influence of major process parameters on the cut surface characteristics and damage in the wire-EDMing of silicon. An n-type monocrystalline silicon wafer was cut under different spark energy densities, duty cycles and dielectric flushing rates. Poor cut surface quality and high amount of electrode material deposition were obtained when low spark energy density, small duty cycle and low dielectric flushing rate were applied. Moreover, the amorphous and defective crystal structures of silicon were apparent under the low spark energy condition. The interactions between the wire-EDMing parameters and cut surface characteristics drawn in this study could have significances for the further development of EDM technology towards the fine-scale and damage-free processing of semiconductor materials.

  5. Dry Machining Process of Milling Machine using Axiomatic Green Methodology

    NASA Astrophysics Data System (ADS)

    Puspita Andriani, Gita; Akbar, Muhammad; Irianto, Dradjad

    2016-02-01

    Most of companies know that there are strategies to become green industry, and they realize that green efforts have impacts on product quality and cost. Axiomatic Green Methodology models the relationship between green, quality, and cost. This methodology starts with determining the green improvement objective and then continues with mapping the functional, economic, and green requirements. From the mapping, variables which affect the requirements are identified. Afterwards, the effect of each variable is determined by performing experiments and regression modelling. In this research, axiomatic green methodology was implemented to dry machining of milling machine in order to reduce the amount of coolant. Dry machining will be feasible if it is not worse than the minimum required quality. As a result, dry machining is feasible without producing any defect. The proposed machining parameter is to reduce the coolant flow rate from 6.882 ml/minute to 0 ml/minute, set the depth of cut at 1.2 mm, spindle rotation speed at 500 rpm, and feed rate at 128 mm/minute. This solution is also resulted in reduction of cost for 200.48 rupiahs for each process.

  6. A novel miniaturized EDM mechanism based on linear stepping ultrasonic motor

    NASA Astrophysics Data System (ADS)

    Tang, Y. J.; Hu, F. Q.; Wang, Z. L.; Zhao, W. S.

    2005-12-01

    In order to machine inclined micro-holes and operate in narrow space, a novel miniaturized EDM (Electro Discharge Machining) mechanism has been developed. Because of its merit of compact size (704050mm), the mechanism can be fixed on robot. The prototype of miniaturized EDM system consists of electrode direct drive unit, EDM electrical parameters and servo controller, ultrasonic EDM generator, manual robot, in addition to miniaturized EDM mechanism. Differential Reciprocating Driving Method (DRDM) is presented, and the coaxial forced vibration of electrode can be achieved. Coaxial vibration is applied to promote the evacuation of debris, and it helps to achieve stable and efficient machining. The optimal design of ultrasonic motor has been implemented using Finite Element Method (FEM), and the reasonable structure has been achieved. Feeding resolution of electrode can reach 40nm in differential reciprocating style. The holes with figures of ?85?m circle, ?90?m inclined circle, Y and inclined Y have been machined.

  7. Intelligent image processing for machine safety

    NASA Astrophysics Data System (ADS)

    Harvey, Dennis N.

    1994-10-01

    This paper describes the use of intelligent image processing as a machine guarding technology. One or more color, linear array cameras are positioned to view the critical region(s) around a machine tool or other piece of manufacturing equipment. The image data is processed to provide indicators of conditions dangerous to the equipment via color content, shape content, and motion content. The data from these analyses is then sent to a threat evaluator. The purpose of the evaluator is to determine if a potentially machine-damaging condition exists based on the analyses of color, shape, and motion, and on `knowledge' of the specific environment of the machine. The threat evaluator employs fuzzy logic as a means of dealing with uncertainty in the vision data.

  8. Performance and Surface Integrity of Ti6Al4V After Sinking EDM with Special Graphite Electrodes

    NASA Astrophysics Data System (ADS)

    Amorim, Fred L.; Stedile, Leandro J.; Torres, Ricardo D.; Soares, Paulo C.; Henning Laurindo, Carlos A.

    2014-04-01

    Titanium and its alloys have high chemical reactivity with most of the cutting tools. This makes it difficult to work with these alloys using conventional machining processes. Electrical discharge machining (EDM) emerges as an alternative technique to machining these materials. In this work, it is investigated the performance of three special grades of graphite as electrodes when ED-Machining Ti6Al4V samples under three different regimes. The main influences of electrical parameters are discussed for the samples material removal rate, volumetric relative wear and surface roughness. The samples surfaces were evaluated using SEM images, microhardness measurements, and x-ray diffraction. It was found that the best results for samples material removal rate, surface roughness, and volumetric relative wear were obtained for the graphite electrode with 10-μm particle size and negative polarity. For all samples machined by EDM and characterized by x-ray (XRD), it was identified the presence of titanium carbides. For the finish EDM regimes, the recast layer presents an increased amount of titanium carbides compared to semi-finish and rough regimes.

  9. Effect of hole geometry and Electric-Discharge Machining (EDM) on airflow rates through small diameter holes in turbine blade material

    NASA Technical Reports Server (NTRS)

    Hippensteele, S. A.; Cochran, R. P.

    1980-01-01

    The effects of two design parameters, electrode diameter and hole angle, and two machine parameters, electrode current and current-on time, on air flow rates through small-diameter (0.257 to 0.462 mm) electric-discharge-machined holes were measured. The holes were machined individually in rows of 14 each through 1.6 mm thick IN-100 strips. The data showed linear increase in air flow rate with increases in electrode cross sectional area and current-on time and little change with changes in hole angle and electrode current. The average flow-rate deviation (from the mean flow rate for a given row) decreased linearly with electrode diameter and increased with hole angle. Burn time and finished hole diameter were also measured.

  10. Intelligent image processing for machine operator safety

    NASA Astrophysics Data System (ADS)

    Harvey, Dennis N.

    1994-09-01

    This paper describes the use of intelligent image processing as a machine tool operator safety technology. One or more color, linear array cameras are positioned to view the critical region(s) around a machine tool. The image data is processed to provide indicators of an operator danger condition via color content, shape content, and motion content. The data from these analyses is then sent to a threat evaluator. The purpose of the evaluator is to determine if a danger condition exists based on the analyses of color, shape, and motion, and on `knowledge' of the specific environment of the machine tool. The threat evaluator employs fuzzy logic as a means of dealing with uncertainty in the vision data.

  11. The effect of microstructure on fatigue performance of Ti-6Al-4V alloy after EDM surface treatment for application in orthopaedics.

    PubMed

    Stráský, Josef; Janeček, Miloš; Harcuba, Petr; Bukovina, Michal; Wagner, Lothar

    2011-11-01

    Three different microstructures--equiaxed, bi-modal and coarse lamellar--are prepared from Ti-6Al-4V alloy. Electric discharge machining (EDM) with a high peak current (29 A) is performed in order to impose surface roughness and modify the chemical composition of the surface. Detailed scanning electron microscopy (SEM) investigation revealed a martensitic surface layer and subsurface heat affected zone (HAZ). EDX measurements showed carbon enriched remnants of the EDM process on the material surface. Rotating bending fatigue tests are undertaken for EDM processed samples for all three microstructures and also for electropolished-benchmark-samples. The fatigue performance is found to be rather poor and not particularly dependent on microstructure. The bi-modal microstructure shows a slightly superior high cycle fatigue performance. This performance can be further improved by a suitable heat treatment to an endurance limit of 200 MPa. PMID:22098894

  12. Electroformed Electrodes for Electrical-Discharge Machining

    NASA Technical Reports Server (NTRS)

    Werner, A.; Cassidenti, M.

    1984-01-01

    Copper electrodes replace graphite electrodes in many instances of electrical-discharge machining (EDM) of complex shapes. Copper electrodes wear longer and cause less contamination of EDM dielectric fluid than do graphite electrodes.

  13. Electrical discharge machining.

    PubMed

    LaBarge, K W

    1997-11-01

    This article describes a laboratory technique of achieving the highest degree of passive fit of an implant-retained restoration using electric discharge machining (EDM). This process can save time by eliminating the need for conventional soldering procedures, increase the longevity of the restoration, and when used along with the clinical technique of fabricating a verification index, eliminate the clinical try-in phase. PMID:9586551

  14. Process Waste Assessment Machine and Fabrication Shop

    SciTech Connect

    Phillips, N.M.

    1993-03-01

    This Process Waste Assessment was conducted to evaluate hazardous wastes generated in the Machine and Fabrication Shop at Sandia National Laboratories, Bonding 913, Room 119. Spent machine coolant is the major hazardous chemical waste generated in this facility. The volume of spent coolant generated is approximately 150 gallons/month. It is sent off-site to a recycler, but a reclaiming system for on-site use is being investigated. The Shop`s line management considers hazardous waste minimization very important. A number of steps have already been taken to minimize wastes, including replacement of a hazardous solvent with biodegradable, non-caustic solution and filtration unit; waste segregation; restriction of beryllium-copper alloy machining; and reduction of lead usage.

  15. Combining human and machine processes (CHAMP)

    NASA Astrophysics Data System (ADS)

    Sudit, Moises; Sudit, David; Hirsch, Michael

    2015-05-01

    Machine Reasoning and Intelligence is usually done in a vacuum, without consultation of the ultimate decision-maker. The late consideration of the human cognitive process causes some major problems in the use of automated systems to provide reliable and actionable information that users can trust and depend to make the best Course-of-Action (COA). On the other hand, if automated systems are created exclusively based on human cognition, then there is a danger of developing systems that don't push the barrier of technology and are mainly done for the comfort level of selected subject matter experts (SMEs). Our approach to combining human and machine processes (CHAMP) is based on the notion of developing optimal strategies for where, when, how, and which human intelligence should be injected within a machine reasoning and intelligence process. This combination is based on the criteria of improving the quality of the output of the automated process while maintaining the required computational efficiency for a COA to be actuated in timely fashion. This research addresses the following problem areas: • Providing consistency within a mission: Injection of human reasoning and intelligence within the reliability and temporal needs of a mission to attain situational awareness, impact assessment, and COA development. • Supporting the incorporation of data that is uncertain, incomplete, imprecise and contradictory (UIIC): Development of mathematical models to suggest the insertion of a cognitive process within a machine reasoning and intelligent system so as to minimize UIIC concerns. • Developing systems that include humans in the loop whose performance can be analyzed and understood to provide feedback to the sensors.

  16. Hadronic EDMs in SUSY GUTs

    SciTech Connect

    Kakizaki, Mitsuru

    2005-12-02

    We investigate the constraints from the null results of the hadronic electric dipole moment (EDM) searches on supersymmetric grand unified theories (SUSY GUTs). Especially we focus on (i) SUSY SU(5) GUTs with right-handed neutrinos and (ii) orbifold GUTs, where the GUT symmetry and SUSY are both broken by boundary conditions in the compactified extra dimensions. We demonstrate that the hadronic EDM experiments severely constrain SUSY GUT models. The interplay between future EDM and LFV experiments will probe the structures of the GUTs and the SUSY breaking mediation mechanism.

  17. Fabrication of high-density micro holes by upward batch micro EDM

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong

    2008-08-01

    A large number of micro holes are needed for biomedical parts, ink-jet nozzles and micro droplet spraying parts. In this study, an inexpensive machining approach for producing a batch of micro holes is proposed. A set of previously introduced w-EDM mechanisms is employed to horizontally cut the batch micro electrodes precisely. Through the process arrangement, the micro electrodes and workpiece are not unloaded, repositioned and re-corrected until all the tasks are completed. The micro workpiece is clamped onto the specially designed jig and moved above the micro electrodes to perform machining of the mass micro holes by upward batch micro EDM. The entire procedure is carried out on a developed multifunctional tabletop CNC machine tool. An array of 400 through holes of the identical sizes is successfully fabricated on a stainless-steel plate with a thickness of 30 µm by using the modified peck-drilling method. Experimental results confirmed that the proposed approach could accelerate the removal of debris, reduce the occurrence of abnormal discharges and decrease the machining time.

  18. Characterisation of integrated WAAM and machining processes

    NASA Astrophysics Data System (ADS)

    Adebayo, Adeyinka

    This research describes the process of manufacturing and machining of wire and arc additive manufactured (WAAM) thin wall structures on integrated and non-integrated WAAM systems. The overall aim of this thesis is to obtain a better understanding of deposition and machining of WAAM wall parts through an integrated system. This research includes the study of the comparison of deposition of WAAM wall structures on different WAAM platforms, namely an Integrated SAM Edgetek grinding machine, an ABB robot and a Friction Stir Welding (FSW) machine. The result shows that WAAM is a robustly transferable technique that can be implemented across a variety of different platforms typically available in industry.. For WAAM deposition, a rise in output repeatedly involves high welding travel speed that usually leads to an undesired humping effect. Part of the objectives of this work was to study the travel speed limit for humping. The findings from this research show that the travel speed limit falls within a certain region at which humping starts to occur. One of the objectives of this thesis was to study the effect of lubricants during sequential and non-sequential machining/deposition of the WAAM parts. Conventional fluid lubricants and solid lubricants were used. In addition, the effect of cleaning of deposited wall samples with acetone was also studied. A systematic study shows that a significant amount of solid lubricant contamination can be found in the deposited material. Furthermore, the results indicate that even cleaning of the wire and arc additive manufactured surfaces with acetone prior to the weld deposition can affect the microstructure of the deposited material..

  19. Numerical study on the hydrodynamic behavior of the dielectric fluid around an electrical discharge generated bubble in EDM

    NASA Astrophysics Data System (ADS)

    Shervani-Tabar, Mohammad T.; Mobadersany, Nima

    2013-09-01

    In the process of EDM, due to the electrical current, very small bubbles are created within the gap. These bubbles are connected to each other and generate a single bubble. The vapor bubble continues to grow until it finally collapses to small bubbles. The bubble behavior can be ascertained on the distribution of the pressure in the dielectric fluid around the bubble. In this paper, velocity fields and pressure distribution in the dielectric fluid around the bubble that is generated in the process of EDM are investigated numerically. The tool and the workpiece are assumed as two parallel rigid boundaries with dielectric liquid between them. The boundary integral equation method is applied for the numerical solution of the problem. This study can lead to better understanding of the bubble importance in the performance of the electrical discharge machining process.

  20. On the surface characteristics of a Zr-based bulk metallic glass processed by microelectrical discharge machining

    NASA Astrophysics Data System (ADS)

    Huang, Hu; Yan, Jiwang

    2015-11-01

    Microelectrical discharge machining (micro-EDM) performance of a Zr-based bulk metallic glass was investigated experimentally. Various discharge voltages and capacitances were used to study their effects on the material removal rate, cross-sectional profile, surface morphology and roughness, carbonization, and crystallization. Experimental results indicated that many randomly overlapped craters were formed on the EDMed surfaces, and their size and distribution were strongly dependent of the applied voltage and capacitance as well as their positions (center region or outer region), which further affected the surface roughness. Raman spectra and energy dispersive X-ray spectroscopy demonstrated that amorphous carbons originating from the decomposition of the EDM oil were deposited on the EDMed surface. Although some small sharp peaks appeared in the X-ray diffraction patterns of the micro-EDMed surfaces, a broad hump was maintained in all patterns, suggesting a dominant amorphous characteristic. Furthermore, crystallization was also affected by experimental conditions and machining positions. Results in this study indicate that micro-EDM under low discharge energy is useful for fabricating bulk metallic glass microstructures or components because of the ability to retain an amorphous structure.

  1. The study on the atomic force microscopy base nanoscale electrical discharge machining.

    PubMed

    Huang, Jen-Ching; Chen, Chung-Ming

    2012-01-01

    This study proposes an innovative atomic force microscopy (AFM) based nanoscale electrical discharge machining (AFM-based nanoEDM) system which combines an AFM with a self-produced metallic probe and a high-voltage generator to create an atmospheric environment AFM-based nanoEDM system and a deionized water (DI water) environment AFM-based nanoEDM system. This study combines wire-cut processing and electrochemical tip sharpening techniques on a 40-µm thick stainless steel sheet to produce a high conductive AFM probes, the production can withstand high voltage and large current. The tip radius of these probes is approximately 40 nm. A probe test was executed on the AFM using probes to obtain nanoscales morphology of Si wafer surface. The silicon wafer was as a specimen to carry out AFM-base nanoEDM process in atmospheric and DI water environments by AFM-based nanoEDM system. After experiments, the results show that the atmospheric and DI water environment AFM-based nanoEDM systems operate smoothly. From experimental results, it can be found that the electric discharge depth of the silicon wafer at atmospheric environments is a mere 14.54 nm. In a DI water environment, the depth of electric discharge of the silicon wafer can reach 25.4 nm. This indicates that the EDM ability of DI water environment AFM-based nanoEDM system is higher than that of atmospheric environment AFM-based nanoEDM system. After multiple nanoEDM process, the tips become blunt. After applying electrochemical tip sharpening techniques, the tip radius can return to approximately 40 nm. Therefore, AFM probes produced in this study can be reused. PMID:21898457

  2. Influence of electrical resistivity and machining parameters on electrical discharge machining performance of engineering ceramics.

    PubMed

    Ji, Renjie; Liu, Yonghong; Diao, Ruiqiang; Xu, Chenchen; Li, Xiaopeng; Cai, Baoping; Zhang, Yanzhen

    2014-01-01

    Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM) is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR), electrode wear ratio (EWR), and surface roughness (SR). The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 Ω·cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 Ω·cm is obviously different from that with the electrical resistivity lower than 687 Ω·cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical discharge machining ZnO/Al2O3 ceramic. PMID:25364912

  3. Influence of Electrical Resistivity and Machining Parameters on Electrical Discharge Machining Performance of Engineering Ceramics

    PubMed Central

    Ji, Renjie; Liu, Yonghong; Diao, Ruiqiang; Xu, Chenchen; Li, Xiaopeng; Cai, Baoping; Zhang, Yanzhen

    2014-01-01

    Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM) is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR), electrode wear ratio (EWR), and surface roughness (SR). The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 Ω·cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 Ω·cm is obviously different from that with the electrical resistivity lower than 687 Ω·cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical discharge machining ZnO/Al2O3 ceramic. PMID:25364912

  4. Micro Electro Discharge Machining of Electrically Nonconductive Ceramics

    SciTech Connect

    Schubert, A.; Zeidler, H.; Hackert, M.; Wolf, N.

    2011-05-04

    EDM is a known process for machining of hard and brittle materials. Due to its noncontact and nearly forceless behaviour, it has been introduced into micro manufacturing and through constant development it is now an important means for producing high-precision micro geometries. One restriction of EDM is its limitation to electrically conducting materials.Today many applications, especially in the biomedical field, make use of the benefits of ceramic materials, such as high strength, very low wear and biocompatibility. Common ceramic materials such as Zirconium dioxide are, due to their hardness in the sintered state, difficult to machine with conventional cutting techniques. A demand for the introduction of EDM to these materials could so far not be satisfied because of their nonconductive nature.At the Chemnitz University of Technology and the Fraunhofer IWU, investigations in the applicability of micro-EDM for the machining of nonconductive ceramics are being conducted. Tests are undertaken using micro-EDM drilling with Tungsten carbide tool electrodes and ZrO{sub 2} ceramic workpieces. A starting layer, in literature often referred to as 'assisting electrode' is used to set up a closed electric circuit to start the EDM process. Combining carbon hydride based dielectric and a specially designed low-frequency vibration setup to excite the workpiece, the process environment can be held within parameters to allow for a constant EDM process even after the starting layer is machined. In the experiments a cylindrical 120 {mu}m diameter Tungsten carbide tool electrode and Y{sub 2}O{sub 3}- and MgO- stabilized ZrO{sub 2} worpieces are used. The current and voltage signals of the discharges within the different stages of the process (machining of the starting layer, machining of the base material, transition stage) are recorded and their characteristics compared to discharges in metallic material. Additionally, the electrode feed is monitored. The influences of the process parameters are analysed with regard to the discharge type, electrode wear and process speed.Using the found parameters, micro geometries can be successfully machined into nonconductive Y{sub 2}O{sub 3}- and MgO- stabilized ZrO{sub 2} ceramic by means of micro-EDM.

  5. Micro Electro Discharge Machining of Electrically Nonconductive Ceramics

    NASA Astrophysics Data System (ADS)

    Schubert, A.; Zeidler, H.; Wolf, N.; Hackert, M.

    2011-05-01

    EDM is a known process for machining of hard and brittle materials. Due to its noncontact and nearly forceless behaviour, it has been introduced into micro manufacturing and through constant development it is now an important means for producing high-precision micro geometries. One restriction of EDM is its limitation to electrically conducting materials. Today many applications, especially in the biomedical field, make use of the benefits of ceramic materials, such as high strength, very low wear and biocompatibility. Common ceramic materials such as Zirconium dioxide are, due to their hardness in the sintered state, difficult to machine with conventional cutting techniques. A demand for the introduction of EDM to these materials could so far not be satisfied because of their nonconductive nature. At the Chemnitz University of Technology and the Fraunhofer IWU, investigations in the applicability of micro-EDM for the machining of nonconductive ceramics are being conducted. Tests are undertaken using micro-EDM drilling with Tungsten carbide tool electrodes and ZrO2 ceramic workpieces. A starting layer, in literature often referred to as `assisting electrode' is used to set up a closed electric circuit to start the EDM process. Combining carbon hydride based dielectric and a specially designed low-frequency vibration setup to excite the workpiece, the process environment can be held within parameters to allow for a constant EDM process even after the starting layer is machined. In the experiments a cylindrical 120 μm diameter Tungsten carbide tool electrode and Y2O3- and MgO- stabilized ZrO2 worpieces are used. The current and voltage signals of the discharges within the different stages of the process (machining of the starting layer, machining of the base material, transition stage) are recorded and their characteristics compared to discharges in metallic material. Additionally, the electrode feed is monitored. The influences of the process parameters are analysed with regard to the discharge type, electrode wear and process speed. Using the found parameters, micro geometries can be successfully machined into nonconductive Y2O3- and MgO- stabilized ZrO2 ceramic by means of micro-EDM.

  6. Electrical-Discharge Machining With Additional Axis

    NASA Technical Reports Server (NTRS)

    Malinzak, Roger M.; Booth, Gary N.

    1991-01-01

    Proposed electrical-discharge-machining (EDM) apparatus uses moveable vertical wire as electrode. Wire positionable horizontally along one axis as it slides vertically past workpiece. Workpiece indexed in rotation about horizontal axis. Because of symmetry of parts, process used to make two such parts at a time by defining boundary between them. Advantages: cost of material reduced, imparts less residual stress to workpiece, and less time spent machining each part when parts produced in such symmetrical pairs.

  7. Characterisation of TiC layers deposited using an electrical discharge coating process

    NASA Astrophysics Data System (ADS)

    Algodi, S. J.; Murray, J. W.; Clare, A. T.; Brown, P. D.

    2015-10-01

    Electrical discharge machining (EDM) is a non-conventional, high-accuracy machining process for the manufacture of complex shapes, regardless of hardness of the workpiece. There is interest to develop the EDM technique for coating or surface modification by using a powder metallurgy (PM) tool electrode and/or added powder suspended within the dielectric fluid. We report on the EDM deposition of TiC coatings onto stainless steel, using either Cu or TiC electrodes, with and without Ti powder in the working oil. EDM processed layers exhibited hardness values ∼ 3-4 times higher than the substrate, emphasising the ability of EDM to impart improved mechanical performance to the surface of austenitic stainless steel.

  8. Application of Taguchi technique coupled with grey relational analysis for multiple performance characteristics optimization of EDM parameters on ST 42 steel

    NASA Astrophysics Data System (ADS)

    Prayogo, Galang Sandy; Lusi, Nuraini

    2016-04-01

    The optimization technique of machining parameters considering multiple performance characteristics of non conventional machining EDM process using Taguchi method combined with grey relational analysis (GRA) is presented in this study. ST 42 steel was chosen as material work piece and graphite as electrode during this experiment. Performance characteristics such as material removal rate and overcut are selected to evaluated the effect of machining parameters. Current, pulse on time, pulse off time and discharging time/ Z down were selected as machining parameters. The experiments was conducted by varying that machining parameters in three different levels. Based on the Taguchi quality design concept, a L27 orthogonal array table was chosen for the experiments. By using the combination of GRA and Taguchi, the optimization of complicated multiple performance characteristics was transformed into the optimization of a single response performance index. Optimal levels of machining parameters were identified by using Grey Relational Analysis method. The statistical application of analysis of variance was used to determine the relatively significant machining parameters. The result of confirmation test indicted that the determined optimal combination of machining parameters effectively improve the performance characteristics of the machining EDM process on ST 42 steel.

  9. Flexible human machine interface for process diagnostics

    SciTech Connect

    Reifman, J.; Graham, G.E.; Wei, T.Y.C.; Brown, K.R.; Chin, R.Y.

    1996-05-01

    A flexible human machine interface to design and display graphical and textual process diagnostic information is presented. The system operates on different computer hardware platforms, including PCs under MS Windows and UNIX Workstations under X-Windows, in a client-server architecture. The interface system is customized for specific process applications in a graphical user interface development environment by overlaying the image of the process piping and instrumentation diagram with display objects that are highlighted in color during diagnostic display. Customization of the system is presented for Commonwealth Edison`s Braidwood PWR Chemical and Volume Control System with transients simulated by a full-scale operator-training simulator and diagnosed by a computer-based system.

  10. Process-based tolerance assessment of connecting rod machining process

    NASA Astrophysics Data System (ADS)

    Sharma, G. V. S. S.; Rao, P. Srinivasa; Surendra Babu, B.

    2016-01-01

    Process tolerancing based on the process capability studies is the optimistic and pragmatic approach of determining the manufacturing process tolerances. On adopting the define-measure-analyze-improve-control approach, the process potential capability index (C p) and the process performance capability index (C pk) values of identified process characteristics of connecting rod machining process are achieved to be greater than the industry benchmark of 1.33, i.e., four sigma level. The tolerance chain diagram methodology is applied to the connecting rod in order to verify the manufacturing process tolerances at various operations of the connecting rod manufacturing process. This paper bridges the gap between the existing dimensional tolerances obtained via tolerance charting and process capability studies of the connecting rod component. Finally, the process tolerancing comparison has been done by adopting a tolerance capability expert software.

  11. Wire-cut electrical discharge machinability of ceramics. Final report

    SciTech Connect

    Ricci, W.S.; Skeele, H.A.; Blumenthal, W.R.

    1987-09-01

    The wire-cut electrical discharge machinability of four ceramics was evaluated. Titanium diboride and silicon carbide workpieces were successfully cut in the monolithic state. Boron carbide could only be cut when a metallic sandwich structure was placed around the workpiece. Silicon nitride could not be successfully cut. Mechanisms of material removal as well as a minimum level of workpiece electrical conductance necessary for EDM are proposed. Characterization of the surface damage resulting from electrical-discharge machining is presented. Recast, partially melted, and heat-affected zones are identified. The effects of parametric processing variations on surface integrity are discussed. Flexure strength and residual stress data are compared for EDM cut and diamond-ground surfaces in titanium diboride. Certain limitations are proposed for the EDM fabrication of ceramic components where surface defects are strength limiting.

  12. Edme Mariotte and Newton's Cradle

    ERIC Educational Resources Information Center

    Cross, Rod

    2012-01-01

    The first recorded experiments describing the phenomena made popular by Newton's cradle appear to be those conducted by Edme Mariotte around 1670. He was quoted in Newton's "Principia," along with Wren, Wallis, and Huygens, as having conducted pioneering experiments on the collisions of pendulum balls. Each of these authors concluded that momentum…

  13. Simulation of Surface Integrity for Nanopowder-Mixed Dielectric in Micro Electrical Discharge Machining

    NASA Astrophysics Data System (ADS)

    Tan, P. C.; Yeo, S. H.

    2013-06-01

    The use of powder-mixed dielectric for electrical discharge machining (PMD-EDM) and micro-electrical discharge machining (PMD micro-EDM) has been shown to reduce machined surface roughness and surface defects, such as, recast layer thickness. However, these were mainly empirical studies which had limited capacity to elucidate the physics and characteristics of the PMD-EDM process. In the current study, a new numerical model has been developed to describe the PMD micro-EDM process. The model has taken into account the larger expansion of the plasma channel and reduction in heat flux distributed to the workpiece because of the presence of powder particles. It has been analyzed using finite element methods (FEMs) and based on the multiple discharge approach. The heat source expansion factor due to the presence of powder particles has been estimated to be 1.07 at 0.02 g/L powder concentration. The fraction of heat flux to the workpiece has been found to decrease from 0.24 at 0.02 g/L to 0.11 at 0.2 g/L powder concentration. For model validation, simulated R max and recast layer thickness values were compared with their corresponding measured values. The simulated and measured results varied with the same general trend which suggested that the proposed process model for PMD micro-EDM was fundamentally sound.

  14. EDM Electrode for Internal Grooves

    NASA Technical Reports Server (NTRS)

    Ramani, V.; Werner, A.

    1985-01-01

    Electroerosive process inexpensive alternative to broaching. Hollow brass electrodes, soldered at one end to stainless-steel holding ring, held in grooves in mandrel. These electrodes used to machine grooves electrically in stainless-steel tube three-eights inch (9.5 millimeters) in diameter. Tool used on tubes already in place in equipment.

  15. Effects of sandblasting and electrical discharge machining on porcelain adherence to cast and machined commercially pure titanium.

    PubMed

    Inan, Ozgür; Acar, Asli; Halkaci, Selçuk

    2006-08-01

    The aim of this study was to determine the effect of sandblasting and electrical discharge machining (EDM) on cast and machined titanium surfaces and titanium-porcelain adhesion. Twenty machined titanium specimens were prepared by manufacturer (groups 1 and 2). Thirty specimens were prepared with autopolymerizing acrylic resin. Twenty of these specimens (groups 3 and 4) were cast with commercially pure titanium and the alpha-case layer was removed. For control group (group 5), 10 specimens were cast by using NiCr alloy. Groups 2 and 4 were subjected to EDM while groups 1, 3, and 5 were subjected to sandblasting. Surface examinations were made by using a scanning electron microscope (SEM). A low-fusing porcelain was fused on the titanium surfaces, whereas NiCr specimens were covered using a conventional porcelain. Titanium-porcelain adhesion was characterized by a 3-point bending test. Results were analyzed by Kruskal-Wallis and Mann-Whitney U tests. Metal-porcelain interfaces were characterized by SEM. The bond strength of control group was higher than that of the titanium-porcelain system. There was no significant difference between cast and machined titanium groups (p > 0.05). There was no significant difference between EDM and sandblasting processes (p > 0.05). The use of EDM as surface treatment did not improve titanium-porcelain adhesion compared with sandblasting. PMID:16447164

  16. Simulation of Fatigue Crack Initiation at Corrosion Pits With EDM Notches

    NASA Technical Reports Server (NTRS)

    Smith, Stephen W.; Newman, John A.; Piascik, Robert S.

    2003-01-01

    Uniaxial fatigue tests were conducted to compare the fatigue life of laboratory produced corrosion pits, similar to those observed in the shuttle main landing gear wheel bolt-hole, and an electro-discharged-machined (EDM) flaw. EDM Jaws are used to simulate corrosion pits during shuttle wheel (dynamometer) testing. The aluminum alloy, (AA 7050) laboratory fatigue tests were conducted to simulate the local stress level contained in the wheel bolt-hole. Under this high local stress condition, the EDM notch produced a fatigue life similar to test specimens containing corrosion pits of similar size. Based on the laboratory fatigue test results, the EDM Jaw (semi-circular disc shaped) produces a local stress state similar to corrosion pits and can be used to simulate a corrosion pit during the shuttle wheel dynamometer tests.

  17. Feature Based Machining Process Planning V5.1

    Energy Science and Technology Software Center (ESTSC)

    2001-07-30

    The purpose of the FB-Machining Advisor product is to provide industry with an end user product that will enable end users to more effectively interact with a solid model for manufacturing applications. The product allows end users to visualize and organize their manufacturing process plans as they are being conceived; avoid redundant and time consuming geometric construction and calculation; automate geometric reasoning processes, and automate downstream manufacturing applications. The product augments a solid model representationmore » of the part with a set of machining features (e.g., pockets, steps, holes, cutouts). The product also enables end users to interact with a solid model to create process plans. It will automatically recognize, or interactively create and modify surface based machining features (represented by sets of faces on the solid model) and volumetric machining features which are represented by delta volumes (solid bodies representing volumes of material to be removed from the part). The FB-Machining Advisor will generate “in process shapes” that represent the shape of the work piece prior or subsequent to a material removal operation. It is designed to facilitate process change propagation in order to minimize rework resulting from process modifications. The machining features will provide vital shape and tolerance information (i.e. depth of pocket, minimum side radius of pocket, diameter of hole, maximum surface finish of side walls). The FB-Machining Advisor also integrates solid model based (3 Dimensional) tolerance information with the machining feature representations.« less

  18. Rapid prototyping of zirconium diboride/copper electrical discharge machining electrodes

    NASA Astrophysics Data System (ADS)

    Stucker, Brent Eric

    The acceptance of rapid prototyping (RP) as the predominant technique for producing polymer and paper parts directly from computer-aided design (CAD) models has led many corporations and universities to try to extend its capabilities to more robust materials. In addition to producing prototype metal and ceramic parts, a significant effort has been made to create parts that are useful as tools and dies or that reduce the time necessary to create tools and dies. Most materials used for tools and dies are very hard, because they need to be able to withstand millions of cycles before failing. Electrical discharge machining (EDM) is the most common method used to machine tools and dies out of hard materials. A method for producing EDM electrodes using RP could greatly reduce the time and cost involved in creating tools and dies. A new EDM electrode material made up of zirconium diboride and copper (ZrBsb2/Cu) that is superior to traditional EDM electrodes has been investigated. The processing techniques necessary for creating Zrsb2/Cu electrodes from powders of ZrB2 and copper have been developed. These ZrBsb2/Cu electrodes have a better wear ratio and a faster sink rate than graphite, copper or tungsten/copper EDM electrodes. Performance variables that were tracked are: (1) wear ratio, (2) sink rate and (3) surface finish, where ZrBsb2/Cu, copper, graphite and W/Cu were used as anodes (electrodes) and stainless steel as cathodes (workpieces). The ZrBsb2/Cu electrode material system retains its superior EDM electrode performance across a number of materials processing and compositional variations. Scanning electron microscopy (SEM) was used to study the electrodes after EDM. These SEM observations facilitated an understanding of the superior EDM electrode performance characteristics of ZrBsb2/Cu to traditional EDM electrode material systems. A method for creating geometrically-complex ZrBsb2/Cu EDM electrodes using the selective laser sintering (SLS) RP technique was developed. Polymer coated ZrBsb2 powders are processed in a SLS machine to produce the desired geometry. Subsequent polymer burnout, sintering of the ZrBsb2 and copper infiltration are performed in a high-temperature furnace.

  19. A Robust Helical Abrasive Flow Machining (HLX-AFM) Process

    NASA Astrophysics Data System (ADS)

    Brar, B. S.; Walia, R. S.; Singh, V. P.; Sharma, M.

    2013-01-01

    Abrasive flow machining (AFM) is a fine finishing process in which an abrasives laden semi-solid paste is used for finishing of internal inaccessible recesses or surfaces. Recently, several modifications in the tooling with/without additional machining action have been tried for increasing the material removal in the AFM. The present study is about a novel development in the AFM process, towards the enhancement of material removal rate while polishing the internal cylindrical surfaces. The modified process is termed as helical abrasive flow machining process (HLX-AFM). Taguchi's quality engineering approach has been applied to the developed HLX-AFM process, leading to the optimization of various process parameters and thus the development of a robust machining process with significantly enhanced material removal.

  20. Electric dipole moments (EDM) of ionic atoms

    NASA Astrophysics Data System (ADS)

    Oshima, Sachiko

    2010-03-01

    Recent investigations show that the second-order perturbation calculations of electric dipole moments (EDM) from the finite nuclear size as well as the relativistic effects are all canceled out by the third-order perturbation effects and that this is due to electron screening. To derive the nucleon EDM from the nucleus, we propose to measure the EDM of an ionic system. In this case, it is shown that the nucleon EDM can survive by the reduction factor of 1/Z for the ionic system with one electron stripped off.

  1. Electric dipole moments (EDM) of ionic atoms

    SciTech Connect

    Oshima, Sachiko

    2010-03-15

    Recent investigations show that the second-order perturbation calculations of electric dipole moments (EDM) from the finite nuclear size as well as the relativistic effects are all canceled out by the third-order perturbation effects and that this is due to electron screening. To derive the nucleon EDM from the nucleus, we propose to measure the EDM of an ionic system. In this case, it is shown that the nucleon EDM can survive by the reduction factor of 1/Z for the ionic system with one electron stripped off.

  2. Process for laser machining and surface treatment

    DOEpatents

    Neil, George R.; Shinn, Michelle D.

    2004-10-26

    An improved method and apparatus increasing the accuracy and reducing the time required to machine materials, surface treat materials, and allow better control of defects such as particulates in pulsed laser deposition. The speed and quality of machining is improved by combining an ultrashort pulsed laser at high average power with a continuous wave laser. The ultrashort pulsed laser provides an initial ultrashort pulse, on the order of several hundred femtoseconds, to stimulate an electron avalanche in the target material. Coincident with the ultrashort pulse or shortly after it, a pulse from a continuous wave laser is applied to the target. The micromachining method and apparatus creates an initial ultrashort laser pulse to ignite the ablation followed by a longer laser pulse to sustain and enlarge on the ablation effect launched in the initial pulse. The pulse pairs are repeated at a high pulse repetition frequency and as often as desired to produce the desired micromachining effect. The micromachining method enables a lower threshold for ablation, provides more deterministic damage, minimizes the heat affected zone, minimizes cracking or melting, and reduces the time involved to create the desired machining effect.

  3. State machine analysis of sensor data from dynamic processes

    DOEpatents

    Cook, William R.; Brabson, John M.; Deland, Sharon M.

    2003-12-23

    A state machine model analyzes sensor data from dynamic processes at a facility to identify the actual processes that were performed at the facility during a period of interest for the purpose of remote facility inspection. An inspector can further input the expected operations into the state machine model and compare the expected, or declared, processes to the actual processes to identify undeclared processes at the facility. The state machine analysis enables the generation of knowledge about the state of the facility at all levels, from location of physical objects to complex operational concepts. Therefore, the state machine method and apparatus may benefit any agency or business with sensored facilities that stores or manipulates expensive, dangerous, or controlled materials or information.

  4. An experimental study of electrochemical polishing for micro-electro-discharge-machined stainless-steel stents.

    PubMed

    Lappin, Derry; Mohammadi, Abdolreza Rashidi; Takahata, Kenichi

    2012-02-01

    This paper reports electrochemical polishing (EP) of 316L stainless-steel structures patterned using micro-electro-discharge machiningEDM) for application to stents including intelligent stents based on micro-electro-mechanical-systems technologies. For the process optimization, 10 μm deep cavities μEDMed on the planar material were polished in a phosphoric acid-based electrolyte with varying current densities and polishing times. The EP condition with a current density of 1.5 A/cm(2) for an EP time of 180 s exhibited the highest surface quality with an average roughness of 28 nm improved from~400 nm produced with high-energy μEDM. The EP of μEDMed surfaces was observed to produce almost constant smoothness regardless of the initial roughness determined by varying discharge energies. Energy-dispersive X-ray spectroscopy was performed on the μEDMed surfaces before and after EP. A custom rotational apparatus was used to polish tubular test samples including stent-like structures created using μEDM, demonstrating uniform removal of surface roughness and sharp edges from the structures. PMID:22183790

  5. The ACME Electron EDM Search

    NASA Astrophysics Data System (ADS)

    West, Adam; Demille, David; Lasner, Zack; O'Leary, Brendon; Baron, Jacob; Doyle, John; Gabrielse, Gerald; Hutzler, Nicholas; Panda, Cristian; Petrik, Elizabeth; ACME Collaboration

    2015-05-01

    We recently improved the limit on the electron electric dipole moment (eEDM), de, by an order of magnitude. An eEDM-induced energy shift consistent with zero implied a limit |de | < 9 . 6 ×10-29 e cm × (Eeff' /Eeff) (90 % c.l.). Eeff (Eeff') is the true (mean calculated = 78 GV/cm) value of the effective E -field acting on de. We are implementing various upgrades to substantially enhance usable molecule flux. These include a new type of buffer gas beam source based on a high-yield thermochemical reaction, coherent state preparation via STIRAP, and electrostatic focusing of the molecular beam. Preliminary tests demonstrated significant improvement in molecule number and we anticipate an overall factor of 100 increase. This would enable a tenfold improvement in statistical sensitivity, which would probe interactions at scales up to 10 TeV. Modifications are also being made to suppress the largest systematic errors associated with our previous result to reduce these below our projected statistical sensitivity. Supported by NSF and the Precision Measurement Grants Program of the National Institute of Standards and Technology.

  6. 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.

  7. nEDM at SNS

    SciTech Connect

    Clayton, Steven

    2014-07-30

    This PowerPoint presentation covered the following topics: Overview; participants in the collaboration; the experimental method and Free Precession Method descriptions; and then experimental design elements, ending with a summary. A new nEDM experiment is under development with a goal sensitivity 90% CL σd < (3-5) x 10-28 e-cm in 300 live-days; Free precession method: SQUIDS to read out the 3He precession frequency, Scintillation signal for the n relative precession frequency; Dressed spin method: Strong RF field to match n and 3He effective magnetic moments; Modulation/feedback of dressing parameter based on scintillation signal; and, Ongoing development/demonstration of many aspects of the apparatus (a subset was shown here).

  8. Hardware implementation of machine vision systems: image and video processing

    NASA Astrophysics Data System (ADS)

    Botella, Guillermo; García, Carlos; Meyer-Bäse, Uwe

    2013-12-01

    This contribution focuses on different topics covered by the special issue titled `Hardware Implementation of Machine vision Systems' including FPGAs, GPUS, embedded systems, multicore implementations for image analysis such as edge detection, segmentation, pattern recognition and object recognition/interpretation, image enhancement/restoration, image/video compression, image similarity and retrieval, satellite image processing, medical image processing, motion estimation, neuromorphic and bioinspired vision systems, video processing, image formation and physics based vision, 3D processing/coding, scene understanding, and multimedia.

  9. Innovative machine designs for radiation processing

    NASA Astrophysics Data System (ADS)

    Vroom, David

    2007-12-01

    In the 1990s Raychem Corporation established a program to investigate the commercialization of several promising applications involving the combined use of its core competencies in materials science, radiation chemistry and e-beam radiation technology. The applications investigated included those that would extend Raychem's well known heat recoverable polymer and wire and cable product lines as well as new potential applications such as remediation of contaminated aqueous streams. A central part of the program was the development of new accelerator technology designed to improve quality, lower processing costs and efficiently process conformable materials such at liquids. A major emphasis with this new irradiation technology was to look at the accelerator and product handling systems as one integrated, not as two complimentary systems.

  10. Review of "Conceptual Structures: Information Processing in Mind and Machine."

    ERIC Educational Resources Information Center

    Smoliar, Stephen W.

    This review of the book, "Conceptual Structures: Information Processing in Mind and Machine," by John F. Sowa, argues that anyone who plans to get involved with issues of knowledge representation should have at least a passing acquaintance with Sowa's conceptual graphs for a database interface. (Used to model the underlying semantics of a…

  11. Six-Axis Electrical-Discharge Machine

    NASA Technical Reports Server (NTRS)

    Werner, A. R.

    1983-01-01

    Electrical discharge machine (EDM) of unusual versitility made by conversion of radial drill. Drilling head is replaced by ram that holds and positions electrode. Tank and recirculation system for coolant are added. EDM has six independent motions and drastically reduced cost of manufacturing. New applications are constantly being found.

  12. A New Approach For FEM Simulation of NC Machining Processes

    NASA Astrophysics Data System (ADS)

    Wang, Sheng Ping; Padmanaban, Shivakumar

    2004-06-01

    The paper describes a new method for a finite element based pseudo-simulation of Numerically Controlled (NC) machining (material removal) processes. Industrial machining of a component usually results in warping or distortion due to the re-establishment of equilibrium in the retained part along with the relief of the insitu residual stresses in the removed part. In many cases, these distortions can be so large that the part may no longer be able to serve its designated functionality. Considering that the machining process is fundamentally a material removal process, a new method based on an automated removal of finite elements in the cutting area has been developed in the finite element analysis (FEA) software MSC.Marc to conduct pseudo-simulation of the NC machining process., A number of key software enhancements have been made to facilitate the pseudo-simulation of the NC machining process. First, a seamless interface has been developed to import APT/CL data generated by CAD/CAM systems. Then, the cutting paths have been generated based on information in the APT/CL files and used for the automatic detection of the intersection between the cutter and the finite element mesh. With each incremental motion of the cutter, the FEA solver detects all the elements that are located within the cutting path. Such elements are then deactivated in a step-by-step manner that is consistent with the actual machining process. In order to improve the fidelity of the cut area, local adaptive mesh refinement in the vicinity of the cutting tool is undertaken. This enables relatively coarser meshes away from the cut area and provides more accurate representation of the actual volume that is removed. As demonstrated by an industrial example, the enhanced software features in MSC.Marc have made it possible to practically and efficiently analyze complex machining processes of 3D production parts and provide an elegant tool for predicting distortions in large structures due to the relief of insitu residual stresses.

  13. MATERIAL PROCESSING FOR SELF-ASSEMBLING MACHINE SYSTEMS

    SciTech Connect

    K. LACKNER; D. BUTT; C. WENDT

    1999-06-01

    We are developing an important aspect of a new technology based on self-reproducing machine systems. Such systems could overcome resource limitations and control the deleterious side effects of human activities on the environment. Machine systems capable of building themselves promise an increase in industrial productivity as dramatic as that of the industrial revolution. To operate successfully, such systems must procure necessary raw materials from their surroundings. Therefore, next to automation, most critical for this new technology is the ability to extract important chemicals from readily available soils. In contrast to conventional metallurgical practice, these extraction processes cannot make substantial use of rare elements. We have designed a thermodynamically viable process and experimentally demonstrated most steps that differ from common practice. To this end we had to develop a small, disposable vacuum furnace system. Our work points to a viable extraction process.

  14. CNC electrical discharge machining centers

    SciTech Connect

    Jaggars, S.R.

    1991-10-01

    Computer numerical control (CNC) electrical discharge machining (EDM) centers were investigated to evaluate the application and cost effectiveness of establishing this capability at Allied-Signal Inc., Kansas City Division (KCD). In line with this investigation, metal samples were designed, prepared, and machined on an existing 15-year-old EDM machine and on two current technology CNC EDM machining centers at outside vendors. The results were recorded and evaluated. The study revealed that CNC EDM centers are a capability that should be established at KCD. From the information gained, a machine specification was written and a shop was purchased and installed in the Engineering Shop. The older machine was exchanged for a new model. Additional machines were installed in the Tool Design and Fabrication and Precision Microfinishing departments. The Engineering Shop machine will be principally used for the following purposes: producing deep cavities in small corner radii, machining simulated casting models, machining difficult-to-machine materials, and polishing difficult-to-hand polish mold cavities. 2 refs., 18 figs., 3 tabs.

  15. Cylindrical Wire Electrical Discharge Machining of Metal Bond Diamond Wheels- Part II: Wheel Wear Mechanism

    SciTech Connect

    McSpadden, SB

    2002-01-22

    The use of stereo scanning Electron Microscopy (SEM) to investigate the wear mechanism of the wire EDM true metal bond diamond wheel for ceramic grinding is presented. On the grinding wheel, a wedge-shape removal part was machined to enable the examination and measurement of the worn wheel surfaces using the stereo SEM. The stereo SEM was calibrated by comparing results of depth profile of a wear groove with the profilometer measurements. On the surface of the grinding wheel after wire EDM truing and before grinding, the diamond protruding heights were measured in the level of 35 {micro}m, comparing to the 54 {micro}m average size of the diamond in the grinding wheel. The gap between the EDM wire and rotating grinding wheel is estimated to be about 35 to 40 {micro}m. This observation indicates that, during the wire EDM, electrical sparks occur between the metal bond and EDM wire, which leaves the diamond protruding in the gap between the wire and wheel. The protruding diamond is immediately fractured at the start of the grinding process, even under a light grinding condition. After heavy grinding, the grinding wheel surface and the diamond protrusion heights are also investigated using the stereo SEM. The height of diamond protrusion was estimated in the 5 to 15 {micro}m range. This study has demonstrated the use of stereo SEM as a metrology tool to study the grinding wheel surface.

  16. Electrical-Discharge Machining Of Perpendicular Passages

    NASA Technical Reports Server (NTRS)

    Malinzak, R. Michael; Booth, Gary N.

    1996-01-01

    Perpendicular telescoping electrode used to perform electrical-discharge machining (EDM) of internal passage through previously inaccessible depth of metal workpiece. More specifically, used to make internal passage perpendicular to passage entering from outer surface.

  17. Contamination-Free Electrical-Discharge Machining

    NASA Technical Reports Server (NTRS)

    Schmidt, Mark G.

    1987-01-01

    Contamination of parts by electrical-discharge machining (EDM) almost completely eliminated by reversing flow of coolant. Flow reversed from usual direction so coolant carries contaminants out through passage in electrode. Coolant for reverse flow is pressurized dichlorodifluoromethane vapor.

  18. High resolution lithography-compatible micro-electro-discharge machining of bulk metal foils for micro-electro-mechanical systems

    NASA Astrophysics Data System (ADS)

    Richardson, Mark Thomas

    The application of batch mode micro-electro-discharge machining (microEDM) to the fabrication of micro-electro-mechanical systems has opened the door to lithographically compatible precision machining of all bulk metals. High volume applications in biomedical, communications, and consumer electronics devices are enabled by this technology. This dissertation explores the capabilities, limitations, and further improvement of high density batch mode microEDM. There are four parts to this effort described below. A machining resolution study of high density features in stainless steel identifies the design space. Lithographically fabricated copper tools with single cross, parallel line, and circle/square array features of 5--100microm width and 5--75microm spacing were used. The observed discharge gap varies with shape, spacing, and feature location from 3.8--8microm. As tool feature density is increased, debris accumulation effects begin to dominate, eventually degrading both tool and workpiece. Two new techniques for mitigating this debris build-up are separately investigated. The first is a silicon passivation coating which suppresses spurious discharges triggered from the sidewalls of the machining tool. By this method, for high density batch machining, mean tool wear rate decreases from a typical rate of about 34% to 1.7% and machining non-uniformity reduces from 4.9microm to 1.1microm across the workpiece. The second involves a two-step machining process that enhances the hydraulic removal of machining debris and therefore throughput. Wireless RF signals are inherently emitted by the micro-discharge process. This thesis describes the first reported wireless detection of debris accumulation during microEDM, enabling direct monitoring of machining quality in real time with 5dBm signal drop. The first wireless detection of the interface between two stacked metals during microEDM is also reported giving a 10dBm signal change. The technique enables direct monitoring of the discharge without the influence of terminal parasitics. Finally, the first study of the residual stress due to the recast layer left behind by microEDM is presented. The recast layer stress-thickness product ranged from 0.5--6 GPa-microm for discharge energies from 0.03--20microJ. The recast layer thickness ranges from 0.2--3.3microm. Low energy discharges allow precision microstructures to be fabricated from bulk metals. Application of microEDM technology to RF switches and stents is in the appendices.

  19. Characterization of electric discharge machining, subsequent etching and shot-peening as a surface treatment for orthopedic implants

    NASA Astrophysics Data System (ADS)

    Stráský, Josef; Havlíková, Jana; Bačáková, Lucie; Harcuba, Petr; Mhaede, Mansour; Janeček, Miloš

    2013-09-01

    Presented work aims at multi-method characterization of combined surface treatment of Ti-6Al-4V alloy for biomedical use. Surface treatment consists of consequent use of electric discharge machining (EDM), acid etching and shot peening. Surface layers are analyzed employing scanning electron microscopy and energy dispersive X-ray spectroscopy. Acid etching by strong Kroll's reagent is capable of removing surface layer of transformed material created by EDM. Acid etching also creates partly nanostructured surface and significantly contributes to the enhanced proliferation of the bone cells. The cell growth could be positively affected by the superimposed bone-inspired structure of the surface with the morphological features in macro-, micro- and nano-range. Shot peening significantly improves poor fatigue performance after EDM. Final fatigue performance is comparable to benchmark electropolished material without any adverse surface effect. The proposed three-step surface treatment is a low-cost process capable of producing material that is applicable in orthopedics.

  20. Open approach for machine diagnostics and process optimization

    NASA Astrophysics Data System (ADS)

    McLeod, C. Stuart; Thomas, David W.; West, Andrew A.; Armstrong, Neal A.

    1997-01-01

    Machine diagnostics and process optimization requires efficient techniques for the real time collection and dissemination of information to enterprise personnel. Open data presentations are required for the diverse software packages used by enterprise personnel, from process modeling and statistical process control to financial and Management Information Systems (MIS) packages. Current systems that enable rapid data collection tend to be vendor specific, point to point applications that are difficult and expensive to update, extend and modify. An open architecture is required that is capable of providing low cost real time collection and dissemination of information to end user applications. The development of an open architecture within the object oriented paradigm to solve a process optimization problem within a packaging organization is described in this paper. The architecture encompasses both the high level data dissemination and low level data storage and communications. A robust communications link between the sensors/intelligent nodes positioned on shop floor machines and the archive/dissemination medium is provided by a fieldbus network. The fieldbus communications link is configurable to allow the periodic sampling/monitoring shop floor data, and high performance collection of data regarding specific processes or events. The data transmission techniques utilized allow the high performance collection of data without disrupting object technology infrastructure. The common object request broker architecture is utilized to provide truly distributed systems for the myriad of applications used by enterprise personnel.

  1. Design and Implementation of Process Migrating among Multiple Virtual Machines

    NASA Astrophysics Data System (ADS)

    Shen, Si; Zhang, Zexian; Yang, Shuangxi; Guo, Ruilin; Jiang, Murong

    Process migrating technology usually is used to solve the problems like user process death, system crash or lower executing efficiency because of the load unbalancing among the multi-processors. Virtual machine can supply system level backup and migration. But it is too much overhead sometimes. In this paper, a process migration technology on program level is put forward and a demo program has been developed for validation. It possesses high performance, low cost and pertinence. Aiming at the information involved in process migration, obtain process data from JVM by calling Java JDI API, and transmit them to the node having idle computing resources. This technology is platform-independent, and the efficiency of distributed system would be enhanced with it. It also has the advantages such as strong commonality, protecting local environment from intrusion, and preventing from malicious code filching local information.

  2. Numerical study of the dielectric liquid around an electrical discharge generated vapor bubble in ultrasonic assisted EDM.

    PubMed

    Shervani-Tabar, Mohammad T; Mobadersany, Nima

    2013-07-01

    In electrical discharge machining due to the electrical current, very small bubbles are created in the dielectric fluid between the tool and the workpiece. Increase of the number of bubbles and their growth in size generate a single bubble. The bubble has an important role in electrical discharge machining. In this paper the effect of ultrasonic vibration of the tool and the velocity fields and pressure distribution in the dielectric fluid around the bubble in the process of electrical discharge machining are studied numerically. The boundary integral equation method is applied for the numerical solution of the problem. It is shown that ultrasonic vibration of the tool has great influence on the evolution of the bubble, fluid behavior and the efficiency of the machining in EDM. At the last stages of the collapse phase of the bubble, a liquid jet develops on the bubble which has different shapes. Due to the different cases, and a high pressure region appears just near the jet of the bubble. Also the fluid particles have the highest relative velocity just near the liquid jet of the bubble. PMID:23490015

  3. Process Monitoring Evaluation and Implementation for the Wood Abrasive Machining Process

    PubMed Central

    Saloni, Daniel E.; Lemaster, Richard L.; Jackson, Steven D.

    2010-01-01

    Wood processing industries have continuously developed and improved technologies and processes to transform wood to obtain better final product quality and thus increase profits. Abrasive machining is one of the most important of these processes and therefore merits special attention and study. The objective of this work was to evaluate and demonstrate a process monitoring system for use in the abrasive machining of wood and wood based products. The system developed increases the life of the belt by detecting (using process monitoring sensors) and removing (by cleaning) the abrasive loading during the machining process. This study focused on abrasive belt machining processes and included substantial background work, which provided a solid base for understanding the behavior of the abrasive, and the different ways that the abrasive machining process can be monitored. In addition, the background research showed that abrasive belts can effectively be cleaned by the appropriate cleaning technique. The process monitoring system developed included acoustic emission sensors which tended to be sensitive to belt wear, as well as platen vibration, but not loading, and optical sensors which were sensitive to abrasive loading. PMID:22163477

  4. Search for permanent EDM using laser cooled Fr atoms

    NASA Astrophysics Data System (ADS)

    Kawamura, Hirokazu; Aoki, T.; Arikawa, H.; Ezure, S.; Furukawa, T.; Harada, K.; Hatakeyama, A.; Hatanaka, K.; Hayamizu, T.; Imai, K.; Inoue, T.; Ishikawa, T.; Itoh, M.; Kato, T.; Murakami, T.; Nataraj, H. S.; Sato, T.; Shimizu, Y.; Wakasa, T.; Yoshida, H. P.; Sakemi, Y.

    2013-03-01

    The existence of a non-zero electric dipole moment (EDM) implies the violation of time reversal symmetry. As the time-reversal symmetry violation predicted by the Standard Model (SM) for the electron EDM is too small to be observed with current experimental techniques and any a non-zero EDM would indicate new physics beyond the SM. The tiny signal from the electron EDM is enhanced in the heavy atoms such as francium (Fr). We are constructing the laser-cooled Fr factory to search for the electron EDM.

  5. Machine processing of ERTS and ground truth data

    NASA Technical Reports Server (NTRS)

    Rogers, R. H. (Principal Investigator); Peacock, K.

    1973-01-01

    The author has identified the following significant results. Results achieved by ERTS-Atmospheric Experiment PR303, whose objective is to establish a radiometric calibration technique, are reported. This technique, which determines and removes solar and atmospheric parameters that degrade the radiometric fidelity of ERTS-1 data, transforms the ERTS-1 sensor radiance measurements to absolute target reflectance signatures. A radiant power measuring instrument and its use in determining atmospheric parameters needed for ground truth are discussed. The procedures used and results achieved in machine processing ERTS-1 computer -compatible tapes and atmospheric parameters to obtain target reflectance are reviewed.

  6. Statistical process control (SPC) for coordinate measurement machines

    SciTech Connect

    Escher, R.N.

    2000-01-04

    The application of process capability analysis, using designed experiments, and gage capability studies as they apply to coordinate measurement machine (CMM) uncertainty analysis and control will be demonstrated. The use of control standards in designed experiments, and the use of range charts and moving range charts to separate measurement error into it's discrete components will be discussed. The method used to monitor and analyze the components of repeatability and reproducibility will be presented with specific emphasis on how to use control charts to determine and monitor CMM performance and capability, and stay within your uncertainty assumptions.

  7. Automatic signal processing of front monitor radar for tunneling machines

    SciTech Connect

    Sato, Toru; Takeda, Kenya; Nagamatsu, Takashi; Wakayama, Toshio; Kimura, Iwane; Shinbo, Tetsuya

    1997-03-01

    It is planned to install a front monitoring impulse radar on the surface of the rotating drill of tunneling machines in order to detect obstacles such as casing pipes of vertical borings. The conventional aperture synthesis technique can no more be applied to such cases because the radar image of a pipe dies not constituent a hyperbola as is the case for linear scanning radars. The authors have developed a special purpose signal processing algorithm with the aid of the discrete model fitting method, which can be used for any pattern of scanning. The details of the algorithm are presented together with the results of numerical simulations and test site experiments.

  8. Experimental characterization of the inner surface in micro-drilling of spray holes: A comparison between ultrashort pulsed laser and EDM

    NASA Astrophysics Data System (ADS)

    Romoli, L.; Rashed, C. A. A.; Fiaschi, M.

    2014-03-01

    In this research, the inner surface characteristics of micro-drilled holes of fuel injector nozzles were analyzed by Shear Force Microscopy (SHFM). The surface texture was characterized by maximum peak-to-valley distance and periodicity whose dimensions were related to the adopted energy. 180 µm diameter holes were drilled using ultrashort pulsed laser process using pulse energies within the range of 10-50 µJ. Laser ablated surfaces in the tested energy range offer a smooth texture with a peculiar periodic structure with a variation in height between 60 and 90 nm and almost constant periodicity. The Scanning Electron Microscopy (SEM) photograph of the Laser Induced Periodic Surface Structure (LIPSS) showed the co-existence of Low Spatial Frequency LIPSS (LSFL) and High Spatial Frequency LIPSS (HSFL). A comparative analysis was carried out between the highest laser pulse energy in the tested range energy laser drilling which enables the shortest machining time and micro-Electrical Discharge Machining (µ-EDM). On the contrary, results showed that surfaces obtained by electro-erosion are characterized by a random distribution of craters with a total excursion up to 1.5 µm with a periodicity of 10 µm. The mean-squared surface roughness (Rq) derived from the scanned maps ranges between 220 and 560 nm for µ-EDM, and between 50 and 100 nm for fs-pulses laser drilling.

  9. Parallel astronomical data processing with Python: Recipes for multicore machines

    NASA Astrophysics Data System (ADS)

    Singh, Navtej; Browne, Lisa-Marie; Butler, Ray

    2013-08-01

    High performance computing has been used in various fields of astrophysical research. But most of it is implemented on massively parallel systems (supercomputers) or graphical processing unit clusters. With the advent of multicore processors in the last decade, many serial software codes have been re-implemented in parallel mode to utilize the full potential of these processors. In this paper, we propose parallel processing recipes for multicore machines for astronomical data processing. The target audience is astronomers who use Python as their preferred scripting language and who may be using PyRAF/IRAF for data processing. Three problems of varied complexity were benchmarked on three different types of multicore processors to demonstrate the benefits, in terms of execution time, of parallelizing data processing tasks. The native multiprocessing module available in Python makes it a relatively trivial task to implement the parallel code. We have also compared the three multiprocessing approaches-Pool/Map, Process/Queue and Parallel Python. Our test codes are freely available and can be downloaded from our website.

  10. A Study on the Optimization Performance of Fireworks and Cuckoo Search Algorithms in Laser Machining Processes

    NASA Astrophysics Data System (ADS)

    Goswami, D.; Chakraborty, S.

    2014-11-01

    Laser machining is a promising non-contact process for effective machining of difficult-to-process advanced engineering materials. Increasing interest in the use of lasers for various machining operations can be attributed to its several unique advantages, like high productivity, non-contact processing, elimination of finishing operations, adaptability to automation, reduced processing cost, improved product quality, greater material utilization, minimum heat-affected zone and green manufacturing. To achieve the best desired machining performance and high quality characteristics of the machined components, it is extremely important to determine the optimal values of the laser machining process parameters. In this paper, fireworks algorithm and cuckoo search (CS) algorithm are applied for single as well as multi-response optimization of two laser machining processes. It is observed that although almost similar solutions are obtained for both these algorithms, CS algorithm outperforms fireworks algorithm with respect to average computation time, convergence rate and performance consistency.

  11. Electric-Discharge Machining Techniques for Evaluating Tritium Effects on Materials

    SciTech Connect

    Morgan, M.J.

    2003-11-07

    In this investigation, new ways to evaluate the long-term effects of tritium on the structural properties of components were developed. Electric-discharge machining (EDM) techniques for cutting tensile and fracture toughness samples from tritium exposed regions of returned reservoirs were demonstrated. An existing electric discharge machine was used to cut sub-size tensile and fracture toughness samples from the inside surfaces of reservoir mockups. Tensile properties from the EDM tensile samples were similar to those measured using full-size samples cut from similar stock. Although the existing equipment could not be used for machining tritium-exposed hardware, off-the shelf EDM units are available that could. With the right equipment and the required radiological controls in place, similar machining and testing techniques could be used to directly measure the effects of tritium on the properties of material cut from reservoir returns. Stress-strain properties from tritium-exposed reservoirs would improve finite element modeling of reservoir performance because the data would be representative of the true state of the reservoir material in the field. Tensile data from samples cut directly from reservoirs would also complement existing shelf storage and burst test data of the Life Storage Program and help answer questions about a specific reservoir's processing history and properties.

  12. Electrical Discharge Machining Techniques for Evaluating the Effects of Tritium on Materials

    SciTech Connect

    IMRICH, KENNETH

    2004-03-24

    In this investigation, new ways to evaluate the long-term effects of tritium on the structural properties of components were developed. Electric discharge machining (EDM) techniques for cutting tensile and fracture toughness samples from the tritium-exposed regions of returned reservoirs were demonstrated. An existing electric discharge machine was used to cut sub-size tensile and fracture toughness samples from the inside walls of reservoir mock-ups. Tensile properties from the EDM tensile samples were similar to those measured using full-size samples cut from similar stock. Although the existing equipment could not be used for machining tritium-exposed hardware, off-the-shelf EDM units are available that could. With the right equipment and the required radiological controls in place, similar machining and testing techniques could be used to directly measure the effects of tritium on the properties of material cut from reservoir returns. Stress-strain property data from tritium-exposed reservoirs would improve finite-element modeling of reservoir performance because the data are representative of the true state of the reservoir material in the field. Tensile data from samples cut directly from reservoirs complement existing shelf storage and burst test data of the Life Storage Program and help answer questions about a specific reservoir's processing history and properties.

  13. Search for electron EDM with laser cooled radioactive atom

    NASA Astrophysics Data System (ADS)

    Inoue, T.; Arikawa, H.; Ezure, S.; Harada, K.; Hayamizu, T.; Ishikawa, T.; Itoh, M.; Kato, T.; Kawamura, H.; Nataraj, H. S.; Sato, T.; Aoki, T.; Furukawa, T.; Hatakeyama, A.; Hatanaka, K.; Imai, K.; Murakami, T.; Shimizu, Y.; Wakasa, T.; Yoshida, H. P.; Sakemi, Y.

    2013-05-01

    The permanent electric dipole moment (EDM) of the elementary particle has the sensitivity to the CP violation in the theories beyond the standard model (SM). The search for the EDM constitutes the stringent test to discriminate between the SM and beyond it. We plan to perform the electron EDM search by using the laser cooled francium (Fr) atom which has the largest enhancement factor of the electron EDM in the alkali atoms. In this paper, the present status of the laser cooled Fr factory that is being constructed at Cyclotron and Radioisotope Center (CYRIC), Tohoku University are reported.

  14. CryoEDM: A cryogenic experiment to measure the neutron electric dipole moment

    NASA Astrophysics Data System (ADS)

    van der Grinten, M. G. D.; CryoEDM Collaboration; Balashov, S. N.; Francis, V.; Green, K.; Iaydjiev, P. S.; Ivanov, S. N.; Khazov, A.; Tucker, M. A. H.; Wark, D. L.; Davidson, A.; Hardiman, M.; Harris, P. G.; Katsika, K.; Pendlebury, J. M.; Peeters, S. J. M.; Shiers, D. B.; Smith, P.; Townsley, C.; Wardell, I.; Clarke, C.; Henry, S.; Kraus, H.; McCann, M.; Geltenbort, P.; Yoshiki, Y.

    2009-12-01

    CryoEDM is an experiment that aims to measure the electric dipole moment (EDM) of the neutron to a precision of 10 -28 e cm. A description of CryoEDM, the apparatus, technologies and commissioning is presented.

  15. Information integration and diagnosis analysis of equipment status and production quality for machining process

    NASA Astrophysics Data System (ADS)

    Zan, Tao; Wang, Min; Hu, Jianzhong

    2010-12-01

    Machining status monitoring technique by multi-sensors can acquire and analyze the machining process information to implement abnormity diagnosis and fault warning. Statistical quality control technique is normally used to distinguish abnormal fluctuations from normal fluctuations through statistical method. In this paper by comparing the advantages and disadvantages of the two methods, the necessity and feasibility of integration and fusion is introduced. Then an approach that integrates multi-sensors status monitoring and statistical process control based on artificial intelligent technique, internet technique and database technique is brought forward. Based on virtual instrument technique the author developed the machining quality assurance system - MoniSysOnline, which has been used to monitoring the grinding machining process. By analyzing the quality data and AE signal information of wheel dressing process the reason of machining quality fluctuation has been obtained. The experiment result indicates that the approach is suitable for the status monitoring and analyzing of machining process.

  16. Electrical discharge machining: occupational hygienic characterization using emission-based monitoring.

    PubMed

    Evertz, Sven; Dott, Wolfgang; Eisentraeger, Adolf

    2006-09-01

    Hazardous potential in industrial environments is normally assessed by means of immission-based sampling and analyses. This approach is not adequate, if effects of specific technical adjustments at machine tools or working processes on hygienic parameters should be assessed. This work has focused on the optimization of a manufacturing process (electrical discharge machining, EDM), with regard to risk reduction assessment. It is based on emission analyses rather than immision analyses. Several technical EDM parameters have been examined for their influence on air-based emissions. Worktools and workpieces used have a strong influence on aliphatic compounds and metals but not on volatile organic compounds (benzene, toluene, ethylene-benzene and xylene (BTEX)) and polycyclic aromatic hydrocarbons (PAHs) in air emissions. Increasing the dielectric (mineral oil) level above processing location decreases BTEX, chromium, nickel and PAH emissions. Aliphatic compounds, in contrast, increase in air emissions. EDM current used has a positive relationship with all substances analyzed in air emissions. Indicative immission concentrations, as can be expected under EDM conditions, are estimated in a predictive scenario. The results of this characterization give rise to an important conclusion in that risk assessment so far has been using incorrect parameters: total aliphatic compounds. Maximum level of chromium is reached long before limit values of aliphatic compounds are exceeded. Because of the fact that metals, like chromium, also have a higher hazardous potential, metal analysis should be introduced in future risk assessment. This experimental approach, that captures total emission of the electrical discharge machine, and is not solely based on immission values, has lead to a better understanding of the production process. This information is used to extract recommendations regarding monitoring aspects and protection measures. PMID:16781192

  17. Efficient dielectric fluid approach in electrodischarge finish machining on the material surface roughness of titanium alloy Ti-621/0.8

    NASA Astrophysics Data System (ADS)

    Mihai, N. V.; Brabie, G.

    2015-11-01

    This study was developed to reveal the correlation between current intensity and pulse off time with surface roughness of Ti-621/0.8 in fine EDM machining, in a unique manner of dielectric fluid approach. Depth of cut was taken in consideration to be not as high 1 gm due to the fact that good results were taken for more less heights before. In the case of Ti alloy (Ti-621/0.8) bar, EDM machining with low parameters (limited 110 V) is a delicate process, in which reaching SR under 1 gm is a challenge. Cooper and Graphite electrodes were used, die sinker oil dielectric from machine manufacture was used, without thermal modification to workpiece or electrode, just active dielectric compensatory fluid pumping solution with 0.5 MPa.

  18. Shared and service-oriented CNC machining system for intelligent manufacturing process

    NASA Astrophysics Data System (ADS)

    Li, Yao; Liu, Qiang; Tong, Ronglei; Cui, Xiaohong

    2015-11-01

    To improve efficiency, reduce cost, ensure quality effectively, researchers on CNC machining have focused on virtual machine tool, cloud manufacturing, wireless manufacturing. However, low level of information shared among different systems is a common disadvantage. In this paper, a machining database with data evaluation module is set up to ensure integrity and update. An online monitoring system based on internet of things and multi-sensors "feel" a variety of signal features to "percept" the state in CNC machining process. A high efficiency and green machining parameters optimization system "execute" service-oriented manufacturing, intelligent manufacturing and green manufacturing. The intelligent CNC machining system is applied in production. CNC machining database effectively shares and manages process data among different systems. The prediction accuracy of online monitoring system is up to 98.8% by acquiring acceleration and noise in real time. High efficiency and green machining parameters optimization system optimizes the original processing parameters, and the calculation indicates that optimized processing parameters not only improve production efficiency, but also reduce carbon emissions. The application proves that the shared and service-oriented CNC machining system is reliable and effective. This research presents a shared and service-oriented CNC machining system for intelligent manufacturing process.

  19. Preset Electrodes for Electrical-Discharge Machining

    NASA Technical Reports Server (NTRS)

    Coker, Bill E.

    1987-01-01

    New electrode holder for electrical-discharge machining (EDM) provides for repeatable loading and setting of many electrodes. New holder is rotating-index tool carrying six, eight, or more electrodes. Before use, all electrodes set with aid of ring surrounding tool, and locked in position with screws. When electrode replaced, EDM operator pulls spring-loaded pin on tool so it rotates about center pin. Fresh electrode then rotated into position against workpiece.

  20. Flotation machine and process for removing impurities from coals

    DOEpatents

    Szymocha, K.; Ignasiak, B.; Pawlak, W.; Kulik, C.; Lebowitz, H.E.

    1995-12-05

    The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other mineral particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal. 4 figs.

  1. Flotation machine and process for removing impurities from coals

    DOEpatents

    Szymocha, K.; Ignasiak, B.; Pawlak, W.; Kulik, C.; Lebowitz, H.E.

    1997-02-11

    The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other minerals particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal. 4 figs.

  2. Flotation machine and process for removing impurities from coals

    DOEpatents

    Szymocha, Kazimierz; Ignasiak, Boleslaw; Pawlak, Wanda; Kulik, Conrad; Lebowitz, Howard E.

    1997-01-01

    The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other minerals particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal.

  3. Flotation machine and process for removing impurities from coals

    DOEpatents

    Szymocha, Kazimierz; Ignasiak, Boleslaw; Pawlak, Wanda; Kulik, Conrad; Lebowitz, Howard E.

    1995-01-01

    The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other minerals particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal.

  4. Enhanced osteoblast response to electrical discharge machining surface.

    PubMed

    Otsuka, Fukunaga; Kataoka, Yu; Miyazaki, Takashi

    2012-01-01

    The purpose of this study is to investigate the surface characteristics and biocompatibility of titanium (Ti) surfaces modified by wire electrical discharge machining (EDM). EDM surface characteristics were evaluated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thin-film X-ray diffractometry (XRD) and contact angle measurements. MC3T3-E1 cell morphology, attachment and proliferation, as well as analysis of osteoblastic gene expressions, on machined surfaces and EDM surfaces were also evaluated. EDM surfaces exhibited high super hydrophilicity, due to high surface energy. XPS and XRD revealed that a passive oxide layer with certain developing thickness onto. EDM surfaces promoted cell attachment, but restrained proliferation. Counted cell numbers increased significantly on the machined surfaces as compared to the EDM surfaces. Real-time PCR analyses showed significantly higher relative mRNA expression levels of osteoblastic genes (ALP, osteocalcin, Runx2, Osterix) in cells cultured on the EDM surfaces as compared to cells cultured on the machined surfaces. PMID:22447066

  5. MEASUREMENT OF INDOOR AIR EMISSIONS FROM DRY-PROCESS PHOTOCOPY MACHINES

    EPA Science Inventory

    The article provides background information on indoor air emissions from office equipment, with emphasis on dry-process photocopy machines. The test method is described in detail along with results of a study to evaluate the test method using four dry-process photocopy machines. ...

  6. Effect of Powder-Suspended Dielectric on the EDM Characteristics of Inconel 625

    NASA Astrophysics Data System (ADS)

    Talla, Gangadharudu; Gangopadhyay, S.; Biswas, C. K.

    2015-12-01

    The current work attempts to establish the criteria for powder material selection by investigating the influence of various powder-suspended dielectrics and machining parameters on various EDM characteristics of Inconel 625 (a nickel-based super alloy) which is nowadays regularly used in aerospace, chemical, and marine industries. The powders include aluminum (Al), graphite, and silicon (Si) that have significant variation in their thermo-physical characteristics. Results showed that powder properties like electrical conductivity, thermal conductivity, density, and hardness play a significant role in changing the machining performance and the quality of the machined surface. Among the three powders, highest material removal rate was observed for graphite powder due to its high electrical and thermal conductivities. Best surface finish and least radial overcut (ROC) were attained using Si powder. Maximum microhardness was found for Si due to its low thermal conductivity and high hardness. It is followed by graphite and aluminum powders. Addition of powder to the dielectric has increased the crater diameter due to expansion of plasma channel. Powder-mixed EDM (PMEDM) was also effective in lowering the density of surface cracks with least number of cracks obtained with graphite powder. X-ray diffraction analysis indicated possible formation of metal carbides along with grain growth phenomenon of Inconel 625 after PMEDM.

  7. Effect of Powder-Suspended Dielectric on the EDM Characteristics of Inconel 625

    NASA Astrophysics Data System (ADS)

    Talla, Gangadharudu; Gangopadhyay, S.; Biswas, C. K.

    2016-02-01

    The current work attempts to establish the criteria for powder material selection by investigating the influence of various powder-suspended dielectrics and machining parameters on various EDM characteristics of Inconel 625 (a nickel-based super alloy) which is nowadays regularly used in aerospace, chemical, and marine industries. The powders include aluminum (Al), graphite, and silicon (Si) that have significant variation in their thermo-physical characteristics. Results showed that powder properties like electrical conductivity, thermal conductivity, density, and hardness play a significant role in changing the machining performance and the quality of the machined surface. Among the three powders, highest material removal rate was observed for graphite powder due to its high electrical and thermal conductivities. Best surface finish and least radial overcut (ROC) were attained using Si powder. Maximum microhardness was found for Si due to its low thermal conductivity and high hardness. It is followed by graphite and aluminum powders. Addition of powder to the dielectric has increased the crater diameter due to expansion of plasma channel. Powder-mixed EDM (PMEDM) was also effective in lowering the density of surface cracks with least number of cracks obtained with graphite powder. X-ray diffraction analysis indicated possible formation of metal carbides along with grain growth phenomenon of Inconel 625 after PMEDM.

  8. Machining of bone: Analysis of cutting force and surface roughness by turning process.

    PubMed

    Noordin, M Y; Jiawkok, N; Ndaruhadi, P Y M W; Kurniawan, D

    2015-11-01

    There are millions of orthopedic surgeries and dental implantation procedures performed every year globally. Most of them involve machining of bones and cartilage. However, theoretical and analytical study on bone machining is lagging behind its practice and implementation. This study views bone machining as a machining process with bovine bone as the workpiece material. Turning process which makes the basis of the actually used drilling process was experimented. The focus is on evaluating the effects of three machining parameters, that is, cutting speed, feed, and depth of cut, to machining responses, that is, cutting forces and surface roughness resulted by the turning process. Response surface methodology was used to quantify the relation between the machining parameters and the machining responses. The turning process was done at various cutting speeds (29-156 m/min), depths of cut (0.03 -0.37 mm), and feeds (0.023-0.11 mm/rev). Empirical models of the resulted cutting force and surface roughness as the functions of cutting speed, depth of cut, and feed were developed. Observation using the developed empirical models found that within the range of machining parameters evaluated, the most influential machining parameter to the cutting force is depth of cut, followed by feed and cutting speed. The lowest cutting force was obtained at the lowest cutting speed, lowest depth of cut, and highest feed setting. For surface roughness, feed is the most significant machining condition, followed by cutting speed, and with depth of cut showed no effect. The finest surface finish was obtained at the lowest cutting speed and feed setting. PMID:26399875

  9. Machinability of lithium disilicate glass ceramic in in vitro dental diamond bur adjusting process.

    PubMed

    Song, Xiao-Fei; Ren, Hai-Tao; Yin, Ling

    2016-01-01

    Esthetic high-strength lithium disilicate glass ceramics (LDGC) are used for monolithic crowns and bridges produced in dental CAD/CAM and oral adjusting processes, which machinability affects the restorative quality. A machinability study has been made in the simulated oral clinical machining of LDGC with a dental handpiece and diamond burs, regarding the diamond tool wear and chip control, machining forces and energy, surface finish and integrity. Machining forces, speeds and energy in in vitro dental adjusting of LDGC were measured by a high-speed data acquisition and force sensor system. Machined LDGC surfaces were assessed using three-dimensional non-contact chromatic confocal optical profilometry and scanning electron microscopy (SEM). Diamond bur morphology and LDGC chip shapes were also examined using SEM. Minimum tool wear but significant LDGC chip accumulations were found. Machining forces and energy significantly depended on machining conditions (p<0.05) and were significantly higher than other glass ceramics (p<0.05). Machining speeds dropped more rapidly with increased removal rates than other glass ceramics (p<0.05). Two material machinability indices associated with the hardness, Young's modulus and fracture toughness were derived based on the normal force-removal rate relations, which ranked LDGC the most difficult to machine among glass ceramics. Surface roughness for machined LDGC was comparable for other glass ceramics. The removal mechanisms of LDGC were dominated by penetration-induced brittle fracture and shear-induced plastic deformation. Unlike most other glass ceramics, distinct intergranular and transgranular fractures of lithium disilicate crystals were found in LDGC. This research provides the fundamental data for dental clinicians on the machinability of LDGC in intraoral adjustments. PMID:26318569

  10. Search for a permanent EDM using laser cooled radioactive atom

    NASA Astrophysics Data System (ADS)

    Kawamura, Hirokazu; Ando, S.; Aoki, T.; Arikawa, H.; Ezure, S.; Harada, K.; Hayamizu, T.; Inoue, T.; Ishikawa, T.; Itoh, M.; Kato, K.; Kato, T.; Nataraj, H. S.; Sato, T.; Uchiyama, A.; Aoki, T.; Furukawa, T.; Hatakeyama, A.; Hatanaka, K.; Imai, K.; Murakami, T.; Shimizu, Y.; Wakasa, T.; Yoshida, H. P.; Sakemi, Y.

    2014-03-01

    The search for the electric-dipole moment (EDM) of laser-cooled francium (Fr) atoms could lead to a measurement for the electron EDM. It is predicted that the electron EDM would be enhanced by approximately three orders of magnitude in heavy atoms such as Fr. Laser-cooling and trapping techniques are expected to suppress statistical and systematic errors in precision measurements. The magneto-optical trap was achieved using stable rubidium in a developing factory of laser-cooled radioactive atoms. In light of the results from the rubidium experiments, we found that an upgrade of each apparatus is preferred for Fr trapping.

  11. PLANS FOR A NEUTRON EDM EXPERIMENT AT SNS

    SciTech Connect

    ITO, TAKEYASU

    2007-01-31

    The electric dipole moment of the neutron, leptons, and atoms provide a unique window to Physics Beyond the Standard Model. They are currently developing a new neutron EDM experiment (the nEDM Experiment). This experiment, which will be run at the 8.9 {angstrom} Neutron Line at the Fundamental Neutron Physics Beamline (FNPB) at the Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory, will search for the neutron EDM with a sensitivity two orders of magnitude higher than the present limit. In this paper, the motivation for the experiment, the experimental method, and the present status of the experiment are discussed.

  12. Progress toward an EDM measurement in {sup225}Ra.

    SciTech Connect

    Holt, R. J.; Ahmad, I.; Bailey, K.; Graner, B.; Greene, J. P.; Korsch, W.; Lu, Z.-T.; Mueller, P.; O'Connor, T. P.; Sulai, I. A.; Trimble, W. L.

    2010-11-01

    Permanent electric dipole moments (EDMs) in atoms or molecules are a signature of time-reversal and parity violation and represent an important window onto physics beyond the Standard Model. We are developing a next generation EDM search based on laser-cooled and trapped {sup 225}Ra atoms. Due to octupole deformation of the nucleus, {sup 225}Ra is predicted to be two to three orders of magnitude more sensitive to T-violating interactions than {sup 199}Hg, which currently sets the most stringent limits in the nuclear sector. We will discuss progress toward realizing a first EDM measurement for {sup 225}Ra.

  13. MUON EDM EXPERIMENT USING STAGE II OF THE NEUTRINO FACTORY.

    SciTech Connect

    FERNOW,R.C.; GALLARDO,J.C.; MORSE,W.M.; SEMERTZIDIS,Y.K.

    2002-07-01

    During the second stage of a future neutrino factory unprecedented numbers of bunched muons will become available. The cooled medium-energy muon beam could be used for a high sensitivity search for an electric dipole moment (EDM) of the muon with a sensitivity better than 10{sup -24}e {center_dot} cm. This will make the sensitivity of the EDM experiment to non-standard physics competitive and in many models more sensitive than the present limits on edms of the electron and nucleons. The experimental design exploits the strong motional electric field sensed by relativistic particles in a magnetic storage ring.

  14. Direct selective laser sintering of high performance metals: Machine design, process development and process control

    NASA Astrophysics Data System (ADS)

    Das, Suman

    1998-11-01

    This dissertation describes the development of an advanced manufacturing technology known as Direct Selective Laser Sintering (Direct SLS). Direct SLS is a laser based rapid manufacturing technology that enables production of functional, fully dense, metal and cermet components via the direct, layerwise consolidation of constituent powders. Specifically, this dissertation focuses on a new, hybrid net shape manufacturing technique known as Selective Laser Sintering/Hot Isostatic Pressing (SLS/HIP). The objective of research presented in this dissertation was to establish the fundamental machine technology and processing science to enable direct SLS fabrication of metal components composed of high performance, high temperature metals and alloys. Several processing requirements differentiate direct SLS of metals from SLS of polymers or polymer coated powders. Perhaps the most important distinguishing characteristic is the regime of high temperatures involved in direct SLS of metals. Biasing the temperature of the feedstock powder via radiant preheat prior to and during SLS processing was shown to be beneficial. Preheating the powder significantly influenced the flow and wetting characteristics of the melt. During this work, it was conclusively established that powder cleanliness is of paramount importance for successful layerwise consolidation of metal powders by direct SLS. Sequential trials were conducted to establish optimal bake-out and degas cycles under high vacuum. These cycles agreed well with established practices in the powder metallurgy industry. A study of some of the important transport mechanisms in direct SLS of metals was undertaken to obtain a fundamental understanding of the underlying process physics. This study not only provides an explanation of phenomena observed during SLS processing of a variety of metallic materials but also helps in developing selection schemes for those materials that are most amenable to direct SLS processing. The development of machine, processing and control technologies during this research effort enabled successful production of a number of integrally canned test specimens in Alloy 625 (InconelRTM 625 superalloy) and Ti-6Al-4V alloy. The overall goal of this research was to develop direct SLS of metals armed with a fundamental understanding of the underlying physics. The knowledge gained from experimental and analytical work is essential for three key objectives: machine design, process development and process control. (Abstract shortened by UMI.)

  15. Study on the nano machining process with a vibrating AFM tip on the polymer surface

    NASA Astrophysics Data System (ADS)

    Liu, Weitao; Yan, Yongda; Hu, Zhenjiang; Zhao, Xuesen; Yan, Jiucun; Dong, Shen

    2012-01-01

    The polymer has been proved to be nano machined by a vibrating tip in tapping mode of Atomic Force Microscope (AFM). The force between the tip and the surface is an important factor which determines success of the machining process. Controlling this force with high accuracy is the foundation of nanomachining in AFM tapping mode. To achieve a deeper understanding on this process, the tip is modeled as a driving oscillator with damping. Factors affecting the nano machining process are studied. The Hertz elastic contact theory is used to calculate the maximum contact pressure applied by the tip which is employed as a criterion to judge the deformation state of the sample. The simulation results show that: The driven amplitude can be used as a main parameter of controlling the machined depth. Sharper tips and harder cantilevers should be used for successful nanomachining with the vibrating tip. Under the same conditions, a larger tip radius will not only result in the machining error, but also lead to failure of the nanomachining process. The higher driving frequency will lead to a larger tapping force. However it cannot be used as a parameter to control the machined depth because of its narrow variation range. But it is a main error source for the nanomachining process in AFM tapping mode. Moreover, a larger Young's modulus polymer sample will induce a smaller machined depth, a larger maximum contact pressure and a bigger tapping force.

  16. Post-cast EDM method for reducing the thickness of a turbine nozzle wall

    DOEpatents

    Jones, Raymond Joseph; Bojappa, Parvangada Ganapathy; Kirkpatrick, Francis Lawrence; Schotsch, Margaret Jones; Rajan, Rajiv; Wei, Bin

    2002-01-01

    A post-cast EDM process is used to remove material from the interior surface of a nozzle vane cavity of a turbine. A thin electrode is passed through the cavity between opposite ends of the nozzle vane and displaced along the interior nozzle wall to remove the material along a predetermined path, thus reducing the thickness of the wall between the cavity and the external surface of the nozzle. In another form, an EDM process employing a profile as an electrode is disposed in the cavity and advanced against the wall to remove material from the wall until the final wall thickness is achieved, with the interior wall surface being complementary to the profile surface.

  17. Process automation using combinations of process and machine control technologies with application to a continuous dissolver

    SciTech Connect

    Spencer, B.B.: Yarbro, O.O.

    1991-01-01

    Operation of a continuous rotary dissolver, designed to leach uranium-plutonium fuel from chopped sections of reactor fuel cladding using nitric acid, has been automated. The dissolver is a partly continuous, partly batch process that interfaces at both ends with batchwise processes, thereby requiring synchronization of certain operations. Liquid acid is fed and flows through the dissolver continuously, whereas chopped fuel elements are fed to the dissolver in small batches and move through the compartments of the dissolver stagewise. Sequential logic (or machine control) techniques are used to control discrete activities such as the sequencing of isolation valves. Feedback control is used to control acid flowrates and temperatures. Expert systems technology is used for on-line material balances and diagnostics of process operation. 1 ref., 3 figs.

  18. The study of lepton EDM in CP violating BLMSSM

    NASA Astrophysics Data System (ADS)

    Zhao, Shu-Min; Feng, Tai-Fu; Zhan, Xi-Jie; Zhang, Hai-Bin; Yan, Ben

    2015-07-01

    In the supersymmetric model with local gauged baryon and lepton numbers (BLMSSM), the CP violating effects are considered to study the lepton electric dipole moment (EDM). The CP violating phases in BLMSSM are more than those in the standard model (SM) and can give large contributions. The analysis of the EDMs for the leptons e, μ, τ is shown in this work. It is in favour of exploring the source of CP violation and probing the physics beyond SM.

  19. An Investigation of Machining Characteristics in Micro-scale Milling Process

    SciTech Connect

    Ku, Min-Su; Kang, Ik-Soo; Kim, Jeong-Suk

    2011-01-17

    In this paper, an analytical solution of micro-scale milling process is presented in order to suggest available machining conditions. The size effect should be considered to determine cutting characteristics in micro-scale cutting. The feed per tooth is the most dominant cutting parameter related to the size effect in micro-scale milling process. In order to determine the feed per tooth at which chips can be formed, the finite element method is used. The finite element method is employed by utilizing the Johnson-Cook (JC) model as a constitutive model of work material flow stress. Machining experiments are performed to validate the simulation results by using a micro-machining stage. The validation is conducted by observing cutting force signals from a cutting tool and the conditions of the machined surface of the workpiece.

  20. An Investigation of Machining Characteristics in Micro-scale Milling Process

    NASA Astrophysics Data System (ADS)

    Ku, Min-Su; Kang, Ik-Soo; Kim, Jeong-Suk

    2011-01-01

    In this paper, an analytical solution of micro-scale milling process is presented in order to suggest available machining conditions. The size effect should be considered to determine cutting characteristics in micro-scale cutting. The feed per tooth is the most dominant cutting parameter related to the size effect in micro-scale milling process. In order to determine the feed per tooth at which chips can be formed, the finite element method is used. The finite element method is employed by utilizing the Johnson-Cook (JC) model as a constitutive model of work material flow stress. Machining experiments are performed to validate the simulation results by using a micro-machining stage. The validation is conducted by observing cutting force signals from a cutting tool and the conditions of the machined surface of the workpiece.

  1. Arabidopsis EDM2 promotes IBM1 distal polyadenylation and regulates genome DNA methylation patterns

    PubMed Central

    Lei, Mingguang; La, Honggui; Lu, Kun; Wang, Pengcheng; Miki, Daisuke; Ren, Zhizhong; Duan, Cheng-Guo; Wang, Xingang; Tang, Kai; Zeng, Liang; Yang, Lan; Zhang, Heng; Nie, Wenfeng; Liu, Pan; Zhou, Jianping; Liu, Renyi; Zhong, Yingli; Liu, Dong; Zhu, Jian-Kang

    2014-01-01

    DNA methylation is important for the silencing of transposons and other repetitive elements in many higher eukaryotes. However, plant and mammalian genomes have evolved to contain repetitive elements near or inside their genes. How these genes are kept from being silenced by DNA methylation is not well understood. A forward genetics screen led to the identification of the putative chromatin regulator Enhanced Downy Mildew 2 (EDM2) as a cellular antisilencing factor and regulator of genome DNA methylation patterns. EDM2 contains a composite Plant Homeo Domain that recognizes both active and repressive histone methylation marks at the intronic repeat elements in genes such as the Histone 3 lysine 9 demethylase gene Increase in BONSAI Methylation 1 (IBM1) and is necessary for maintaining the expression of these genes by promoting mRNA distal polyadenylation. Because of its role in maintaining IBM1 expression, EDM2 is required for preventing CHG methylation in the bodies of thousands of genes. Our results thus increase the understanding of antisilencing, genome methylation patterns, and regulation of alternative RNA processing by intronic heterochromatin. PMID:24248388

  2. Arabidopsis EDM2 promotes IBM1 distal polyadenylation and regulates genome DNA methylation patterns.

    PubMed

    Lei, Mingguang; La, Honggui; Lu, Kun; Wang, Pengcheng; Miki, Daisuke; Ren, Zhizhong; Duan, Cheng-Guo; Wang, Xingang; Tang, Kai; Zeng, Liang; Yang, Lan; Zhang, Heng; Nie, Wenfeng; Liu, Pan; Zhou, Jianping; Liu, Renyi; Zhong, Yingli; Liu, Dong; Zhu, Jian-Kang

    2014-01-01

    DNA methylation is important for the silencing of transposons and other repetitive elements in many higher eukaryotes. However, plant and mammalian genomes have evolved to contain repetitive elements near or inside their genes. How these genes are kept from being silenced by DNA methylation is not well understood. A forward genetics screen led to the identification of the putative chromatin regulator Enhanced Downy Mildew 2 (EDM2) as a cellular antisilencing factor and regulator of genome DNA methylation patterns. EDM2 contains a composite Plant Homeo Domain that recognizes both active and repressive histone methylation marks at the intronic repeat elements in genes such as the Histone 3 lysine 9 demethylase gene Increase in BONSAI Methylation 1 (IBM1) and is necessary for maintaining the expression of these genes by promoting mRNA distal polyadenylation. Because of its role in maintaining IBM1 expression, EDM2 is required for preventing CHG methylation in the bodies of thousands of genes. Our results thus increase the understanding of antisilencing, genome methylation patterns, and regulation of alternative RNA processing by intronic heterochromatin. PMID:24248388

  3. Installation and Implementation of an In-Process Coordinate Measuring Machine (CMM)

    SciTech Connect

    Johnston, Derek

    2008-06-16

    This report documents the work accomplished during the installation and implementation of the in-process Coordinate Measuring Machine (CMM) in Department A. A wealth of knowledge has been gained in solving the many technical issues that delayed the partial implementation of this CMM. The work completed thus far lead to the successfully calibrated in-process CMM workstation. A great deal of current and future work has been outlined in the following pages that shall be used as a guide for the full implementation of this CMM with machining processes in Department A.

  4. Microstructure, Morphology, and Nanomechanical Properties Near Fine Holes Produced by Electro-Discharge Machining

    SciTech Connect

    Blau, Peter Julian; Howe, Jane Y; Coffey, Dorothy W; Trejo, Rosa M; Kenik, Edward A; Jolly, Brian C; Yang, Nan

    2012-01-01

    Fine holes in metal alloys are employed for many important technological purposes, including cooling and the precise atomization of liquids. For example, they play an important role in the metering and delivery of fuel to the combustion chambers in energy-efficient, low-emissions diesel engines. Electro-discharge machining (EDM) is one process employed to produce such holes. Since the hole shape and bore morphology can affect fluid flow, and holes also represent structural discontinuities in the tips of the spray nozzles, it is important to understand the microstructures adjacent to these holes, the features of the hole walls, and the nanomechanical properties of the material that was in some manner altered by the EDM hole-making process. Several techniques were used to characterize the structure and properties of spray-holes in a commercial injector nozzle. These include scanning electron microscopy, cross-sectioning and metallographic etching, bore surface roughness measurements by optical interferometry, scanning electron microscopy, and transmission electron microscopy of recast EDM layers extracted with the help of a focused ion beam.

  5. Improved experimental limit on the EDM of 225Ra

    NASA Astrophysics Data System (ADS)

    Bishof, Michael; Bailey, Kevin; Dietrich, Matthew R.; Greene, John P.; Holt, Roy J.; Kalita, Mukut R.; Korsch, Wolfgang; Lemke, Nathan D.; Lu, Zheng-Tian; Mueller, Peter; O'Connor, Tom P.; Parker, Richard H.; Rabga, Tenzin; Singh, Jaideep T.

    2015-10-01

    Searches for permanent electric dipole moments (EDMs) in fundamental and composite particles are sensitive probes of beyond-standard-model symmetry violation that could explain the dominance of matter over anti-matter. The 225Ra (t1/2 = 15d, I = 1/2) atom is a particularly attractive system to use for an EDM measurement because its large nuclear octupole deformation, closely spaced ground-state parity doublet, and large atomic mass make 225Ra uniquely sensitive to symmetry-violating interactions in the nuclear medium. We have developed an experiment to measure the EDM of 225Ra and demonstrated the first ``proof-of-principle'' measurement, giving a 95% confidence upper limit of 5E-22 e-cm. After implementing a vacuum upgrade, we have observed nuclear spin coherence after 20 s of free evolution - a factor of ten improvement over our earlier results - and have lowered the 225Ra EDM limit by over an order of magnitude. Upcoming experimental upgrades have the potential to further improve our EDM sensitivity by many orders of magnitude, allowing us to test symmetry violation at an unprecedented level. This work is supported by U.S. DOE, Office of Science, Office of Nuclear Physics, under Contract DE-AC02-06CH11357.

  6. Direct processing of continuous fibers onto injection molding machines

    NASA Astrophysics Data System (ADS)

    Truckenmueller, F. M.

    1993-06-01

    A new injection molding process 'DIF' (Direct Incorporation of Continuous Fibers) is proposed whereby roving strands are directly incorporated into the polymer melt by using a reciprocating-screw-plasticating unit. The DIF-technology offers the possibility to substitute the relatively expensive pultrusion process which is used to produce long fiber pellets. Furthermore it can be used as a fast and flexible R&D tool. In order to improve fiber dispersion with minimum fiber breakage a new mixing non-return-valve 'LFMR' (Long Fiber Mixing Ring) was developed based on the 'Twente Mixing Ring'; Its mixing capacity and influence on processing characteristics, fiber breakage and property profile of the injection molded parts is examined and compared to a general purpose non-return-valve of the ring type. The results of fundamental mechanical and physical property investigations are presented including dispersion of fiber clusters and bundles, fiber length distribution and fiber orientation.

  7. Micromanufacturing Of Hard To Machine Materials By Physical And Chemical Ablation Processes

    SciTech Connect

    Schubert, A.; Edelmann, J.; Gross, S.; Meichsner, G.; Wolf, N.; Schneider, J.; Zeidler, H.; Hackert, M.

    2011-01-17

    Miniaturization leads to high requirements to the applied manufacturing processes especially in respect to the used hard to machine materials and the aims of structure size and geometrical accuracy. Traditional manufacturing processes reach their limits here. One alternative for these provide thermal and chemical ablation processes. These processes are applied for the production of different microstructures in different materials like hardened steel, carbides and ceramics especially for medical engineering and tribological applications.

  8. A new measurement of the 129Xe EDM

    NASA Astrophysics Data System (ADS)

    Chupp, Timothy; Degenkolb, Skyler; Sachdeva, Natasha; Cohn, Jared; Huneau, Jake; Singh, Jaideep; Fierlinger, Peter; Krageloh, Eva; Kuchler, Florian; Lins, Tobias; Marino, Mike; Meinel, Jonas; Niessen, Benjamin; Stuiber, Stefan; Sturm, Michael; Burghoff, Martin; Fan, Isaac; Kilian, Wolfgang; Knappe-Grueneberg, Silvia; Schnabel, Allard; Siefert, Frank; Trahms, Lutz; Voigt, Jens; Babcock, Earl; Salhi, Zahir; HeXe EDM Collaboration

    2015-10-01

    Although neutron, atom and molecular EDM measurements have set only upper limits, the motivation for more sensitive searches is stronger than ever. A recent global analysis of EDM results shows that the 95% CL upper limit of 6 ×10-27 e-cm for 129Xe contributes to constraining several CP violating parameters and that improved sensitivity further probes beyond-Standard-Model CP violation. In a new effort using a 3He co-magnetometer, the gas mixture is polarized by spin-exchange optical pumping and then transferred to a cell in the FRM-II high-performance magnetically shielded room, where a SQUID magnetometer array measures the spin precession. Recent tests indicate EDM sensitivity < 10-28 e-cm in one-day.

  9. 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.

  10. Search for a permanent EDM using laser cooled radioactive atom

    NASA Astrophysics Data System (ADS)

    Sakemi, Y.; Harada, K.; Hayamizu, T.; Itoh, M.; Kawamura, H.; Liu, S.; Nataraj, H. S.; Oikawa, A.; Saito, M.; Sato, T.; Yoshida, H. P.; Aoki, T.; Hatakeyama, A.; Murakami, T.; Imai, K.; Hatanaka, K.; Wakasa, T.; Shimizu, Y.; Uchida, M.

    2011-07-01

    An Electric Dipole Moment (EDM) of the elementary particle is a good prove to observe the phenomena beyond the Standard Model. A non-zero EDM shows the violation of the time reversal symmetry, and under the CPT invariance it means the CP violation. In paramagnetic atoms, an electron EDM results in an atomic EDM enhanced by the factor of the 3rd power of the charge of the nucleus due the relativistic effects. A heaviest alkali element francium (Fr), which is the radioactive atom, has the largest enhancement factor K ~ 895. Then, we are developing a high intensity laser cooled Fr factory at Cyclotron and Radioisotope Center (CYRIC), Tohoku University to perform the search for the EDM of Fr with the accuracy of 10-29 e · cm. The important points to overcome the current accuracy limit of the EDM are to realize the high intensity Fr source and to reduce the systematic error due to the motional magnetic field and inhomogeneous applied field. To reduce the dominant component of the systematic errors mentioned above, we will confine the Fr atoms in the small region with the Magneto-Optical Trap and optical lattice using the laser cooling and trapping techniques. The construction of the experimental apparatus is making progress, and the new thermal ionizer already produces the Fr of ~106 ions/s with the primary beam intensity 200 nA. The developments of the laser system and optical equipments are in progress, and the present status and future plan of the experimental project is reported.

  11. Search for a permanent EDM with laser cooled radioactive atom

    NASA Astrophysics Data System (ADS)

    Sakemi, Yasuhiro

    2014-09-01

    To explore the mechanism for the generation of the matter-antimatter asymmetry in the universe, the study on fundamental symmetry violation using the trapped radioactive atoms with laser cooling techniques is being promoted. An Electric Dipole Moment (EDM) of the elementary particle is a good prove to observe the phenomena beyond the Standard Model. A finite value of EDM means the violation of the time reversal symmetry, and the CP violation under the CPT invariance. In paramagnetic atoms, an electron EDM results in an atomic EDM enhanced by the factor of the 3rd power of the charge of the nucleus due the relativistic effects. A heaviest alkali element francium (Fr), which is the radioactive atom, has the largest enhancement factor K ~ 895 in atomic system. Then, we are developing a high intensity laser cooled Fr factory at Cyclotron and Radioisotope Center (CYRIC), Tohoku University to search for the EDM of Fr with the accuracy of 10-29 e cm. To overcome the current accuracy limit of the EDM, it is necessary to realize the high intensity Fr source and to reduce the systematic error due to the motional magnetic field and inhomogeneous applied field. To reduce the dominant component of the systematic errors mentioned above, we will confine the Fr atoms in the small region with the Magneto-Optical Trap (MOT) and optical lattice using the laser cooling and trapping techniques. The construction of the experimental apparatus is making progress, and the new thermal ionizer already produces the Fr of ~ 10 6 ions/s with the primary beam intensity 200 nA. The extracted Fr ion beam is transported to the neutralizer, which is located 10 m downstream, and the produced neutral Fr atoms are introduced into the MOT to load the next trapping system such as the optical dipole force trap and optical lattice. The coherence time will be increased in the laser trapping system, and the present status of the experiment will be reported.

  12. Machine learning and predictive data analytics enabling metrology and process control in IC fabrication

    NASA Astrophysics Data System (ADS)

    Rana, Narender; Zhang, Yunlin; Wall, Donald; Dirahoui, Bachir; Bailey, Todd C.

    2015-03-01

    Integrate circuit (IC) technology is going through multiple changes in terms of patterning techniques (multiple patterning, EUV and DSA), device architectures (FinFET, nanowire, graphene) and patterning scale (few nanometers). These changes require tight controls on processes and measurements to achieve the required device performance, and challenge the metrology and process control in terms of capability and quality. Multivariate data with complex nonlinear trends and correlations generally cannot be described well by mathematical or parametric models but can be relatively easily learned by computing machines and used to predict or extrapolate. This paper introduces the predictive metrology approach which has been applied to three different applications. Machine learning and predictive analytics have been leveraged to accurately predict dimensions of EUV resist patterns down to 18 nm half pitch leveraging resist shrinkage patterns. These patterns could not be directly and accurately measured due to metrology tool limitations. Machine learning has also been applied to predict the electrical performance early in the process pipeline for deep trench capacitance and metal line resistance. As the wafer goes through various processes its associated cost multiplies. It may take days to weeks to get the electrical performance readout. Predicting the electrical performance early on can be very valuable in enabling timely actionable decision such as rework, scrap, feedforward, feedback predicted information or information derived from prediction to improve or monitor processes. This paper provides a general overview of machine learning and advanced analytics application in the advanced semiconductor development and manufacturing.

  13. Neural-net Processed Electronic Holography for Rotating Machines

    NASA Technical Reports Server (NTRS)

    Decker, Arthur J.

    2003-01-01

    This report presents the results of an R&D effort to apply neural-net processed electronic holography to NDE of rotors. Electronic holography was used to generate characteristic patterns or mode shapes of vibrating rotors and rotor components. Artificial neural networks were trained to identify damage-induced changes in the characteristic patterns. The development and optimization of a neural-net training method were the most significant contributions of this work, and the training method and its optimization are discussed in detail. A second positive result was the assembly and testing of a fiber-optic holocamera. A major disappointment was the inadequacy of the high-speed-holography hardware selected for this effort, but the use of scaled holograms to match the low effective resolution of an image intensifier was one interesting attempt to compensate. This report also discusses in some detail the physics and environmental requirements for rotor electronic holography. The major conclusions were that neural-net and electronic-holography inspections of stationary components in the laboratory and the field are quite practical and worthy of continuing development, but that electronic holography of moving rotors is still an expensive high-risk endeavor.

  14. Cost-effective machining of brittle materials (glasses and ceramics) eliminating/minimizing the polishing process

    NASA Astrophysics Data System (ADS)

    Carlisle, Keith; Stocker, M. A.

    1997-09-01

    The disadvantages of traditional methods of edge grinding silicon wafers are discussed. With the industry's move to 300 mm format wafers, comes the pressure of environmental issues to minimize acid etch from the wafer process which is commonly used to improve surface finish and reduce sub surface damage. The recent work of Cranfield Precision in wafer edge processing is described, together with descriptions of a new grinding process and machine to eliminate grinding induced damage and minimize the polishing time.

  15. 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.

  16. Effect of processing parameters on surface finish for fused deposition machinable wax patterns

    NASA Technical Reports Server (NTRS)

    Roberts, F. E., III

    1995-01-01

    This report presents a study on the effect of material processing parameters used in layer-by-layer material construction on the surface finish of a model to be used as an investment casting pattern. The data presented relate specifically to fused deposition modeling using a machinable wax.

  17. Improved quality prediction model for multistage machining process based on geometric constraint equation

    NASA Astrophysics Data System (ADS)

    Zhu, Limin; He, Gaiyun; Song, Zhanjie

    2016-03-01

    Product variation reduction is critical to improve process efficiency and product quality, especially for multistage machining process (MMP). However, due to the variation accumulation and propagation, it becomes quite difficult to predict and reduce product variation for MMP. While the method of statistical process control can be used to control product quality, it is used mainly to monitor the process change rather than to analyze the cause of product variation. In this paper, based on a differential description of the contact kinematics of locators and part surfaces, and the geometric constraints equation defined by the locating scheme, an improved analytical variation propagation model for MMP is presented. In which the influence of both locator position and machining error on part quality is considered while, in traditional model, it usually focuses on datum error and fixture error. Coordinate transformation theory is used to reflect the generation and transmission laws of error in the establishment of the model. The concept of deviation matrix is heavily applied to establish an explicit mapping between the geometric deviation of part and the process error sources. In each machining stage, the part deviation is formulized as three separated components corresponding to three different kinds of error sources, which can be further applied to fault identification and design optimization for complicated machining process. An example part for MMP is given out to validate the effectiveness of the methodology. The experiment results show that the model prediction and the actual measurement match well. This paper provides a method to predict part deviation under the influence of fixture error, datum error and machining error, and it enriches the way of quality prediction for MMP.

  18. Etching process for improving the strength of a laser-machined silicon-based ceramic article

    DOEpatents

    Copley, S.M.; Tao, H.; Todd-Copley, J.A.

    1991-06-11

    A process is disclosed for improving the strength of laser-machined articles formed of a silicon-based ceramic material such as silicon nitride, in which the laser-machined surface is immersed in an etching solution of hydrofluoric acid and nitric acid for a duration sufficient to remove substantially all of a silicon film residue on the surface but insufficient to allow the solution to unduly attack the grain boundaries of the underlying silicon nitride substrate. This effectively removes the silicon film as a source of cracks that otherwise could propagate downwardly into the silicon nitride substrate and significantly reduce its strength. 1 figure.

  19. Etching process for improving the strength of a laser-machined silicon-based ceramic article

    DOEpatents

    Copley, Stephen M.; Tao, Hongyi; Todd-Copley, Judith A.

    1991-01-01

    A process for improving the strength of laser-machined articles formed of a silicon-based ceramic material such as silicon nitride, in which the laser-machined surface is immersed in an etching solution of hydrofluoric acid and nitric acid for a duration sufficient to remove substantially all of a silicon film residue on the surface but insufficient to allow the solution to unduly attack the grain boundaries of the underlying silicon nitride substrate. This effectively removes the silicon film as a source of cracks that otherwise could propagate downwardly into the silicon nitride substrate and significantly reduce its strength.

  20. Principles of image processing in machine vision systems for the color analysis of minerals

    NASA Astrophysics Data System (ADS)

    Petukhova, Daria B.; Gorbunova, Elena V.; Chertov, Aleksandr N.; Korotaev, Valery V.

    2014-09-01

    At the moment color sorting method is one of promising methods of mineral raw materials enrichment. This method is based on registration of color differences between images of analyzed objects. As is generally known the problem with delimitation of close color tints when sorting low-contrast minerals is one of the main disadvantages of color sorting method. It is can be related with wrong choice of a color model and incomplete image processing in machine vision system for realizing color sorting algorithm. Another problem is a necessity of image processing features reconfiguration when changing the type of analyzed minerals. This is due to the fact that optical properties of mineral samples vary from one mineral deposit to another. Therefore searching for values of image processing features is non-trivial task. And this task doesn't always have an acceptable solution. In addition there are no uniform guidelines for determining criteria of mineral samples separation. It is assumed that the process of image processing features reconfiguration had to be made by machine learning. But in practice it's carried out by adjusting the operating parameters which are satisfactory for one specific enrichment task. This approach usually leads to the fact that machine vision system unable to estimate rapidly the concentration rate of analyzed mineral ore by using color sorting method. This paper presents the results of research aimed at addressing mentioned shortcomings in image processing organization for machine vision systems which are used to color sorting of mineral samples. The principles of color analysis for low-contrast minerals by using machine vision systems are also studied. In addition, a special processing algorithm for color images of mineral samples is developed. Mentioned algorithm allows you to determine automatically the criteria of mineral samples separation based on an analysis of representative mineral samples. Experimental studies of the proposed algorithm were performed using samples of gold and copper-nickel ores. And obtained results confirmed its efficiency with respect to mineral objects. The research results will allow: expanding the use of the color sorting method in the field of mineral raw materials enrichment; facilitating the search for values of image processing features for machine vision systems which are used to the color analysis of minerals; reducing the time required for reconfiguration of image processing features when changing the type of analyzed minerals; realizing the process of rapid estimating the concentration rate of analyzed mineral ore by using color sorting method.

  1. Processing of rock core microtomography images: Using seven different machine learning algorithms

    NASA Astrophysics Data System (ADS)

    Chauhan, Swarup; Rühaak, Wolfram; Khan, Faisal; Enzmann, Frieder; Mielke, Philipp; Kersten, Michael; Sass, Ingo

    2016-01-01

    The abilities of machine learning algorithms to process X-ray microtomographic rock images were determined. The study focused on the use of unsupervised, supervised, and ensemble clustering techniques, to segment X-ray computer microtomography rock images and to estimate the pore spaces and pore size diameters in the rocks. The unsupervised k-means technique gave the fastest processing time and the supervised least squares support vector machine technique gave the slowest processing time. Multiphase assemblages of solid phases (minerals and finely grained minerals) and the pore phase were found on visual inspection of the images. In general, the accuracy in terms of porosity values and pore size distribution was found to be strongly affected by the feature vectors selected. Relative porosity average value of 15.92±1.77% retrieved from all the seven machine learning algorithm is in very good agreement with the experimental results of 17±2%, obtained using gas pycnometer. Of the supervised techniques, the least square support vector machine technique is superior to feed forward artificial neural network because of its ability to identify a generalized pattern. In the ensemble classification techniques boosting technique converged faster compared to bragging technique. The k-means technique outperformed the fuzzy c-means and self-organized maps techniques in terms of accuracy and speed.

  2. XCUT: A rule-based expert system for the automated process planning of machined parts

    SciTech Connect

    Brooks, S.L.; Hummel, K.E.; Wolf, M.L.

    1987-06-01

    Automated process planning is becoming a popular research and development topic in engineering and applied artificial intelligence. It is generally defined as the automatic planning of the manufacturing procedures for producing a part from a CAD based product definition. An automated process planning system, XCUT, is currently being developed using rule-based expert system techniques. XCUT will generate process plans for the production of machined piece-parts, given a geometric description of a part's features. The system currently is focused on operation planning for prismatic parts on multi-axis CNC milling machines. To date, moderately complex 2-1/2D prismatic parts have successfully been planned for with approximately 300 rules in the knowledge base. This paper will describe the XCUT system, system architecture, knowledge representation, plan development sequence, and issues in applying expert system technology to automated process planning. 16 refs.

  3. Dissipative processes and dust ion-acoustic shocks in a Q machine device

    SciTech Connect

    Popel, S.I.; Losseva, T.V.; Merlino, R.L.; Andreev, S.N.; Golub', A.P.

    2005-05-15

    A comparative analysis of the most important dissipative processes occurring during the excitation and propagation of dust ion-acoustic shocks in a Q machine device, among which are the charging of dust grains, the absorption of ions by grains, the transfer of the ion momentum to the grains, and Landau damping, is performed. The relative roles played by dissipative processes in different types of laboratory experiments with complex plasmas are estimated.

  4. Intermittent process measurement and process capability analysis using MP700 touch trigger probe on a CNC machining center

    NASA Astrophysics Data System (ADS)

    Shiou, Fang-Jung; Su, Po-Chuan

    2006-11-01

    This study developed an intermittent process measurement system by integrating a MP700 touch trigger probe system with a machining center to measure a workpiece containing freeform surface and regular geometric features, and to do the statistical process control analysis. The whole measuring system, consisting of a personal computer, a CNC machining center controller, a RENISHAW MP700 touch probe system, was integrated information-technically. Measuring software was also developed to simulate the measuring path, to prevent collision, to generate the corresponding measuring NC codes and to calculate the process capability indices, such as the process capability index (Cp), the process performance index (C PK) and the accuracy capability index (Ca). To evaluate the performance of the developed measuring system, a carrier combined with a freeform surface and regular geometric features, referred to in the ISO 10791-7 cutting test standard, was designed. Six pieces of the tested carriers were manufactured and inspected using the MP700 touch trigger probe to evaluate the performance of the developed measuring system. According to the measuring results, the developed measuring system was successfully and effectively used to carry out the intermittent process measurement and the statistical process analysis of the measuring results of some test carriers on the machining center.

  5. Auto-SEIA: simultaneous optimization of image processing and machine learning algorithms

    NASA Astrophysics Data System (ADS)

    Negro Maggio, Valentina; Iocchi, Luca

    2015-02-01

    Object classification from images is an important task for machine vision and it is a crucial ingredient for many computer vision applications, ranging from security and surveillance to marketing. Image based object classification techniques properly integrate image processing and machine learning (i.e., classification) procedures. In this paper we present a system for automatic simultaneous optimization of algorithms and parameters for object classification from images. More specifically, the proposed system is able to process a dataset of labelled images and to return a best configuration of image processing and classification algorithms and of their parameters with respect to the accuracy of classification. Experiments with real public datasets are used to demonstrate the effectiveness of the developed system.

  6. BRICORK: an automatic machine with image processing for the production of corks

    NASA Astrophysics Data System (ADS)

    Davies, Roger; Correia, Bento A. B.; Carvalho, Fernando D.; Rodrigues, Fernando C.

    1991-06-01

    The production of cork stoppers from raw cork strip is a manual and labour-intensive process in which a punch-operator quickly inspects all sides of the cork strip for defects and decides where to punch out stoppers. He then positions the strip underneath a rotating tubular cutter and punches out the stoppers one at a time. This procedure is somewhat subjective and prone to error, being dependent on the judgement and accuracy of the operator. This paper describes the machine being developed jointly by Mecanova, Laboratorio Nacional de Engenharia e Tecnologia (LNETI) and Empresa de Investiga&sigmafcoe Desenvolvimento de Electronica SA (EID) which automatically processes cork strip introduced by an unskilled operator. The machine uses both image processing and laser inspection techniques to examine the strip. Defects in the cork are detected and categorised in order to determine regions where stoppers may be punched. The precise locations are then automatically optimised for best usage of the raw material (quantity and quality of stoppers). In order to achieve the required speed of production these image processing techniques may be implemented in hardware. The paper presents results obtained using the vision system software under development together with descriptions of both the image processing and mechanical aspects of the proposed machine.

  7. 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.

  8. Observation of the Machine Transcription Process in the Word Processing Environment.

    ERIC Educational Resources Information Center

    Schwartz, Rose Ann; Remp, Ann Marie

    1983-01-01

    The objective of this study was to describe machine transcription in measurable terms for volume of keyboarding, materials handling, error correction, referencing activities, unit operation, and proofreading tasks. Descriptive statistics from the observation of 23 word processor operators are given. The observation device and its implications for

  9. Optimization process planning using hybrid genetic algorithm and intelligent search for job shop machining

    PubMed Central

    Salehi, Mojtaba

    2010-01-01

    Optimization of process planning is considered as the key technology for computer-aided process planning which is a rather complex and difficult procedure. A good process plan of a part is built up based on two elements: (1) the optimized sequence of the operations of the part; and (2) the optimized selection of the machine, cutting tool and Tool Access Direction (TAD) for each operation. In the present work, the process planning is divided into preliminary planning, and secondary/detailed planning. In the preliminary stage, based on the analysis of order and clustering constraints as a compulsive constraint aggregation in operation sequencing and using an intelligent searching strategy, the feasible sequences are generated. Then, in the detailed planning stage, using the genetic algorithm which prunes the initial feasible sequences, the optimized operation sequence and the optimized selection of the machine, cutting tool and TAD for each operation based on optimization constraints as an additive constraint aggregation are obtained. The main contribution of this work is the optimization of sequence of the operations of the part, and optimization of machine selection, cutting tool and TAD for each operation using the intelligent search and genetic algorithm simultaneously. PMID:21845020

  10. Modeling of the flow stress for AISI H13 Tool Steel during Hard Machining Processes

    NASA Astrophysics Data System (ADS)

    Umbrello, Domenico; Rizzuti, Stefania; Outeiro, José C.; Shivpuri, Rajiv

    2007-04-01

    In general, the flow stress models used in computer simulation of machining processes are a function of effective strain, effective strain rate and temperature developed during the cutting process. However, these models do not adequately describe the material behavior in hard machining, where a range of material hardness between 45 and 60 HRC are used. Thus, depending on the specific material hardness different material models must be used in modeling the cutting process. This paper describes the development of a hardness-based flow stress and fracture models for the AISI H13 tool steel, which can be applied for range of material hardness mentioned above. These models were implemented in a non-isothermal viscoplastic numerical model to simulate the machining process for AISI H13 with various hardness values and applying different cutting regime parameters. Predicted results are validated by comparing them with experimental results found in the literature. They are found to predict reasonably well the cutting forces as well as the change in chip morphology from continuous to segmented chip as the material hardness change.

  11. Modeling of the flow stress for AISI H13 Tool Steel during Hard Machining Processes

    SciTech Connect

    Umbrello, Domenico; Rizzuti, Stefania; Outeiro, Jose C.; Shivpuri, Rajiv

    2007-04-07

    In general, the flow stress models used in computer simulation of machining processes are a function of effective strain, effective strain rate and temperature developed during the cutting process. However, these models do not adequately describe the material behavior in hard machining, where a range of material hardness between 45 and 60 HRC are used. Thus, depending on the specific material hardness different material models must be used in modeling the cutting process. This paper describes the development of a hardness-based flow stress and fracture models for the AISI H13 tool steel, which can be applied for range of material hardness mentioned above. These models were implemented in a non-isothermal viscoplastic numerical model to simulate the machining process for AISI H13 with various hardness values and applying different cutting regime parameters. Predicted results are validated by comparing them with experimental results found in the literature. They are found to predict reasonably well the cutting forces as well as the change in chip morphology from continuous to segmented chip as the material hardness change.

  12. Optimization of Machining Process Parameters for Surface Roughness of Al-Composites

    NASA Astrophysics Data System (ADS)

    Sharma, S.

    2013-10-01

    Metal matrix composites (MMCs) have become a leading material among the various types of composite materials for different applications due to their excellent engineering properties. Among the various types of composites materials, aluminum MMCs have received considerable attention in automobile and aerospace applications. These materials are known as the difficult-to-machine materials because of the hardness and abrasive nature of reinforcement element-like silicon carbide particles. In the present investigation Al-SiC composite was produced by stir casting process. The Brinell hardness of the alloy after SiC addition had increased from 74 ± 2 to 95 ± 5 respectively. The composite was machined using CNC turning center under different machining parameters such as cutting speed (S), feed rate (F), depth of cut (D) and nose radius (R). The effect of machining parameters on surface roughness (Ra) was studied using response surface methodology. Face centered composite design with three levels of each factor was used for surface roughness study of the developed composite. A response surface model for surface roughness was developed in terms of main factors (S, F, D and R) and their significant interactions (SD, SR, FD and FR). The developed model was validated by conducting experiments under different conditions. Further the model was optimized for minimum surface roughness. An error of 3-7 % was observed in the modeled and experimental results. Further, it was fond that the surface roughness of Al-alloy at optimum conditions is lower than that of Al-SiC composite.

  13. 3D Machine Vision and Additive Manufacturing: Concurrent Product and Process Development

    NASA Astrophysics Data System (ADS)

    Ilyas, Ismet P.

    2013-06-01

    The manufacturing environment rapidly changes in turbulence fashion. Digital manufacturing (DM) plays a significant role and one of the key strategies in setting up vision and strategic planning toward the knowledge based manufacturing. An approach of combining 3D machine vision (3D-MV) and an Additive Manufacturing (AM) may finally be finding its niche in manufacturing. This paper briefly overviews the integration of the 3D machine vision and AM in concurrent product and process development, the challenges and opportunities, the implementation of the 3D-MV and AM at POLMAN Bandung in accelerating product design and process development, and discusses a direct deployment of this approach on a real case from our industrial partners that have placed this as one of the very important and strategic approach in research as well as product/prototype development. The strategic aspects and needs of this combination approach in research, design and development are main concerns of the presentation.

  14. Selection of Wire Electrical Discharge Machining Process Parameters on Stainless Steel AISI Grade-304 using Design of Experiments Approach

    NASA Astrophysics Data System (ADS)

    Lingadurai, K.; Nagasivamuni, B.; Muthu Kamatchi, M.; Palavesam, J.

    2012-06-01

    Wire electrical discharge machining (WEDM) is a specialized thermal machining process capable of accurately machining parts of hard materials with complex shapes. Parts having sharp edges that pose difficulties to be machined by the main stream machining processes can be easily machined by WEDM process. Design of Experiments approach (DOE) has been reported in this work for stainless steel AISI grade-304 which is used in cryogenic vessels, evaporators, hospital surgical equipment, marine equipment, fasteners, nuclear vessels, feed water tubing, valves, refrigeration equipment, etc., is machined by WEDM with brass wire electrode. The DOE method is used to formulate the experimental layout, to analyze the effect of each parameter on the machining characteristics, and to predict the optimal choice for each WEDM parameter such as voltage, pulse ON, pulse OFF and wire feed. It is found that these parameters have a significant influence on machining characteristic such as metal removal rate (MRR), kerf width and surface roughness (SR). The analysis of the DOE reveals that, in general the pulse ON time significantly affects the kerf width and the wire feed rate affects SR, while, the input voltage mainly affects the MRR.

  15. Kinematic Analysis of Cpm Machine Supporting to Rehabilitation Process after Surgical Knee Arthroscopy and Arthroplasty

    NASA Astrophysics Data System (ADS)

    Trochimczuk, R.; Kuźmierowski, T.

    2014-11-01

    Existing commercial solutions of the CPM (Continuous Passive Motion) machines are described in the paper. Based on the analysis of existing solutions we present our conceptual solution to support the process of rehabilitation of the knee joint which is necessary after arthroscopic surgery. For a given novel structure we analyze and present proprietary algorithms and the computer application to simulate the operation of our PCM device. In addition, we suggest directions for further research.

  16. Exploring the CP-violating NMSSM: EDM constraints and phenomenology

    NASA Astrophysics Data System (ADS)

    King, S. F.; Mühlleitner, M.; Nevzorov, R.; Walz, K.

    2015-12-01

    The Next-to-Minimal Supersymmetric extension of the Standard Model (NMSSM) features extra new sources for CP violation. In contrast to the MSSM CP violation can already occur at tree level in the Higgs sector. We investigate the range of possible allowed CP-violating phases by taking into account the constraints arising from the measurements of the Electric Dipole Moments (EDMs) and the latest LHC Higgs data. Our analysis shows that large CP-violating phases, that are NMSSM-specific, are not in conflict with the EDMs. They are dominantly constrained by the Higgs data in this case. We use our results to investigate the prospects of measuring CP violation through the combined measurement of Higgs rates, on the one hand, and in observables based on CP-violating Higgs couplings to tau leptons on the other hand.

  17. Numerical Modelling of Wire-EDM for Predicting Erosion Rate of Silicon

    NASA Astrophysics Data System (ADS)

    Joshi, Kamlesh; Sharma, Gaurav; Dongre, Ganesh; Joshi, Suhas Sitaram

    2016-05-01

    Recently, a lot of work is carried out in photovoltaic industry for slicing Si ingots using non-conventional technique like wire-EDM apart from conventional techniques like inner diameter saw and multi-wire saw. It is an emerging technology in field of Si wafer slicing and has a potential to be cost efficient. It reduces the kerf-loss and produces crack-free Si wafers. In general, the process of Si wafer cutting using wire-EDM is less understood due to its complex nature. In this work, the complex phenomena like formation of plasma channel, melting and erosion of Si material has been modelled mathematically. Further, the effect of input energy parameters like current, open voltage and pulse on-time on plasma and plasma-ingot interface temperature has been studied. The model is further extended along the length of the wire to evaluate the erosion depth and rate. The effect of process parameters on erosion depth and rate was validated experimentally. The model considers variation in material removal through the `plasma flushing efficiency'.

  18. The status of the Storage Ring EDM experiment

    SciTech Connect

    Semertzidis, Yannis K.

    2009-12-17

    The status of the storage ring experiment capable of probing the proton and deuteron EDM at the 10{sup -29} e.cm level is presented here. At this level it will be sensitive to a new physics mass scale of {approx}300 TeV. If there is new physics at the LHC, it will be sensitive to 10{mu}rad CP-violating phase level making it the most sensitive experiment for CP-violation beyond the SM.

  19. Design and Analysis of a Sensor System for Cutting Force Measurement in Machining Processes

    PubMed Central

    Liang, Qiaokang; Zhang, Dan; Coppola, Gianmarc; Mao, Jianxu; Sun, Wei; Wang, Yaonan; Ge, Yunjian

    2016-01-01

    Multi-component force sensors have infiltrated a wide variety of automation products since the 1970s. However, one seldom finds full-component sensor systems available in the market for cutting force measurement in machine processes. In this paper, a new six-component sensor system with a compact monolithic elastic element (EE) is designed and developed to detect the tangential cutting forces Fx, Fy and Fz (i.e., forces along x-, y-, and z-axis) as well as the cutting moments Mx, My and Mz (i.e., moments about x-, y-, and z-axis) simultaneously. Optimal structural parameters of the EE are carefully designed via simulation-driven optimization. Moreover, a prototype sensor system is fabricated, which is applied to a 5-axis parallel kinematic machining center. Calibration experimental results demonstrate that the system is capable of measuring cutting forces and moments with good linearity while minimizing coupling error. Both the Finite Element Analysis (FEA) and calibration experimental studies validate the high performance of the proposed sensor system that is expected to be adopted into machining processes. PMID:26751451

  20. Design and Analysis of a Sensor System for Cutting Force Measurement in Machining Processes.

    PubMed

    Liang, Qiaokang; Zhang, Dan; Coppola, Gianmarc; Mao, Jianxu; Sun, Wei; Wang, Yaonan; Ge, Yunjian

    2016-01-01

    Multi-component force sensors have infiltrated a wide variety of automation products since the 1970s. However, one seldom finds full-component sensor systems available in the market for cutting force measurement in machine processes. In this paper, a new six-component sensor system with a compact monolithic elastic element (EE) is designed and developed to detect the tangential cutting forces Fx, Fy and Fz (i.e., forces along x-, y-, and z-axis) as well as the cutting moments Mx, My and Mz (i.e., moments about x-, y-, and z-axis) simultaneously. Optimal structural parameters of the EE are carefully designed via simulation-driven optimization. Moreover, a prototype sensor system is fabricated, which is applied to a 5-axis parallel kinematic machining center. Calibration experimental results demonstrate that the system is capable of measuring cutting forces and moments with good linearity while minimizing coupling error. Both the Finite Element Analysis (FEA) and calibration experimental studies validate the high performance of the proposed sensor system that is expected to be adopted into machining processes. PMID:26751451

  1. A Voltage Multiplier for the nEDM Experiment

    NASA Astrophysics Data System (ADS)

    Bouman, Nathaniel; Stanislaus, Shirantha; Valpo nEDM Team

    2015-10-01

    The nEDM experiment at Oak Ridge National Laboratory aims to search for the electric dipole moment of the neutron (nEDM) at the 10-28 level. The experiment is currently at the research and development phase. One of the variables proportional to the sensitivity of the measurement is the strength of the electric field in the measurement cell where the effect of an nEDM is to be generated. The design of the experiment calls for an electric field of 75 kV/cm in this cell. A unique voltage multiplier involving a variable capacitor has been proposed to achieve this large required electric field. Electrostatic calculations using two independent software packages, COMSOL and Field Precision, were carried out to study the feasibility of the proposed voltage multiplier. A prototype of the electrodes and the voltage multiplier whose size was 25% of full size was also built to verify the predictions of the electrostatic calculations. Results of the tests with the prototype and the electrostatic calculations, will be presented.

  2. Measurement of large aspherical mirrors using coordinate measurement machine during the grinding process

    NASA Astrophysics Data System (ADS)

    Jing, Hongwei; Kuang, Long; Fan, Tianquan; Cao, Xuedong

    2006-02-01

    A new method has been developed to measure large aspherical mirrors accurately, quickly, and economically by using CMM (coordinate measurement machine). By using CMM to get the 3D coordinates of the actual points on the large aspherical mirrors and make bestfitting of actual surface and nominal surface, we can evaluate the surface of the large aspherical mirrors. It costs only 2 hours to measure an aspherical mirror with diameter larger than 1000mm. The results show good agreement with the results measured by Hartmann-Shack interferometer. Using this method, we can supervise the profile error to less than 5 μm PV during the grinding process. All the aspherical mirrors with dimensions within the range of the machine can be measured.

  3. A search engine for the engineering and equipment data management system (EDMS) at CERN

    NASA Astrophysics Data System (ADS)

    Tsyganov, A.; Amérigo, S. M.; Petit, S.; Pettersson, T.; Suwalska, A.

    2008-07-01

    CERN, the European Laboratory for Particle Physics, located in Geneva -Switzerland, is currently building the LHC (Large Hadron Collider), a 27 km particle accelerator. The equipment life-cycle management of this project is provided by the Engineering and Equipment Data Management System (EDMS [1] [2]) Service. Using an Oracle database, it supports the management and follow-up of different kinds of documentation through the whole life cycle of the LHC project: design, manufacturing, installation, commissioning data etc... The equipment data collection phase is now slowing down and the project is getting closer to the 'As-Built' phase: the phase of the project consuming and exploring the large volumes of data stored since 1996. Searching through millions of items of information (documents, equipment parts, operations...) multiplied by dozens of points of view (operators, maintainers...) requires an efficient and flexible search engine. This paper describes the process followed by the team to implement the search engine for the LHC As-built project in the EDMS Service. The emphasis is put on the design decision to decouple the search engine from any user interface, potentially enabling other systems to also use it. Projections, algorithms, and the planned implementation are described in this paper. The implementation of the first version started in early 2007.

  4. Electrochemical machining of super-hydrophobic Al surfaces and effect of processing parameters on wettability

    NASA Astrophysics Data System (ADS)

    Song, Jin-long; Xu, Wen-ji; Liu, Xin; Lu, Yao; Sun, Jing

    2012-09-01

    Super-hydrophobic aluminum (Al) surfaces were successfully fabricated via electrochemical machining in neutral NaClO3 electrolyte and subsequent fluoroalkylsilane (FAS) modification. The effects of the processing time, processing current density, and electrolyte concentration on the wettability, morphology, and roughness were studied. The surface morphology, chemical composition, and wettability of the Al surfaces were investigated using scanning electron microscopy (SEM) equipped with energy-dispersive spectroscopy (EDS), white-light interferometry, roughness measurements, X-ray diffraction (XRD), Fourier-transform infrared spectrometry (FTIR), and optical contact angle measurements. The results show that hierarchical rough structures and low surface energy films were present on the Al surfaces after electrochemical machining and FAS modification. The combination of the rough structures and the low surface energy materials plays a crucial role in achieving super-hydrophobicity. Compared with the anodic oxidation and chemical etching method, the method proposed in our work does not require strong acid or alkali, and causes less harm to the environment and operators but with high processing efficiency. The rough structures required by the super-hydrophobic surfaces were obtained at 30-s processing time and the best super-hydrophobicity with 164.6∘ water contact angle and 2∘ tilting angle was obtained at 360 s. The resulting super-hydrophobic Al surfaces have a long-time stability in air and an excellent resistance to corrosive liquids.

  5. Micro-electrical discharge machining of 3D micro-molds from Pd40Cu30P20Ni10 metallic glass by using laminated 3D micro-electrodes

    NASA Astrophysics Data System (ADS)

    Xu, Bin; Wu, Xiao-yu; Ma, Jiang; Liang, Xiong; Lei, Jian-guo; Wu, Bo; Ruan, Shuang-chen; Wang, Zhen-long

    2016-03-01

    For obtaining 3D micro-molds with better surface quality (slight ridges) and mechanical properties, in this paper 3D micro-electrodes were fabricated and applied to micro-electrical discharge machining (micro-EDM) to process Pd40Cu30P20Ni10 metallic glass. First, 100 μm-thick Cu foil was cut to obtain multilayer 2D micro-structures and these were connected to fit 3D micro-electrodes (with feature sizes of less than 1 mm). Second, under the voltage of 80 V, pulse frequency of 0.2MHZ, pulse width of 800 ns and pulse interval of 4200 ns, the 3D micro-electrodes were applied to micro-EDM for processing Pd40Cu30P20Ni10 metallic glass. The 3D micro-molds with feature within 1 mm were obtained. Third, scanning electron microscope, energy dispersive spectroscopy and x-ray diffraction analysis were carried out on the processed results. The analysis results indicate that with an increase in the depth of micro-EDM, carbon on the processed surface gradually increased from 0.5% to 5.8%, and the processed surface contained new phases (Ni12P5 and Cu3P).

  6. Modelling the surface generation process during AFM probe-based machining: simulation and experimental validation

    NASA Astrophysics Data System (ADS)

    Elkaseer, A.; Brousseau, E. B.

    2014-04-01

    The controlled removal of material conducted with the tip of an atomic force microscope (AFM) probe is a technique that has started gaining increased attention in recent years within the micro and nano manufacturing research community. The attractive characteristics of this process are that it is relatively simple to implement and low-cost compared with vacuum-based lithography techniques for micro and nano fabrication. However, similarly to any machining process, the resulting surface finish of features cut with an AFM probe can be critical. In this context, the focus of the paper is on the development and validation of a novel analytical model for predicting the floor surface roughness induced by AFM probe-based machining when generating cavities composed of linear parallel grooves. In addition to kinematic parameters, the proposed model takes into account the minimum chip thickness and elastic recovery associated with each phase present within the microstructure of a workpiece. The implementation of the model was carried out and its performance tested when processing a dual phase brass alloy using an AFM nano-indentation probe. A relatively good agreement was achieved between the analytical and experimental results with an average prediction error of 21% when assessing the arithmetic average roughness, Ra.

  7. A batch-mode micromachining process for spherical structures

    NASA Astrophysics Data System (ADS)

    Li, Tao; Visvanathan, Karthik; Gianchandani, Yogesh B.

    2014-02-01

    This paper reports a self-aligned three-dimensional process (3D-SOULE) that incorporates batch-mode micro ultrasonic machining (µUSM), lapping and micro electro-discharge machiningEDM) for fabrication of concave and mushroom-shaped spherical structures from hard and brittle materials. To demonstrate the process, 1 mm structures are fabricated from glass and ruby spheres. The µEDM technique is used to create the tool for μUSM from stainless steel spheres. Stainless steel 440, which provides a tool wear ratio <5%, is chosen as the tool material. A 2 × 2 array is used for batch processing. For an ultrasound generator frequency of 20 kHz and a vibration amplitude of 15 µm, machining rates of 24 and 12 µm min-1 are obtained for glass and ruby spheres, respectively. An approximate linear relationship is observed between the measured roughness (Ra) of the machined surface and the product of the fracture toughness (KIC) and the hardness (H) of the workpiece material (KIC3/2H1/2).

  8. Machine and Process System Diagnostics Using One-Step Prediction Maps

    SciTech Connect

    Breeding, J.E.; Damiano, B.; Tucker, R.W., Jr.

    1999-05-10

    This paper describes a method for machine or process system diagnostics that uses one-step prediction maps. The method uses nonlinear time series analysis techniques to form a one-step prediction map that estimates the next time series data point when given a sequence of previously measured time series data point. The difference between the predicted and measured time series values is a measure of the map error. The average value of this error should remain within some bound as long as both the dynamic system and its operating condition remain unchanged. However, changes in the dynamic system or operating condition will cause an increase in average map error. Thus, for a constant operating condition, monitoring the average map error over time should indicate when a change has occurred in the dynamic system. Furthermore, the map error itself forms a time series that can be analyzed to detect changes in system dynamics. The paper provides technical background in the nonlinear analysis techniques used in the diagnostic method, describes the creation of one-step prediction maps and their application to machine or process system diagnostics, and then presents results obtained from applying the diagnostic method to simulated and measured data.

  9. Machine Learning.

    ERIC Educational Resources Information Center

    Kirrane, Diane E.

    1990-01-01

    As scientists seek to develop machines that can "learn," that is, solve problems by imitating the human brain, a gold mine of information on the processes of human learning is being discovered, expert systems are being improved, and human-machine interactions are being enhanced. (SK)

  10. Complementarity of LHC and EDMs for exploring Higgs CP violation

    NASA Astrophysics Data System (ADS)

    Chen, Chien-Yi; Dawson, S.; Zhang, Yue

    2015-06-01

    We analyze the constraints on a CP-violating, flavor conserving, two Higgs doublet model from the measurements of Higgs properties and from the search for heavy Higgs bosons at LHC, and show that the stronger limits typically come from the heavy Higgs search channels. The limits on CP violation arising from the Higgs sector measurements are complementary to those from EDM measurements. Combining all current constraints from low energy to colliders, we set generic upper bounds on the CP violating angle which parametrizes the CP odd component in the 126 GeV Higgs boson.

  11. EDM 1.0: electron direct methods.

    PubMed

    Kilaas, R; Marks, L D; Own, C S

    2005-02-01

    A computer program designed to provide a number of quantitative analysis tools for high-resolution imaging and electron diffraction data is described. The program includes basic image manipulation, both real space and reciprocal space image processing, Wiener-filtering, symmetry averaging, methods for quantification of electron diffraction patterns and two-dimensional direct methods. The program consists of a number of sub-programs written in a combination of C++, C and Fortran. It can be downloaded either as GNU source code or as binaries and has been compiled and verified on a wide range of platforms, both Unix based and PC's. Elements of the design philosophy as well as future possible extensions are described. PMID:15639355

  12. 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.

  13. Simulation of abrasive flow machining process for 2D and 3D mixture models

    NASA Astrophysics Data System (ADS)

    Dash, Rupalika; Maity, Kalipada

    2015-12-01

    Improvement of surface finish and material removal has been quite a challenge in a finishing operation such as abrasive flow machining (AFM). Factors that affect the surface finish and material removal are media viscosity, extrusion pressure, piston velocity, and particle size in abrasive flow machining process. Performing experiments for all the parameters and accurately obtaining an optimized parameter in a short time are difficult to accomplish because the operation requires a precise finish. Computational fluid dynamics (CFD) simulation was employed to accurately determine optimum parameters. In the current work, a 2D model was designed, and the flow analysis, force calculation, and material removal prediction were performed and compared with the available experimental data. Another 3D model for a swaging die finishing using AFM was simulated at different viscosities of the media to study the effects on the controlling parameters. A CFD simulation was performed by using commercially available ANSYS FLUENT. Two phases were considered for the flow analysis, and multiphase mixture model was taken into account. The fluid was considered to be a

  14. Quantification of geologic lineaments by manual and machine processing techniques. [in Oklahoma and the Colorado Plateau

    NASA Technical Reports Server (NTRS)

    Podwysocki, M. H.; Moik, J. G.; Shoup, W. C.

    1975-01-01

    A study was conducted to investigate the effect of operator variability and subjectivity in lineament mapping and to examine methods to minimize or eliminate these problems by use of several machine preprocessing methods. LANDSAT scenes from the Anadarko Basin of Oklahoma and the Colorado Plateau were analyzed as test cases. Four geologists mapped lineaments on an Anadarko Basin scene, using transparencies of MSS bands 4-7, and their results are compared statistically. The total number of fractures mapped by the operators and their average lengths varied considerably, although comparison of lineament directions revealed some consensus. A summary map (785 linears) produced by overlaying the maps generated by the four operators showed that only 0.4% were recognized by all four operators, 4.7% by three, 17.8% by two and 77% by one operator. Two methods of machine aided mapping were tested, both simulating directional filters. One consists of computer (digital) processing of CCTs using edge enhancement algorithms, the other employs a television (analog) scanning of an image transparency which superimposes the original image and one offset in the direction of the scan line.

  15. GPS and EDM monitoring of Unzen volcano ground deformation

    NASA Astrophysics Data System (ADS)

    Matsushima, Takeshi; Takagi, Akimichi

    2000-11-01

    Following 198 years of dormancy, an eruption started at Mt. Fugen, the main peak of Unzen volcano, in Kyushu, Japan, in November 1990. A dacite lava dome began to grow in May 1991. We installed the surveying points of GPS in 1992 around the lava dome in order to observe the ground deformation that accompanied the growth of the lava dome. In the winters of 1993 and 1994, we observed swift ground deformations that radiated from the vent of the volcano. It was presumed that rising magma accumulated and expanded the volcano body. After the lava effusion stopped in 1995, we also installed surveying points on the lava dome. EDM mirrors were permanently fixed to the large rocks with bolts. A GPS survey was carried out 2 or 3 times each year to estimate the 3-dimensional displacement. The result of the EDM survey showed that the baselines from the flank of the volcano were shortening 5 mm per day, and the result of the GPS survey showed that the displacement vector of the dome was parallel to the direction of the steepest slope of the old volcano body. This indicates that the inside of the lava dome is still very hot, and that deformation of the dome is viscous.

  16. Restricted Boltzmann machine: a non-linear substitute for PCA in spectral processing

    NASA Astrophysics Data System (ADS)

    Bu, Yude; Zhao, Gang; Luo, A.-li; Pan, Jingchang; Chen, Yuqin

    2015-04-01

    Context. Principal component analysis (PCA) is widely used to repair incomplete spectra, to perform spectral denoising, and to reduce dimensionality. Presently, no method has been found to be comparable to PCA on these three problems. New methods have been proposed, but are often specific to one problem. For example, locally linear embedding outperforms PCA in dimensionality reduction. However, it cannot be used in spectral denoising and spectral reparing. Wavelet transform can be used to denoise spectra; however, it cannot be used in dimensionality reduction. Aims: We provide a new method that can substitute PCA in incomplete spectra repairing, spectral denoising and spectral dimensionality reduction. Methods: A new method, restricted Boltzmann machine (RBM), is introduced in spectral processing. RBM is a particular type of Markov random field with two-layer architecture, and use Gibbs sampling method to train the algorithm. It can be used in spectral denoising, dimensionality reduction and spectral repairing. Results: The performance of RBM is comparable to PCA in spectral processing. It can repair the incomplete spectra better: the difference between the RBM repaired spectra and the original spectra is smaller than that between the PCA repaired spectra and the original spectra. The denoised spectra given by RBM is similar to those given by PCA. In dimensionality reduction, RBM performs better than PCA: the classification results of RBM+ELM (i.e. the extreme learning machine) is higher than those of PCA+ELM. This shows that RBM can extract the spectral features more efficiently than PCA. Thus, RBM is a good alternative method for PCA in spectral processing. The source code of RBM algorithm is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/576/A96

  17. Machine vision process monitoring on a poultry processing kill line: results from an implementation

    NASA Astrophysics Data System (ADS)

    Usher, Colin; Britton, Dougl; Daley, Wayne; Stewart, John

    2005-11-01

    Researchers at the Georgia Tech Research Institute designed a vision inspection system for poultry kill line sorting with the potential for process control at various points throughout a processing facility. This system has been successfully operating in a plant for over two and a half years and has been shown to provide multiple benefits. With the introduction of HACCP-Based Inspection Models (HIMP), the opportunity for automated inspection systems to emerge as viable alternatives to human screening is promising. As more plants move to HIMP, these systems have the great potential for augmenting a processing facilities visual inspection process. This will help to maintain a more consistent and potentially higher throughput while helping the plant remain within the HIMP performance standards. In recent years, several vision systems have been designed to analyze the exterior of a chicken and are capable of identifying Food Safety 1 (FS1) type defects under HIMP regulatory specifications. This means that a reliable vision system can be used in a processing facility as a carcass sorter to automatically detect and divert product that is not suitable for further processing. This improves the evisceration line efficiency by creating a smaller set of features that human screeners are required to identify. This can reduce the required number of screeners or allow for faster processing line speeds. In addition to identifying FS1 category defects, the Georgia Tech vision system can also identify multiple "Other Consumer Protection" (OCP) category defects such as skin tears, bruises, broken wings, and cadavers. Monitoring this data in an almost real-time system allows the processing facility to address anomalies as soon as they occur. The Georgia Tech vision system can record minute-by-minute averages of the following defects: Septicemia Toxemia, cadaver, over-scald, bruises, skin tears, and broken wings. In addition to these defects, the system also records the length and width information of the entire chicken and different parts such as the breast, the legs, the wings, and the neck. The system also records average color and miss- hung birds, which can cause problems in further processing. Other relevant production information is also recorded including truck arrival and offloading times, catching crew and flock serviceman data, the grower, the breed of chicken, and the number of dead-on- arrival (DOA) birds per truck. Several interesting observations from the Georgia Tech vision system, which has been installed in a poultry processing plant for several years, are presented. Trend analysis has been performed on the performance of the catching crews and flock serviceman, and the results of the processed chicken as they relate to the bird dimensions and equipment settings in the plant. The results have allowed researchers and plant personnel to identify potential areas for improvement in the processing operation, which should result in improved efficiency and yield.

  18. An Approach to Realizing Process Control for Underground Mining Operations of Mobile Machines.

    PubMed

    Song, Zhen; Schunnesson, Håkan; Rinne, Mikael; Sturgul, John

    2015-01-01

    The excavation and production in underground mines are complicated processes which consist of many different operations. The process of underground mining is considerably constrained by the geometry and geology of the mine. The various mining operations are normally performed in series at each working face. The delay of a single operation will lead to a domino effect, thus delay the starting time for the next process and the completion time of the entire process. This paper presents a new approach to the process control for underground mining operations, e.g. drilling, bolting, mucking. This approach can estimate the working time and its probability for each operation more efficiently and objectively by improving the existing PERT (Program Evaluation and Review Technique) and CPM (Critical Path Method). If the delay of the critical operation (which is on a critical path) inevitably affects the productivity of mined ore, the approach can rapidly assign mucking machines new jobs to increase this amount at a maximum level by using a new mucking algorithm under external constraints. PMID:26062092

  19. An Approach to Realizing Process Control for Underground Mining Operations of Mobile Machines

    PubMed Central

    Song, Zhen; Schunnesson, Håkan; Rinne, Mikael; Sturgul, John

    2015-01-01

    The excavation and production in underground mines are complicated processes which consist of many different operations. The process of underground mining is considerably constrained by the geometry and geology of the mine. The various mining operations are normally performed in series at each working face. The delay of a single operation will lead to a domino effect, thus delay the starting time for the next process and the completion time of the entire process. This paper presents a new approach to the process control for underground mining operations, e.g. drilling, bolting, mucking. This approach can estimate the working time and its probability for each operation more efficiently and objectively by improving the existing PERT (Program Evaluation and Review Technique) and CPM (Critical Path Method). If the delay of the critical operation (which is on a critical path) inevitably affects the productivity of mined ore, the approach can rapidly assign mucking machines new jobs to increase this amount at a maximum level by using a new mucking algorithm under external constraints. PMID:26062092

  20. Dynamic Process Analysis In Cutting Zone During Machining Of Nickel Alloys

    NASA Astrophysics Data System (ADS)

    Czán, Andrej; Šajgalík, Michal; Martikáň, Anton; Mrázik, Jozef

    2015-12-01

    To generally improve effectivity of parts production and metal cutting process, there are used process models of super alloys together with finite element modeling simulations. Advanced measurement methods of the process could improve and verify the accuracy of these models. These methods cause many error sources when using empiric or exact methods such as infrared radiation thermography to measure the temperature distribution of the tool, workpiece, and chip during metal cutting. Measuring of metal machining is challenging due to factors such as the high magnification required, high surface speeds and deformations, micro-blackbody effects, changing emissivity and deformations present at metal cutting. As part of an ongoing effort to improve our understanding of uncertainties associated with these measurement methods, multimeasurement sets of experiments were performed. First set of measurements observed connection between surface temperature and the internal temperature of the cutting tool. This was accomplished by measuring the temperature using a thermal camera in cutting zone. Second set performed high-speed scan of dynamic processes such as formation of elastic and plastic deformation. During this operation was applied high-speed scannning system using macro conversion lens for monitoring of micro-structural changes in deformation areas. Next necessary applied set is recording of dynamic processes by implementation of piezoelectric measurement device for monitoring of cutting forces. The outputs from multimeasuring system are the basis for verification of theoretical knowledge from this field and elimination of uncertainties, which arise by using computer simulation systems.

  1. Simple, low-cost planar flow casting machine for rapid solidification processing

    NASA Astrophysics Data System (ADS)

    Smith, M. T.; Saletore, M.

    1986-08-01

    The design, fabrication, and operation of a relatively simple low-cost planar flow casting (PFC) machine optimized for small-batch processing were investigated by the Bureau of Mines. Several design features found beneficial to PFC process operation include: a ground nozzle stopper to retain the alloy charge during melting; a remote, large-volume pressure vessel connected to the crucible gas system to reduce temperature-induced pressure fluctuations; and the use of a nested induction coil that allows both the melt charge and the crucible reservoir to be located close to the cooling wheel. The results of several PFC process runs are provided showing typical values of the cooling wheel surface velocity, crucible ejection pressure, and crucible nozzle clearance gap. Examination of the rapidly solidified, Fe-based ribbons for thickness, dimensional uniformity, and atomic structure indicated that good quality glassy ribbon could be produced with proper selection of the controllable process variables. In addition, single-variable linear regression analysis was used to determined the effect of each process variable on the resulting ribbon thickness.

  2. Hybrid Metaheuristics for Solving a Fuzzy Single Batch-Processing Machine Scheduling Problem

    PubMed Central

    Molla-Alizadeh-Zavardehi, S.; Tavakkoli-Moghaddam, R.; Lotfi, F. Hosseinzadeh

    2014-01-01

    This paper deals with a problem of minimizing total weighted tardiness of jobs in a real-world single batch-processing machine (SBPM) scheduling in the presence of fuzzy due date. In this paper, first a fuzzy mixed integer linear programming model is developed. Then, due to the complexity of the problem, which is NP-hard, we design two hybrid metaheuristics called GA-VNS and VNS-SA applying the advantages of genetic algorithm (GA), variable neighborhood search (VNS), and simulated annealing (SA) frameworks. Besides, we propose three fuzzy earliest due date heuristics to solve the given problem. Through computational experiments with several random test problems, a robust calibration is applied on the parameters. Finally, computational results on different-scale test problems are presented to compare the proposed algorithms. PMID:24883359

  3. Image processing with genetic algorithm in a raisin sorting system based on machine vision

    NASA Astrophysics Data System (ADS)

    Abbasgholipour, Mahdi; Alasti, Behzad Mohammadi; Abbasgholipour, Vahdi; Derakhshan, Ali; Abbasgholipour, Mohammad; Rahmatfam, Sharmin; Rahmatfam, Sheyda; Habibifar, Rahim

    2012-04-01

    This study was undertaken to develop machine vision-based raisin detection technology. Supervised color image segmentation using a Permutation-coded Genetic Algorithm (GA) identifying regions in Hue-Saturation-Intensity (HSI) color space (GAHSI) for desired and undesired raisin detection was successfully implemented. Images were captured to explore the possibility of using GAHSI to locate desired raisin and undesired raisin regions in color space simultaneously. In this research, images were processed separately using three segmentation method, K-Means clustering in L*a*b* color space and GAHSI for single image, GA for single image in Red-Green-Blue (RGB) color space (GARGB). The GAHSI results provided evidence for the existence and separability of such regions. When compared with cluster analysis-based segmentation results, the GAHSI method showed no significant difference.

  4. FPGA implementation of hardware processing modules as coprocessors in brain-machine interfaces.

    PubMed

    Wang, Dong; Hao, Yaoyao; Zhu, Xiaoping; Zhao, Ting; Wang, Yiwen; Chen, Yaowu; Chen, Weidong; Zheng, Xiaoxiang

    2011-01-01

    Real-time computation, portability and flexibility are crucial for practical brain-machine interface (BMI) applications. In this work, we proposed Hardware Processing Modules (HPMs) as a method for accelerating BMI computation. Two HPMs have been developed. One is the field-programmable gate array (FPGA) implementation of spike sorting based on probabilistic neural network (PNN), and the other is the FPGA implementation of neural ensemble decoding based on Kalman filter (KF). These two modules were configured under the same framework and tested with real data from motor cortex recording in rats performing a lever-pressing task for water rewards. Due to the parallelism feature of FPGA, the computation time was reduced by several dozen times, while the results are almost the same as those from Matlab implementations. Such HPMs provide a high performance coprocessor for neural signal computation. PMID:22255365

  5. Man-machine interactive imaging and data processing using high-speed digital mass storage

    NASA Technical Reports Server (NTRS)

    Alsberg, H.; Nathan, R.

    1975-01-01

    The role of vision in teleoperation has been recognized as an important element in the man-machine control loop. In most applications of remote manipulation, direct vision cannot be used. To overcome this handicap, the human operator's control capabilities are augmented by a television system. This medium provides a practical and useful link between workspace and the control station from which the operator perform his tasks. Human performance deteriorates when the images are degraded as a result of instrumental and transmission limitations. Image enhancement is used to bring out selected qualities in a picture to increase the perception of the observer. A general purpose digital computer, an extensive special purpose software system is used to perform an almost unlimited repertoire of processing operations.

  6. Evaluation of surface water resources from machine-processing of ERTS multispectral data

    NASA Technical Reports Server (NTRS)

    Mausel, P. W.; Todd, W. J.; Baumgardner, M. F.; Mitchell, R. A.; Cook, J. P.

    1976-01-01

    The surface water resources of a large metropolitan area, Marion County (Indianapolis), Indiana, are studied in order to assess the potential value of ERTS spectral analysis to water resources problems. The results of the research indicate that all surface water bodies over 0.5 ha were identified accurately from ERTS multispectral analysis. Five distinct classes of water were identified and correlated with parameters which included: degree of water siltiness; depth of water; presence of macro and micro biotic forms in the water; and presence of various chemical concentrations in the water. The machine processing of ERTS spectral data used alone or in conjunction with conventional sources of hydrological information can lead to the monitoring of area of surface water bodies; estimated volume of selected surface water bodies; differences in degree of silt and clay suspended in water and degree of water eutrophication related to chemical concentrations.

  7. Synthesis CNTs Particle Based Abrasive Media for Abrasive Flow Machining Process

    NASA Astrophysics Data System (ADS)

    Kumar, Sonu; Murtaza, Q.; Walia, R. S.; Dhull, S.; Tyagi, P. K.

    2016-02-01

    Abrasive flow machining (AFM) is a modem fine finishing process used for intricate and internal finishing of components or parts. It is based on flowing of viscoelastic abrasive media over the surface to be fine finished. The abrasive media is the important parameter in the AFM process because of its ability to accurately abrade the predefined area along it flow path. In this study, an attempt is made to develop a new abrasive, alumina with Carbon non tubes (CNTs) in viscoelastic medium. CNT s in house produced through chemical vapour deposition technique and characterize through TEM. Performance evaluation of the new abrasive media is carried out by increasing content of CNT s with fixed extrusion pressure, viscosity of media and media flow rate as process parameters and surface finish improvement and material removal as process responses in AFM setup. Significantly improvement has been observed in material removal and maximum improvement of 100% has been observed in the surface finish on the inner cylindrical surface of the cast iron work piece.

  8. Butt weld inspection and weld machine diagnostic system for continuous coil processing lines

    SciTech Connect

    Lang, D.D.; Geier, D.; Shultz, B.L.

    1995-07-01

    Weld breaks of steel coil during cold rolling and continuous pickling operations are a significant source of lost productivity and product yield. Babcock and Wilcox Innerspec Technologies has developed and installed a weld process control system which monitors the key variables of the welding process and determines the quality of welds generated by flash-butt welding equipment. The TEMATE 2000 System utilizes Electro-Magnetic Acoustic Transducer (EMAT) technology as the basis for performing on-line, real-time, nondestructive weld quality evaluation. This technique accurately detects voids, laps, misalignment and over/under trim conditions in the weld. Results of the EMAT weld inspection are immediately presented to the weld machine operator for disposition. All weld quality and process parameter data are stored, traceable to each unique weld, and available for post process evaluation. Installation of the TEMATE 2000 system in a major flat rolled steel mill has contributed to near elimination of weld breakage and increased productivity at this facility.

  9. Focused particle beam nano-machining: the next evolution step towards simulation aided process prediction

    NASA Astrophysics Data System (ADS)

    Plank, Harald

    2015-02-01

    During the last decade, focused ion beam processing has been developed from traditionally used Ga+ liquid ion sources towards higher resolution gas field ion sources (He+ and Ne+). Process simulations not only improve the fundamental understanding of the relevant ion-matter interactions, but also enable a certain predictive power to accelerate advances. The historic ‘gold’ standard in ion-solid simulations is the SRIM/TRIM Monte Carlo package released by Ziegler, Ziegler and Biersack 2010 Nucl. Instrum. Methods B 268 1818-23. While SRIM/TRIM is very useful for a myriad of applications, it is not applicable for the understanding of the nanoscale evolution associated with ion beam nano-machining as the substrate does not evolve with the sputtering process. As a solution for this problem, a new, adapted simulation code is briefly overviewed and finally addresses these contributions. By that, experimentally observed Ne+ beam sputter profiles can be explained from a fundamental point of view. Due to their very good agreement, these simulations contain the potential for computer aided optimization towards predictable sputter processes for different nanotechnology applications. With these benefits in mind, the discussed simulation approach represents an enormous step towards a computer based master tool for adaptable ion beam applications in the context of industrial applications.

  10. Do two machine-learning based prognostic signatures for breast cancer capture the same biological processes?

    PubMed

    Drier, Yotam; Domany, Eytan

    2011-01-01

    The fact that there is very little if any overlap between the genes of different prognostic signatures for early-discovery breast cancer is well documented. The reasons for this apparent discrepancy have been explained by the limits of simple machine-learning identification and ranking techniques, and the biological relevance and meaning of the prognostic gene lists was questioned. Subsequently, proponents of the prognostic gene lists claimed that different lists do capture similar underlying biological processes and pathways. The present study places under scrutiny the validity of this claim, for two important gene lists that are at the focus of current large-scale validation efforts. We performed careful enrichment analysis, controlling the effects of multiple testing in a manner which takes into account the nested dependent structure of gene ontologies. In contradiction to several previous publications, we find that the only biological process or pathway for which statistically significant concordance can be claimed is cell proliferation, a process whose relevance and prognostic value was well known long before gene expression profiling. We found that the claims reported by others, of wider concordance between the biological processes captured by the two prognostic signatures studied, were found either to be lacking statistical rigor or were in fact based on addressing some other question. PMID:21423753

  11. Comparison of support vector machine-based processing chains for hyperspectral image classification

    NASA Astrophysics Data System (ADS)

    Rojas, Marta; Dópido, Inmaculada; Plaza, Antonio; Gamba, Paolo

    2010-08-01

    Many different approaches have been proposed in recent years for remotely sensed hyperspectral image classification. Despite the variety of techniques designed to tackle the aforementioned problem, the definition of standardized processing chains for hyperspectral image classification is a difficult objective, which may ultimately depend on the application being addressed. Generally speaking, a hyperspectral image classification chain may be defined from two perspectives: 1) the provider's viewpoint, and 2) the user's viewpoint, where the first part of the chain comprises activities such as data calibration and geo-correction aspects, while the second part of the chain comprises information extraction processes from the collected data. The modules in the second part of the chain (which constitutes our main focus in this paper) should be ideally flexible enough to be accommodated not only to different application scenarios, but also to different hyperspectral imaging instruments with varying characteristics, and spatial and spectral resolutions. In this paper, we evaluate the performance of different processing chains resulting from combinations of modules for dimensionality reduction, feature extraction/ selection, image classification, and spatial post-processing. The support vector machine (SVM) classifier is adopted as a baseline due to its ability to classify hyperspectral data sets using limited training samples. A specific classification scenario is investigated, using a reference hyperspectral data set collected by NASA's Airborne Visible Infra-Red Imaging Spectrometer (AVIRIS) over the Indian Pines region in Indiana, USA.

  12. 29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Occupations in the operation of power-driven meat-processing machines and occupations involving slaughtering, meat and poultry packing, processing, or... to Their Health or Well-Being § 570.61 Occupations in the operation of power-driven...

  13. 29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Occupations in the operation of power-driven meat-processing machines and occupations involving slaughtering, meat and poultry packing, processing, or... to Their Health or Well-Being § 570.61 Occupations in the operation of power-driven...

  14. 29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Occupations in the operation of power-driven meat-processing machines and occupations involving slaughtering, meat and poultry packing, processing, or rendering (Order 10). 570.61 Section 570.61 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS...

  15. 29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Occupations in the operation of power-driven meat-processing machines and occupations involving slaughtering, meat and poultry packing, processing, or... to Their Health or Well-Being § 570.61 Occupations in the operation of power-driven...

  16. One-step process for superhydrophobic metallic surfaces by wire electrical discharge machining.

    PubMed

    Bae, Won Gyu; Song, Ki Young; Rahmawan, Yudi; Chu, Chong Nam; Kim, Dookon; Chung, Do Kwan; Suh, Kahp Y

    2012-07-25

    We present a direct one-step method to fabricate dual-scale superhydrophobic metallic surfaces using wire electrical discharge machining (WEDM). A dual-scale structure was spontaneously formed by the nature of exfoliation characteristic of Al 7075 alloy surface during WEDM process. A primary microscale sinusoidal pattern was formed via a programmed WEDM process, with the wavelength in the range of 200 to 500 μm. Notably, a secondary roughness in the form of microcraters (average roughness, Ra: 4.16 to 0.41 μm) was generated during the exfoliation process without additional chemical treatment. The low surface energy of Al 7075 alloy (γ = 30.65 mJ/m(2)) together with the presence of dual-scale structures appears to contribute to the observed superhydrophobicity with a static contact angle of 156° and a hysteresis less than 3°. To explain the wetting characteristics on dual-scale structures, we used a simple theoretical model. It was found that Cassie state is likely to present on the secondary roughness in all fabricated surfaces. On the other hand, either Wenzel or Cassie state can present on the primary roughness depending on the characteristic length of sinusoidal pattern. In an optimal condition of the serial cutting steps with applied powers of ∼30 and ∼8 kW, respectively, a stable, superhydrophobic metallic surface was created with a sinusoidal pattern of 500 μm wavelength. PMID:22732181

  17. Allosteric regulation of E2:E3 interactions promote a processive ubiquitination machine

    PubMed Central

    Das, Ranabir; Liang, Yu-He; Mariano, Jennifer; Li, Jess; Huang, Tao; King, Aaren; Tarasov, Sergey G; Weissman, Allan M; Ji, Xinhua; Byrd, R Andrew

    2013-01-01

    RING finger proteins constitute the large majority of ubiquitin ligases (E3s) and function by interacting with ubiquitin-conjugating enzymes (E2s) charged with ubiquitin. How low-affinity RING–E2 interactions result in highly processive substrate ubiquitination is largely unknown. The RING E3, gp78, represents an excellent model to study this process. gp78 includes a high-affinity secondary binding region for its cognate E2, Ube2g2, the G2BR. The G2BR allosterically enhances RING:Ube2g2 binding and ubiquitination. Structural analysis of the RING:Ube2g2:G2BR complex reveals that a G2BR-induced conformational effect at the RING:Ube2g2 interface is necessary for enhanced binding of RING to Ube2g2 or Ube2g2 conjugated to Ub. This conformational effect and a key ternary interaction with conjugated ubiquitin are required for ubiquitin transfer. Moreover, RING:Ube2g2 binding induces a second allosteric effect, disrupting Ube2g2:G2BR contacts, decreasing affinity and facilitating E2 exchange. Thus, gp78 is a ubiquitination machine where multiple E2-binding sites coordinately facilitate processive ubiquitination. PMID:23942235

  18. Hybrid wavelet-support vector machine approach for modelling rainfall-runoff process.

    PubMed

    Komasi, Mehdi; Sharghi, Soroush

    2016-01-01

    Because of the importance of water resources management, the need for accurate modeling of the rainfall-runoff process has rapidly grown in the past decades. Recently, the support vector machine (SVM) approach has been used by hydrologists for rainfall-runoff modeling and the other fields of hydrology. Similar to the other artificial intelligence models, such as artificial neural network (ANN) and adaptive neural fuzzy inference system, the SVM model is based on the autoregressive properties. In this paper, the wavelet analysis was linked to the SVM model concept for modeling the rainfall-runoff process of Aghchai and Eel River watersheds. In this way, the main time series of two variables, rainfall and runoff, were decomposed to multiple frequent time series by wavelet theory; then, these time series were imposed as input data on the SVM model in order to predict the runoff discharge one day ahead. The obtained results show that the wavelet SVM model can predict both short- and long-term runoff discharges by considering the seasonality effects. Also, the proposed hybrid model is relatively more appropriate than classical autoregressive ones such as ANN and SVM because it uses the multi-scale time series of rainfall and runoff data in the modeling process. PMID:27120649

  19. Investigation of a novel hybrid process of laser drilling assisted with jet electrochemical machining

    NASA Astrophysics Data System (ADS)

    Zhang, Hua; Xu, Jiawen; Wang, Jiming

    2009-11-01

    Recast layer and spatter are two inherent defects commonly associated with holes produced with laser drilling. This paper reports a novel hybrid process of laser drilling assisted with jet electrochemical machining (JECM-LD) that aims to minimize such defects and improve the quality of laser-drilled holes. The process based on the application of a jet electrolyte, being aligned coaxially with the focused laser beam, on the workpiece surface during laser drilling. The effect of the jet electrolyte mainly is an electrochemical reaction with materials. The jet electrolyte also cools the workpiece and transports debris during the process. On the basis of a measurement of laser attenuation in electrolyte, an experimental apparatus system is made and JECM-LD experiments have been performed on 0.5-mm-thick 321S20 stainless steel with two lasers at wavelength of 1064 and 532 nm. It is shown that recast layer and spatter have been effectively reduced during the JECM-LD compared with laser drilling in ambient atmosphere conditions.

  20. A Search for the Electron EDM using Europium-Barium Titanates

    NASA Astrophysics Data System (ADS)

    Eckel, Stephen P.

    The discovery of a permanent electric dipole moment (EDM) of a fundamental particle would prove a great discovery in modern physics; such an EDM would violate two or three of the core symmetries of the fundamental forces of nature. Many models that go beyond the standard model of particle physics produce EDMs with magnitudes approaching the level detectable by the next generation of experiments. One possibility for such an experiment involves the use of a solid sample at low temperatures. In a paramagnetic material, the unpaired electrons, if they possess an EDM, can interact with the polarization of the sample and produce a magnetization that can be detected. This dissertation discusses an incarnation of such an experiment based on mixed europium-barium titanates. Such an experiment offers several advantages over other solid-state and atomic EDM searches including larger electron EDM induced interactions and the ability to measure without an applied electric field. This experiment has produced the world's best limit on the electron EDM to date from a solid sample, at |de| < 6.05 × 10-25 ecm (90% confidence limit). While this limit represents an improvement in the realm of solid-state experiments, it is not yet competitive with similar molecular and atomic experiments. However, there are many possibilities that could produce a superior solid-state experiment, and these will be discussed.

  1. Machine processing of S-192 and supporting aircraft data: Studies of atmospheric effects, agricultural classifications, and land resource mapping

    NASA Technical Reports Server (NTRS)

    Thomson, F.

    1975-01-01

    Two tasks of machine processing of S-192 multispectral scanner data are reviewed. In the first task, the effects of changing atmospheric and base altitude on the ability to machine-classify agricultural crops were investigated. A classifier and atmospheric effects simulation model was devised and its accuracy verified by comparison of its predicted results with S-192 processed results. In the second task, land resource maps of a mountainous area near Cripple Creek, Colorado were prepared from S-192 data collected on 4 August 1973.

  2. Effect of composition and processing on the thermal fatigue and toughness of high performance die steels. Final report

    SciTech Connect

    Wallace, J.F.; Wang, Y.; Schwam, D.

    1997-06-01

    The objective of this study was to improve average die life by optimizing die steel composition and the die processing. Four different steels, K,Q,C and Premium Grade H-13 have been investigated for thermal fatigue resistance and toughness. Optimum heat treatment processing has been determined for each steel with respect to austenitizing temperature and tempering conditions. The effect of the quenching rate on the thermal fatigue resistance and toughness of the die steels and the effect of Electro-Discharge Machining (EDM) on the thermal fatigue resistance were also determined. The immersion thermal fatigue specimen developed at CWRU was used to determine the thermal fatigue resistance as characterized by the two parameters of average maximum crack length and total crack area. The Charpy V-notch impact test was used over a -100{degrees}F to 450{degrees}F testing temperature range to evaluate the toughness and the brittle-ductile transition behavior. K steel has been identified as superior in performance compared to Premium Grade H-13. Q and C provide lower toughness and thermal fatigue resistance than H-13. Faster cooling rates provide higher thermal fatigue resistance and toughness. Higher austenitizing temperatures such as 1925{degrees}F compared to 1875{degrees}F provide better thermal fatigue resistance, but lower austenitizing temperatures of 1875{degrees}F provide better toughness. Higher hardness improves thermal fatigue resistance, but reduces toughness. A minimum of Rc 46 hardness is desired for aluminum die casting dies. EDM reduces the thermal fatigue resistance compared to conventional machining operations. When the EDM process of multiple small steps of decreasing energy and post-EDM treatments are employed, the effect can be reduced to a very slight amount. Preliminary evidence of the superior performance of the K steel has been provided by ongoing field testing of inserts in multiple cavity dies.

  3. Mathematical modeling and multi-criteria optimization of rotary electrical discharge machining process

    NASA Astrophysics Data System (ADS)

    Shrinivas Balraj, U.

    2015-12-01

    In this paper, mathematical modeling of three performance characteristics namely material removal rate, surface roughness and electrode wear rate in rotary electrical discharge machining RENE80 nickel super alloy is done using regression approach. The parameters considered are peak current, pulse on time, pulse off time and electrode rotational speed. The regression approach is very much effective in mathematical modeling when the performance characteristic is influenced by many variables. The modeling of these characteristics is helpful in predicting the performance under a given set of combination of input process parameters. The adequacy of developed models is tested by correlation coefficient and Analysis of Variance. It is observed that the developed models are adequate in establishing the relationship between input parameters and performance characteristics. Further, multi-criteria optimization of process parameter levels is carried using grey based Taguchi method. The experiments are planned based on Taguchi's L9 orthogonal array. The proposed method employs single grey relational grade as a performance index to obtain optimum levels of parameters. It is found that peak current and electrode rotational speed are influential on these characteristics. Confirmation experiments are conducted to validate optimal parameters and it reveals the improvements in material removal rate, surface roughness and electrode wear rate as 13.84%, 12.91% and 19.42% respectively.

  4. Efficient production by laser materials processing integrated into metal cutting machines

    NASA Astrophysics Data System (ADS)

    Wiedmaier, M.; Meiners, E.; Dausinger, Friedrich; Huegel, Helmut

    1994-09-01

    Beam guidance of high power YAG-laser (cw, pulsed, Q-switched) with average powers up to 2000 W by flexible glass fibers facilitates the integration of the laser beam as an additional tool into metal cutting machines. Hence, technologies like laser cutting, joining, hardening, caving, structuring of surfaces and laser-marking can be applied directly inside machining centers in one setting, thereby reducing the flow of workpieces resulting in a lowering of costs and production time. Furthermore, materials with restricted machinability--especially hard materials like ceramics, hard metals or sintered alloys--can be shaped by laser-caving or laser assisted machining. Altogether, the flexibility of laser integrated machining centers is substantially increased or the efficiency of a production line is raised by time-savings or extended feasibilities with techniques like hardening, welding or caving.

  5. Intensification of the Students' Self-Development Process When Performing Design and Settlement Works on the "Machine Parts" Course

    ERIC Educational Resources Information Center

    Timerbaev, Rais Mingalievich; Muhutdinov, Rafis Habreevich; Danilov, Valeriy Fedorovich

    2015-01-01

    The article addresses issues related to the methodology of intensifying self-development process when performing design and settlement works on the "Machine Parts" course for the students studying in such areas of training as "Technology" and "Vocational Education" with the use of computer technologies. At the same…

  6. Development of a neutralizer and the magneto optical trap system toward the EDM search

    NASA Astrophysics Data System (ADS)

    Aoki, Takahiro; Ando, Shun; Arikawa, Hiroshi; Ezure, Saki; Harada, Ken-Ichi; Hayamizu, Tomohiro; Inoue, Takeshi; Ishikawa, Taisuke; Itoh, Masatoshi; Kato, Ko; Sakemoto, Kosuke; Uchiyama, Aiko; Sakami, Yasuhiro

    2014-09-01

    If a non-zero electric dipole moment (EDM) is discovered, it suggests a CP violation that is important to explain the generation of matter dominant universe. To search for the electron EDM, we use Fr atoms that have a relatively simple electronic structure and a large enhancement factor of electron EDM. It is necessary to trap Fr atoms in a magneto-optical trap for EDM experiment. At present, searching for the resonance frequency of Fr atoms is undertaken. The experimental technique to trap and observe a small number of atoms is needed to search the resonance frequency. We have searched for parameters for trapping and observing the small number of atoms using Rb atoms whose resonance frequency is able to be fixed by using reference cell. In addition to this, studying of an yttrium neutralizer that is used for changing ions to neutral atoms is needed to trap as much Fr atoms as possible.

  7. Cost minimizing of cutting process for CNC thermal and water-jet machines

    NASA Astrophysics Data System (ADS)

    Tavaeva, Anastasia; Kurennov, Dmitry

    2015-11-01

    This paper deals with optimization problem of cutting process for CNC thermal and water-jet machines. The accuracy of objective function parameters calculation for optimization problem is investigated. This paper shows that working tool path speed is not constant value. One depends on some parameters that are described in this paper. The relations of working tool path speed depending on the numbers of NC programs frames, length of straight cut, configuration part are presented. Based on received results the correction coefficients for working tool speed are defined. Additionally the optimization problem may be solved by using mathematical model. Model takes into account the additional restrictions of thermal cutting (choice of piercing and output tool point, precedence condition, thermal deformations). At the second part of paper the non-standard cutting techniques are considered. Ones may lead to minimizing of cutting cost and time compared with standard cutting techniques. This paper considers the effectiveness of non-standard cutting techniques application. At the end of the paper the future research works are indicated.

  8. Seismic interpretation using Support Vector Machines implemented on Graphics Processing Units

    SciTech Connect

    Kuzma, H A; Rector, J W; Bremer, D

    2006-06-22

    Support Vector Machines (SVMs) estimate lithologic properties of rock formations from seismic data by interpolating between known models using synthetically generated model/data pairs. SVMs are related to kriging and radial basis function neural networks. In our study, we train an SVM to approximate an inverse to the Zoeppritz equations. Training models are sampled from distributions constructed from well-log statistics. Training data is computed via a physically realistic forward modeling algorithm. In our experiments, each training data vector is a set of seismic traces similar to a 2-d image. The SVM returns a model given by a weighted comparison of the new data to each training data vector. The method of comparison is given by a kernel function which implicitly transforms data into a high-dimensional feature space and performs a dot-product. The feature space of a Gaussian kernel is made up of sines and cosines and so is appropriate for band-limited seismic problems. Training an SVM involves estimating a set of weights from the training model/data pairs. It is designed to be an easy problem; at worst it is a quadratic programming problem on the order of the size of the training set. By implementing the slowest part of our SVM algorithm on a graphics processing unit (GPU), we improve the speed of the algorithm by two orders of magnitude. Our SVM/GPU combination achieves results that are similar to those of conventional iterative inversion in fractions of the time.

  9. Decoding semi-constrained brain activity from FMRI using support vector machines and gaussian processes.

    PubMed

    Schrouff, Jessica; Kussé, Caroline; Wehenkel, Louis; Maquet, Pierre; Phillips, Christophe

    2012-01-01

    Predicting a particular cognitive state from a specific pattern of fMRI voxel values is still a methodological challenge. Decoding brain activity is usually performed in highly controlled experimental paradigms characterized by a series of distinct states induced by a temporally constrained experimental design. In more realistic conditions, the number, sequence and duration of mental states are unpredictably generated by the individual, resulting in complex and imbalanced fMRI data sets. This study tests the classification of brain activity, acquired on 16 volunteers using fMRI, during mental imagery, a condition in which the number and duration of mental events were not externally imposed but self-generated. To deal with these issues, two classification techniques were considered (Support Vector Machines, SVM, and Gaussian Processes, GP), as well as different feature extraction methods (General Linear Model, GLM and SVM). These techniques were combined in order to identify the procedures leading to the highest accuracy measures. Our results showed that 12 data sets out of 16 could be significantly modeled by either SVM or GP. Model accuracies tended to be related to the degree of imbalance between classes and to task performance of the volunteers. We also conclude that the GP technique tends to be more robust than SVM to model unbalanced data sets. PMID:22563410

  10. Robust Brain-Machine Interface Design Using Optimal Feedback Control Modeling and Adaptive Point Process Filtering

    PubMed Central

    Carmena, Jose M.

    2016-01-01

    Much progress has been made in brain-machine interfaces (BMI) using decoders such as Kalman filters and finding their parameters with closed-loop decoder adaptation (CLDA). However, current decoders do not model the spikes directly, and hence may limit the processing time-scale of BMI control and adaptation. Moreover, while specialized CLDA techniques for intention estimation and assisted training exist, a unified and systematic CLDA framework that generalizes across different setups is lacking. Here we develop a novel closed-loop BMI training architecture that allows for processing, control, and adaptation using spike events, enables robust control and extends to various tasks. Moreover, we develop a unified control-theoretic CLDA framework within which intention estimation, assisted training, and adaptation are performed. The architecture incorporates an infinite-horizon optimal feedback-control (OFC) model of the brain’s behavior in closed-loop BMI control, and a point process model of spikes. The OFC model infers the user’s motor intention during CLDA—a process termed intention estimation. OFC is also used to design an autonomous and dynamic assisted training technique. The point process model allows for neural processing, control and decoder adaptation with every spike event and at a faster time-scale than current decoders; it also enables dynamic spike-event-based parameter adaptation unlike current CLDA methods that use batch-based adaptation on much slower adaptation time-scales. We conducted closed-loop experiments in a non-human primate over tens of days to dissociate the effects of these novel CLDA components. The OFC intention estimation improved BMI performance compared with current intention estimation techniques. OFC assisted training allowed the subject to consistently achieve proficient control. Spike-event-based adaptation resulted in faster and more consistent performance convergence compared with batch-based methods, and was robust to parameter initialization. Finally, the architecture extended control to tasks beyond those used for CLDA training. These results have significant implications towards the development of clinically-viable neuroprosthetics. PMID:27035820

  11. Robust Brain-Machine Interface Design Using Optimal Feedback Control Modeling and Adaptive Point Process Filtering.

    PubMed

    Shanechi, Maryam M; Orsborn, Amy L; Carmena, Jose M

    2016-04-01

    Much progress has been made in brain-machine interfaces (BMI) using decoders such as Kalman filters and finding their parameters with closed-loop decoder adaptation (CLDA). However, current decoders do not model the spikes directly, and hence may limit the processing time-scale of BMI control and adaptation. Moreover, while specialized CLDA techniques for intention estimation and assisted training exist, a unified and systematic CLDA framework that generalizes across different setups is lacking. Here we develop a novel closed-loop BMI training architecture that allows for processing, control, and adaptation using spike events, enables robust control and extends to various tasks. Moreover, we develop a unified control-theoretic CLDA framework within which intention estimation, assisted training, and adaptation are performed. The architecture incorporates an infinite-horizon optimal feedback-control (OFC) model of the brain's behavior in closed-loop BMI control, and a point process model of spikes. The OFC model infers the user's motor intention during CLDA-a process termed intention estimation. OFC is also used to design an autonomous and dynamic assisted training technique. The point process model allows for neural processing, control and decoder adaptation with every spike event and at a faster time-scale than current decoders; it also enables dynamic spike-event-based parameter adaptation unlike current CLDA methods that use batch-based adaptation on much slower adaptation time-scales. We conducted closed-loop experiments in a non-human primate over tens of days to dissociate the effects of these novel CLDA components. The OFC intention estimation improved BMI performance compared with current intention estimation techniques. OFC assisted training allowed the subject to consistently achieve proficient control. Spike-event-based adaptation resulted in faster and more consistent performance convergence compared with batch-based methods, and was robust to parameter initialization. Finally, the architecture extended control to tasks beyond those used for CLDA training. These results have significant implications towards the development of clinically-viable neuroprosthetics. PMID:27035820

  12. Towards the measurement of the electron EDM with laser cooled francium atoms

    NASA Astrophysics Data System (ADS)

    Kawamura, Hirokazu; Ando, S.; Aoki, T.; Arikawa, H.; Ezure, S.; Harada, K.; Hayamizu, T.; Inoue, T.; Ishikawa, T.; Itoh, M.; Kato, K.; Sakamoto, K.; Uchiyama, A.; Aoki, T.; Furukawa, T.; Hatakeyama, A.; Hatanaka, K.; Imai, K.; Murakami, T.; Nataraj, H. S.; Sato, T.; Shimizu, Y.; Yoshida, H. P.; Wakasa, T.; Sakemi, Y.

    2014-09-01

    The electric dipole moment (EDM) of a particle is a probe into new physics beyond the standard model. The electron EDM might be observed with an enhancement in heavier paramagnetic atoms. Francium (Fr), whose electron structure is useful for laser-cooling and trapping, has a large enhancement factor. Fr produced at high temperature via a fusion reaction will be laser-cooled and trapped in an optical lattice where the EDM is measured. The magneto-optical trapping of Fr is required in advance of the lattice trapping. The technique observing a small number of atoms makes it easy to search for the resonant frequency of Fr. The improvement of the beam purity should lead to a more efficient trap. The techniques towards Fr trapping and EDM measurement have been developed. The electric dipole moment (EDM) of a particle is a probe into new physics beyond the standard model. The electron EDM might be observed with an enhancement in heavier paramagnetic atoms. Francium (Fr), whose electron structure is useful for laser-cooling and trapping, has a large enhancement factor. Fr produced at high temperature via a fusion reaction will be laser-cooled and trapped in an optical lattice where the EDM is measured. The magneto-optical trapping of Fr is required in advance of the lattice trapping. The technique observing a small number of atoms makes it easy to search for the resonant frequency of Fr. The improvement of the beam purity should lead to a more efficient trap. The techniques towards Fr trapping and EDM measurement have been developed. Supported by MEXT/JSPS KAKENHI Grants (21104005, 25610112 and 26220705) and Tohoku University's Focused Research Project.

  13. New two-loop contributions to hadronic EDMs in the MSSM

    SciTech Connect

    Nagai, Minoru

    2007-11-20

    We discuss the quark EDMs and CEDMs in the MSSM with general flavor-changing terms in the squark mass matrices. In particular, the charged-Higgs mediated contributions to the down-quark EDM and CEDM are evaluated at two-loop level. We point out that these two-loop contributions may dominate over the one-loop induced gluino contribution even when the squark and gluino masses are around few TeV and tan {beta} is moderate.

  14. Effect of Carbon in the Dielectric Fluid and Workpieces on the Characteristics of Recast Layers Machined by Electrical Discharge Machining

    NASA Astrophysics Data System (ADS)

    Muttamara, Apiwat; Kanchanomai, Chaosuan

    2016-03-01

    Electrical discharge machining (EDM) is a popular non-traditional machining technique that is usually performed in kerosene. Carbon from the kerosene is mixed into the recast layer during EDM, increasing its hardness. EDM can be performed in deionized water, which causes decarburization. We studied the effects of carbon in the dielectric fluid and workpiece on the characteristics of recast layers. Experiments were conducted using gray cast iron and mild steel workpieces in deionized water or kerosene under identical operating conditions. Scanning electron microscopy revealed that the recast layer formed on gray iron was rougher than that produced on mild steel. Moreover, the dispersion of graphite flakes in the gray iron seemed to cause subsurface cracks, even when EDM was performed in deionized water. Dendritic structures and iron carbides were found in the recast layer of gray iron treated in deionized water. Kerosene caused more microcracks to form and increased surface roughness compared with deionized water. The microcrack length per unit area of mild steel treated in deionized water was greater than that treated in kerosene, but the cracks formed in kerosene were wider. The effect of the diffusion of carbon during cooling on the characteristics of the recast layer was discussed.

  15. Effect of Carbon in the Dielectric Fluid and Workpieces on the Characteristics of Recast Layers Machined by Electrical Discharge Machining

    NASA Astrophysics Data System (ADS)

    Muttamara, Apiwat; Kanchanomai, Chaosuan

    2016-06-01

    Electrical discharge machining (EDM) is a popular non-traditional machining technique that is usually performed in kerosene. Carbon from the kerosene is mixed into the recast layer during EDM, increasing its hardness. EDM can be performed in deionized water, which causes decarburization. We studied the effects of carbon in the dielectric fluid and workpiece on the characteristics of recast layers. Experiments were conducted using gray cast iron and mild steel workpieces in deionized water or kerosene under identical operating conditions. Scanning electron microscopy revealed that the recast layer formed on gray iron was rougher than that produced on mild steel. Moreover, the dispersion of graphite flakes in the gray iron seemed to cause subsurface cracks, even when EDM was performed in deionized water. Dendritic structures and iron carbides were found in the recast layer of gray iron treated in deionized water. Kerosene caused more microcracks to form and increased surface roughness compared with deionized water. The microcrack length per unit area of mild steel treated in deionized water was greater than that treated in kerosene, but the cracks formed in kerosene were wider. The effect of the diffusion of carbon during cooling on the characteristics of the recast layer was discussed.

  16. Feasibility demonstration of using wire electrical-discharge machining, abrasive flow honing, and laser spot welding to manufacture high-precision triangular-pitch Zircaloy-4 fuel-rod-support grids

    SciTech Connect

    Horwood, W.A.

    1982-05-01

    Results are reported supporting the feasibility of manufacturing high precision machined triangular pitch Zircaloy-4 fuel rod support grids for application in water cooled nuclear power reactors. The manufacturing processes investigated included wire electrical discharge machining of the fuel rod and guide tube cells in Zircaloy plate stock to provide the grid body, multistep pickling of the machined grid to provide smooth and corrosion resistant surfaces, and laser welding of thin Zircaloy cover plates to both sides of the grid body to capture separate AM-350 stainless steel insert springs in the grid body. Results indicated that dimensional accuracy better than +- 0.001 and +- 0.002 inch could be obtained on cell shape and position respectively after wire EDM and surface pickling. Results on strength, corrosion resistance, and internal quality of laser spot welds are provided.

  17. Investigation into the effect of overlap factors and process parameters on surface roughness and machined depth during micro-turning process with Nd:YAG laser

    NASA Astrophysics Data System (ADS)

    Kibria, G.; Doloi, B.; Bhattacharyya, B.

    2014-08-01

    One of the emerging laser material processing technologies to process cylindrical shaped materials is the laser micro-turning process. This process is used to machine micro-turned groove or surface on the difficult-to-process materials for a specific length of turn along its axis. The present experimental study investigates the laser micro-turning operation of a cylindrical shaped aluminum oxide (Al2O3) ceramic to explore the effect of successive spot overlap and circumferential overlap on the surface roughness (Ra) criterion. Moreover, depth of machining has also been studied by varying various process parameters such as pulse frequency, workpiece rotating speed and laser beam average power. Various amounts of spot overlap have been accomplished by different combined settings of related parameters i.e. workpiece rotating speed and pulse frequency. In contrast, various circumferential overlap between successive rotational scan widths have been achieved by varying the rotational speed and also axial feed rate of the workpiece. Surface roughness (Ra) and machined depth have been measured as output response for machining at various parametric combinations. Analyses have been made through different plots of surface roughness (Ra) and machined depth to study the influence of these overlaps and different process parameters. The experimental results revealed that surface roughness decreases with the increase of both the overlap factors. It is observed from the results that with the increase in circumferential overlap, roughness of the machined surface decreases for each workpiece rotating speed setting. Further, wide spot crater is achieved at a higher value of average power. Minimum surface roughness is achieved as 5.25 m at average power 10 W, pulse frequency 3000 Hz, workpiece rotating speed 400 rpm and Y feed rate 0.3 mm/s. The achieved machined depth is high at a low speed of rotation and pulse frequency settings. With the increase of average power of laser beam, the machined depth is found to increase linearly. The maximum micro-turning depth is achieved as 0.146 mm at parametric combination of average power of 10 W, pulse frequency of 3000 Hz, workpiece rotating speed of 400 rpm and Y feed rate of 0.3 mm/s.

  18. Colliding or co-rotating ion beams in storage rings for EDM search

    NASA Astrophysics Data System (ADS)

    Koop, I. A.

    2015-11-01

    A new approach to search for and measure the electric dipole moment (EDM) of the proton, deuteron and some other light nuclei is presented. The idea of the method is to store two ion beams, circulating with different velocities, in a storage ring with crossed electric and magnetic guiding fields. One beam is polarized and its EDM is measured using the so-called ‘frozen spin’ method. The second beam, which is unpolarized, is used as a co-magnetometer, sensitive to the radial component of the ring’s magnetic field. The particle’s magnetic dipole moment (MDM) couples to the radial magnetic field and mimics the EDM signal. Measuring the relative vertical orbit separation of the two beams, caused by the presence of the radial magnetic field, one can control the unwanted MDM spin precession. Examples of the parameters for EDM storage rings for protons and other species of ions are presented. The use of crossed electric and magnetic fields helps to reduce the size of the ring by a factor of 10-20. We show that the bending radius of such an EDM storage ring could be about 2-3 m. Finally, a new method of increasing the spin coherence time, the so-called ‘spin wheel’, is proposed and its applicability to the EDM search is discussed.

  19. Magnetic Field R&D for the neutron EDM experiment at TRIUMF

    NASA Astrophysics Data System (ADS)

    Mammei, Russell R.

    2014-09-01

    The neutron EDM experiment at TRIUMF aims to constrain the EDM with a precision of 1 ×10-27 e-cm by 2018. The experiment will use a spallation ultracold neutron (UCN) source employing superfluid helium coupled to a room-temperature EDM apparatus. In the previous best experiment, conducted at ILL, effects related to magnetic field homogeneity and instability were found to dominate the systematic error. This presentation will cover our R&D efforts on passive and active magnetic shielding, magnetic field generation within shielded volumes, and precision magnetometry. The neutron EDM experiment at TRIUMF aims to constrain the EDM with a precision of 1 ×10-27 e-cm by 2018. The experiment will use a spallation ultracold neutron (UCN) source employing superfluid helium coupled to a room-temperature EDM apparatus. In the previous best experiment, conducted at ILL, effects related to magnetic field homogeneity and instability were found to dominate the systematic error. This presentation will cover our R&D efforts on passive and active magnetic shielding, magnetic field generation within shielded volumes, and precision magnetometry. Supported by the Canada Foundation for Innovation, the Natural Sciences and Engineering Research Council of Canada, and the Canada Research Chairs program.

  20. Tool vibration detection with eddy current sensors in machining process and computation of stability lobes using fuzzy classifiers

    NASA Astrophysics Data System (ADS)

    Devillez, Arnaud; Dudzinski, Daniel

    2007-01-01

    Today the knowledge of a process is very important for engineers to find optimal combination of control parameters warranting productivity, quality and functioning without defects and failures. In our laboratory, we carry out research in the field of high speed machining with modelling, simulation and experimental approaches. The aim of our investigation is to develop a software allowing the cutting conditions optimisation to limit the number of predictive tests, and the process monitoring to prevent any trouble during machining operations. This software is based on models and experimental data sets which constitute the knowledge of the process. In this paper, we deal with the problem of vibrations occurring during a machining operation. These vibrations may cause some failures and defects to the process, like workpiece surface alteration and rapid tool wear. To measure on line the tool micro-movements, we equipped a lathe with a specific instrumentation using eddy current sensors. Obtained signals were correlated with surface finish and a signal processing algorithm was used to determine if a test is stable or unstable. Then, a fuzzy classification method was proposed to classify the tests in a space defined by the width of cut and the cutting speed. Finally, it was shown that the fuzzy classification takes into account of the measurements incertitude to compute the stability limit or stability lobes of the process.

  1. Automatic River Bed Grain Size Measurement Using Image Processing and Support Vector Machines

    NASA Astrophysics Data System (ADS)

    Bellugi, D.; Nelson, P. A.; Dietrich, W. E.

    2010-12-01

    Gravel-bedded rivers cut through hilly and mountainous areas, driving landscape evolution and creating a diverse habitat upon which river food web ecosystems develop. Our understanding of the mechanics underlying important processes in fluvial geomorphology, hydrodynamics, and aquatic ecology inevitably requires knowledge about the grain size distribution of river bed material. Standard methods of sampling bed surface material may introduce errors due to biases and inadequate sample size. Alternative areal or volumetric sampling procedures are often impractical, particularly in coarse channel beds. Furthermore, all invasive sampling techniques can compromise laboratory flume experiments. These concerns suggest that there is a practical need for a reliable, automated, non-invasive procedure for obtaining the grain size distribution of bed surface material. Although considerable effort has been made to automatically generate grain size distributions using image processing and analysis techniques, the problem remains quite challenging: issues such as varying lighting conditions, partial immersion of particles in water, and heterogeneous mineralogy result in ambiguities that cannot be easily resolved. Feature extraction introduces further biases due to over- or under-segmentation of the image. Moreover, unless the grain distributions are fairly homogeneous between different locations, and images are collected in similar fashion, it is difficult to parametrize any such method in a transferable manner. In this study we present an image processing and machine learning procedure to automatically identify and measure grains from photographic images of gravel-bedded rivers. We apply the state-of-the-art of image segmentation techniques, making use of local cues such as brightness, color, and texture in a multi-scale approach. These cues are globalized using a graph partitioning method on the oriented contour signal. The resulting boundary probability signal is treated by a region-merging procedure that avoids the artifacts of standard segmentation, providing a flexible hierarchical structure which allows us to progressively retain the grains which give us the greatest level of confidence, based on a learned decisional model. Our parameter-free procedure characterizes grain size distributions both quantitatively and spatially, enabling the tool to deliver a spatial grid of grain size distributions at multiple scales, the finest of which depends upon image resolution and sediment characteristics. We test the procedure on a unique data set composed of a high-resolution photographic survey of the bed surface of a near-field-scale flume in which diverse square patches of particles were removed and sieved to obtain precise measurements. The results show that this procedure effectively and automatically recovers particle size distributions and the spatial pattern of sorting processes acting on the bed.

  2. Modelling of the radial forging process of a hollow billet with the mandrel on the lever radial forging machine

    NASA Astrophysics Data System (ADS)

    Karamyshev, A. P.; Nekrasov, I. I.; Pugin, A. I.; Fedulov, A. A.

    2016-04-01

    The finite-element method (FEM) has been used in scientific research of forming technological process modelling. Among the others, the process of the multistage radial forging of hollow billets has been modelled. The model includes both the thermal problem, concerning preliminary heating of the billet taking into account thermal expansion, and the deformation problem, when the billet is forged in a special machine. The latter part of the model describes such features of the process as die calibration, die movement, initial die temperature, friction conditions, etc. The results obtained can be used to define the necessary process parameters and die calibration.

  3. Edme Mariotte (1620-1684): Pioneer of Neurophysiology.

    PubMed

    Grzybowski, Andrzej; Aydin, Pinar

    2007-01-01

    Edme Mariotte, a Roman Catholic priest and a founding member of l'Académie des sciences de Paris in 1666, is mainly remembered as the first scientist to discover the blind spot, known as Mariotte's Spot, in visual fields. His extensive work on optics and color perception is less well remembered. In addition, he made other important discoveries in different areas of science such as physics, mechanics, hydraulics, optics, plant physiology, meteorology, surveying, and research methodology. Mariotte was an active experimenter whose experimental principles separated science from metaphysics. His work was known to many of his fellow great scientists of his day, including Newton and Descartes, and his lengthy correspondence was a pioneering form of scientific international cooperation. Mariotte's observations, experiments, and demonstration of the blind spot led to a lively debate in the scientific community as to its explanation. Although he falsely assumed that it was the choroid, not the retina, that was the site of perception in the eye, he may be considered as a forerunner of neuro-ophthalmology due to his experiments and interest in the fundus. PMID:17574069

  4. Quantification of Geologic Lineaments by Manual and Machine Processing Techniques. [Landsat satellites - mapping/geological faults

    NASA Technical Reports Server (NTRS)

    Podwysocki, M. H.; Moik, J. G.; Shoup, W. C.

    1975-01-01

    The effect of operator variability and subjectivity in lineament mapping and methods to minimize or eliminate these problems by use of several machine preprocessing methods was studied. Mapped lineaments of a test landmass were used and the results were compared statistically. The total number of fractures mapped by the operators and their average lengths varied considerably, although comparison of lineament directions revealed some consensus. A summary map (785 linears) produced by overlaying the maps generated by the four operators shows that only 0.4 percent were recognized by all four operators, 4.7 percent by three, 17.8 percent by two, and 77 percent by one operator. Similar results were obtained in comparing these results with another independent group. This large amount of variability suggests a need for the standardization of mapping techniques, which might be accomplished by a machine aided procedure. Two methods of machine aided mapping were tested, both simulating directional filters.

  5. Electrical discharge machining of type-N(f) microwave connectors

    SciTech Connect

    Haushalter, R.J.

    1996-07-01

    A particular out-of-specification mechanical dimension on Type-N(f) [Type-N(female)] microwave connectors sometimes disqualifies otherwise perfectly acceptable microwave devices from being used in calibration systems. The Miniature Machining Group at Sandia National Laboratories applied a technique called Electrical Discharge Machining (EDM) to quickly and economically machine these devices without disassembly. In so doing, they facilitated the use of existing components without the need to purchase new devices. The technique also improves an uncertainty of calibration known as Mismatch Uncertainty by optimizing the reflection coefficient of the calibration test port. This effects a reduction in overall calibration uncertainties.

  6. Analysis of the effects of different machining processes on sealing using multiscale topography

    NASA Astrophysics Data System (ADS)

    Deltombe, Raphael; Bigerelle, Maxence; Jourani, Abdeljalil

    2016-03-01

    This study characterizes seal performance using a multiscale analysis of surface topography. The performance of two surface morphologies is compared: the first one is obtained with machining only and leads to leakage while the second one is obtained with machining and superfinishing and prevents leakage. It is shown that conventional roughness analysis does not enable to identify the differences between both surfaces. Only the use of a new parameter, the order parameter, and the use of a multiscale analysis of surfaces enable to distinguish the studied surfaces and to identify leakage causes. These causes are checked using a numerical contact simulation. It is shown that microroughness plays a major role in leakage.

  7. Study of machining process computer simulation of a NC-WEDM-HS system of two turning coordinates

    NASA Astrophysics Data System (ADS)

    Ren, Fujun; Huang, Dechen; Liu, Jinchun

    2005-12-01

    In order to raise the productivity and precision of Numeric Control-Wire Cut Electric Discharge Machining with High Speed (NC-WEDM-HS) system of two turning coordinates, the basic idea of simulation of the machining process of this machining system was introduced. The characteristics and general laws of cutting complex curved surfaces by the NC-WEDM-HS system of two turning coordinates were systematically analyzed. The motion parameters and motion forms of the NC-WEDM-HS system of two turning coordinates were also analyzed. The universal mathematical models of the NC-WEDM-HS system of two turning coordinates were derived. Many simulating programs were designed. Experiments on cutting complex curved surface by the NC-WEDM-HS system of two turning coordinates were conducted and many complex curved surface parts were machined. Good simulation results were obtained. Expected results were achieved. The application of this simulating technology was depicted. All these works provide an effective approach to resolve the problems of cutting complex curved surface parts by the mathematical models of the NC-WEDM-HS system.

  8. An Insight to the Modeling of 1 × 1 Rib Loop Formation Process on Circular Weft Knitting Machine using Computer

    NASA Astrophysics Data System (ADS)

    Ray, Sadhan Chandra

    2015-10-01

    The mechanics of single jersey loop formation is well-reported is literature. However, as the concept of any model of double jersey loop formation process is not available in accessible international literature. Therefore, it was planned to develop a model of 1 × 1 rib loop formation process on dial and cylinder machine using computer so that the influence of various input variables on the final loop length as well on the profile of tension on the yarn inside Knitting Zone (KZ) can be understood. The model provides an insight into the mechanics of 1 × 1 rib loop formation system on dial and cylinder machine. Besides, the degree of agreement between predicted and measured values of loop length and cam forces as well as theoretical analysis of the model have justified the acceptability of the model.

  9. 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…

  10. 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.

  11. 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

  12. Charging machine

    DOEpatents

    Medlin, John B.

    1976-05-25

    A charging machine for loading fuel slugs into the process tubes of a nuclear reactor includes a tubular housing connected to the process tube, a charging trough connected to the other end of the tubular housing, a device for loading the charging trough with a group of fuel slugs, means for equalizing the coolant pressure in the charging trough with the pressure in the process tubes, means for pushing the group of fuel slugs into the process tube and a latch and a seal engaging the last object in the group of fuel slugs to prevent the fuel slugs from being ejected from the process tube when the pusher is removed and to prevent pressure liquid from entering the charging machine.

  13. Intelligent Machines in the 21st Century: Automating the Processes of Inference and Inquiry

    NASA Technical Reports Server (NTRS)

    Knuth, Kevin H.

    2003-01-01

    The last century saw the application of Boolean algebra toward the construction of computing machines, which work by applying logical transformations to information contained in their memory. The development of information theory and the generalization of Boolean algebra to Bayesian inference have enabled these computing machines. in the last quarter of the twentieth century, to be endowed with the ability to learn by making inferences from data. This revolution is just beginning as new computational techniques continue to make difficult problems more accessible. However, modern intelligent machines work by inferring knowledge using only their pre-programmed prior knowledge and the data provided. They lack the ability to ask questions, or request data that would aid their inferences. Recent advances in understanding the foundations of probability theory have revealed implications for areas other than logic. Of relevance to intelligent machines, we identified the algebra of questions as the free distributive algebra, which now allows us to work with questions in a way analogous to that which Boolean algebra enables us to work with logical statements. In this paper we describe this logic of inference and inquiry using the mathematics of partially ordered sets and the scaffolding of lattice theory, discuss the far-reaching implications of the methodology, and demonstrate its application with current examples in machine learning. Automation of both inference and inquiry promises to allow robots to perform science in the far reaches of our solar system and in other star systems by enabling them to not only make inferences from data, but also decide which question to ask, experiment to perform, or measurement to take given what they have learned and what they are designed to understand.

  14. On Electro Discharge Machining of Inconel 718 with Hollow Tool

    NASA Astrophysics Data System (ADS)

    Rajesha, S.; Sharma, A. K.; Kumar, Pradeep

    2012-06-01

    Inconel 718 is a nickel-based alloy designed for high yield, tensile, and creep-rupture properties. This alloy has been widely used in jet engines and high-speed airframe parts in aeronautic application. In this study, electric discharge machining (EDM) process was used for machining commercially available Inconel 718. A copper electrode with 99.9% purity having tubular cross section was employed to machine holes of 20 mm height and 12 mm diameter on Inconel 718 workpieces. Experiments were planned using response surface methodology (RSM). Effects of five major process parameters—pulse current, duty factor, sensitivity control, gap control, and flushing pressure on the process responses—material removal rate (MRR) and surface roughness (SR) have been discussed. Mathematical models for MRR and SR have been developed using analysis of variance. Influences of process parameters on tool wear and tool geometry have been presented with the help of scanning electron microscope (SEM) micrographs. Analysis shows significant interaction effect of pulse current and duty factor on MRR yielding a wide range from 14.4 to 22.6 mm3/min, while pulse current remains the most contributing factor with approximate changes in the MRR and SR of 48 and 37%, respectively, corresponding to the extreme values considered. Interactions of duty factor and flushing pressure yield a minimum surface roughness of 6.2 μm. The thickness of the sputtered layer and the crack length were found to be functions of pulse current. The hollow tool gets worn out on both the outer and the inner edges owing to spark erosion as well as abrasion due to flow of debris.

  15. The Chasm Green Machine: A Rapid Data Acquisition and Mapping System For Direct Observation of Shallow Hydrological Processes.

    NASA Astrophysics Data System (ADS)

    Quinn, P.; Merrett, S.

    CHASM (Catchment Hydrology and Sustainable Management) is a major UK funded project investigating all aspects of hydrological observation from point to basin scale. The project includes a mobile instrumentation component, which is now referred to as the 'Green Machine'. This research facility includes an All Terrain Vehicle, an on board high resolution GPS mapping and navigation system, an EM31, an EM38 and a Seistronix seismic kit. The goal of the project is to observe and map unsaturated and saturated zone hydrological processes within soils and drift through repeated map- ping campaigns. The hydrogeophysics kit will be validated against a dense series of ground based observations of soil moisture deficit, suction and peizometric logging instruments. The Green Machine also includes a portable drilling and coring kit that can reach 10m in depth. Thus, the EM31 will attempt to map macroscale fluxes in the water table position, the EM38 will attempt to map the soil moisture deficit, and the seismic profile will show the depth of soil and drift. This 'go anywhere', rapid mapping facility will attempt to map hydrological processes in 4 dimensions in a non- intrusive and extensive manner. Whilst this paper will reflect only the experimental design and some early results, it is hoped that the Green Machine will play an active role in the future of hydrogeophysical research.

  16. Economic Decision Making Model for Geothermal Sludge Disposal alternatives (EDM-GSD): Version 1. 0

    SciTech Connect

    Not Available

    1987-09-01

    The Economic Decision Making Model for Geothermal Sludge Disposal Alternatives-Version 1.0'' (EDM-GSD 1.0) is a microcomputer-based dynamic model developed to assist in determining the benefits and costs of various geothermal solid waste treatment procedures. It is intended for use by geothermal managers in dealing with geothermal waste and treatment process issues as a means to assist in overcoming the technical and economic barriers to expanded geothermal energy utilization. The model is based on a 50MW flash plant. However, it is designed to provide the user with sufficient flexibility when inputing data to analyze all types of geothermal plants. Default values for economic and technical parameters can be overridden by the user through the input of specific data. In addition, data can be changed for any year of an analysis to account for desired changes in input parameters such as costs and distance to disposal sites. The results of the model will allow the user to: Determine current geothermal plant disposal costs; Evaluate the cost-effectiveness of alternative treatment techniques; and Evaluate the economic effects of changes in disposal regulations.

  17. Horizontal strain and precision of EDM from repeated surveys of the Precise Geodetic Net of Japan

    NASA Astrophysics Data System (ADS)

    Mizuno, Hiroo

    1994-09-01

    A simple statistical approach has been applied to the repeated electro-optical distance measurements (EDM) of 1,358 lines in the Tohoku district of Japan to obtain knowledge about the precision of EDM and the possible accumulation of strain. The average time interval between measurements is about seven or eight years. It is shown that the whole data of the difference between distance measurements repeated over a given line δD are interpreted in terms of EDM errors comprising distance proportional systematic errors and standard errors expressed by the usual formsqrt {α ^2 + β ^2 D^2 } . The rate of horizontal deformation must therefore be much smaller than the strain rates of about 0.7 ˜ 0.8 ppm over 7 to 8 years which have been hitherto expected.

  18. Search for Electric dipole moment (EDM) in laser cooled and trapped 225Ra atoms

    NASA Astrophysics Data System (ADS)

    Kalita, Mukut; Bailey, Kevin; Dietrich, Matthew; Green, John; Holt, Roy; Korsch, Wolfgang; Lu, Zheng-Tian; Lemke, Nathan; Mueller, Peter; O'Connor, Tom; Parker, Richard; Singh, Jaideep; Trimble, Will; Argonne National Laboratory Collaboration; University Of Chicago Collabration; University Of Kentucky Collaboration

    2014-05-01

    We are searching for an EDM of the diamagnetic 225Ra atom. 225Ra has nuclear spin I =1/2. Experimental sensitivity to its EDM is enhanced due to its heavy mass and the increased Schiff moment of its octupole deformed nucleus. Our experiment involves collecting laser cooled Ra atoms in a magneto-optical trap (MOT), transporting them 1 meter with a far off-resonant optical dipole trap (ODT) and then transferring the atoms to a second standing-wave ODT in our experimental chamber. We will report our recent experiences in polarizing and observing Larmor precession of 225Ra atoms in parallel electric and magnetic fields in a magnetically shielded region and progress towards a first measurement of the EDM of 225Ra. This work is supported by DOE, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357 and contract No. DE-FG02-99ER41101.

  19. Experimental search for EDM in diamagnetic atom 129Xe using active nuclear spin maser

    NASA Astrophysics Data System (ADS)

    Ichikawa, Yuichi; Sato, Tomoya; Ohtomo, Yuichi; Sakamoto, Yu; Kojima, Shuichiro; Funayama, Chikako; Hirao, Chika; Suzuki, Takahiro; Chikamori, Masatoshi; Hikota, Eri; Miyatake, Hirokazu; Nanao, Tsubasa; Suzuki, Kunifumi; Tsuchiya, Masato; Inoue, Takeshi; Furukawa, Takeshi; Yoshimi, Akihiko; Bidinosti, Christopher; Ino, Takashi; Ueno, Hideki; Matsuo, Yukari; Fukuyama, Takeshi; Asahi, Koichiro

    2014-09-01

    A permanent electric dipole moment (EDM) which directly means T-violation attracts much attention, because an unknown CP-violating phase which is necessary to understand the present matter-dominated Universe is expected to be probed by EDM. The present study aims at measuring the EDM in the diamagnetic atom 129Xe to a size of 10-28 ecm, stepping into a domain below the present upper limit by one order of magnitude. In the present experiment, we employ an active nuclear spin maser which has characteristics of the optical detection of the spin precession and the artificial production of the feedback field to sustain the spin precession over a long measurement duration. For the magnetometry in the measurement, a comagnetometer using 3He is incorporated to the spin maser system. In this presentation, the current status of our experiment will be given.

  20. Femtosecond laser ablation properties of transparent materials: impact of the laser process parameters on the machining throughput

    NASA Astrophysics Data System (ADS)

    Matylitsky, V. V.; Hendricks, F.; Aus der Au, J.

    2013-03-01

    High average power, high repetition rate femtosecond lasers with ?J pulse energies are increasingly used for bio-medical and material processing applications. With the introduction of femtosecond laser systems such as the SpiritTM platform developed by High Q Lasers and Spectra-Physics, micro-processing of solid targets with femtosecond laser pulses have obtained new perspectives for industrial applications [1]. The unique advantage of material processing with subpicosecond lasers is efficient, fast and localized energy deposition, which leads to high ablation efficiency and accuracy in nearly all kinds of solid materials. The study on the impact of the laser processing parameters on the removal rate for transparent substrate using femtosecond laser pulses will be presented. In particular, examples of micro-processing of poly-L-lactic acid (PLLA) - bio-degradable polyester and XensationTM glass (Schott) machined with SpiritTM ultrafast laser will be shown.

  1. Proceedings of the International Conference on Educational Data Mining (EDM) (2nd, Cordoba, Spain, July 1-3, 2009)

    ERIC Educational Resources Information Center

    Barnes, Tiffany, Ed.; Desmarais, Michel, Ed.; Romero, Cristobal, Ed.; Ventura, Sebastian, Ed.

    2009-01-01

    The Second International Conference on Educational Data Mining (EDM2009) was held at the University of Cordoba, Spain, on July 1-3, 2009. EDM brings together researchers from computer science, education, psychology, psychometrics, and statistics to analyze large data sets to answer educational research questions. The increase in instrumented…

  2. [Proceedings of the] International Conference on Educational Data Mining (EDM) (3rd, Pittsburgh, PA, July 11-13, 2010)

    ERIC Educational Resources Information Center

    Baker, Ryan S. J. d., Ed.; Merceron, Agathe, Ed.; Pavlik, Philip I., Jr., Ed.

    2010-01-01

    The Third International Conference on Data Mining (EDM 2010) was held in Pittsburgh, PA, USA. It follows the second conference at the University of Cordoba, Spain, on July 1-3, 2009 and the first edition of the conference held in Montreal in 2008, and a series of workshops within the AAAI, AIED, EC-TEL, ICALT, ITS, and UM conferences. EDM 2011…

  3. Proceedings of the International Conference on Educational Data Mining (EDM) (5th, Chania, Greece, June 19-21, 2012)

    ERIC Educational Resources Information Center

    International Educational Data Mining Society, 2012

    2012-01-01

    The 5th International Conference on Educational Data Mining (EDM 2012) is held in picturesque Chania on the beautiful Crete island in Greece, under the auspices of the International Educational Data Mining Society (IEDMS). The EDM 2012 conference is a leading international forum for high quality research that mines large data sets of educational…

  4. Automatic Inspection During Machining

    NASA Technical Reports Server (NTRS)

    Ransom, Clyde L.

    1988-01-01

    In experimental manufacturing process, numerically-controlled machine tool temporarily converts into inspection machine by installing electronic touch probes and specially-developed numerical-control software. Software drives probes in paths to and on newly machined parts and collects data on dimensions of parts.

  5. A novel diamond micro-/nano-machining process for the generation of hierarchical micro-/nano-structures

    NASA Astrophysics Data System (ADS)

    Zhu, Zhiwei; To, Suet; Ehmann, Kornel F.; Xiao, Gaobo; Zhu, Wule

    2016-03-01

    A new mechanical micro-/nano-machining process that combines rotary spatial vibrations (RSV) of a diamond tool and the servo motions of the workpiece is proposed and applied for the generation of multi-tier hierarchical micro-/nano-structures. In the proposed micro-/nano-machining system, the servo motion, as the primary cutting motion generated by a slow-tool-servo, is adopted for the fine generation of the primary surfaces with complex shapes. The RSV, as the tertiary cutting operation, is superimposed on the secondary fundamental rotary cutting motion to construct secondary nano-structures on the primary surface. Since the RSV system generally works at much higher frequencies and motion resolution than the primary and secondary motions, it leads to an inherent hierarchical cutting architecture. To investigate the machining performance, complex micro-/nano-structures were generated and explored by both numerical simulations and actual cutting tests. Rotary vibrations of the diamond tool at a constant rotational distance offer an inherent constant cutting velocity, leading to the ability for the generation of homogeneous micro-/nano-structures with fixed amplitudes and frequencies of the vibrations, even over large-scale surfaces. Furthermore, by deliberately combining the non-resonant three-axial vibrations and the servo motion, the generation of a variety of micro-/nano-structures with complex shapes and with flexibly tunable feature sizes can be achieved.

  6. PNPI differential EDM spectrometer and latest results of measurements of the neutron electric dipole moment

    NASA Astrophysics Data System (ADS)

    Serebrov, A. P.; Kolomenskiy, E. A.; Pirozhkov, A. N.; Krasnoshchekova, I. A.; Vasiliev, A. V.; Polyushkin, A. O.; Lasakov, M. S.; Murashkin, A. N.; Solovey, V. A.; Fomin, A. K.; Shoka, I. V.; Zherebtsov, O. M.; Alexandrov, E. B.; Dmitriev, S. P.; Dovator, N. A.; Geltenbort, P.; Ivanov, S. N.; Zimmer, O.

    2015-12-01

    In this work, the double chamber magnetic resonance spectrometer of the Petersburg Nuclear Physics Institute (PNPI) designed to measure the neutron electric dipole moment (EDM) is briefly described. A method for long storage of polarized ultracold neutrons in a resonance space with a superposed electric field collinear to the leading magnetic field is used. The results of the measurements carried out on the ILL reactor (Grenoble, France) are interpreted as the upper limit of the value of neutron EDM |dn| < 5.5 × 10-26 e cm at the 90% confidence level.

  7. Rb atomic magnetometer toward EDM experiment with laser cooled francium atoms

    NASA Astrophysics Data System (ADS)

    Inoue, Takeshi; Ando, Shun; Aoki, Takahiro; Arikawa, Hiroshi; Harada, Ken-Ichi; Hayamizu, Tomohiro; Ishikawa, Taisuke; Itoh, Masatoshi; Kato, Ko; Kawamura, Hirokazu; Sakamoto, Kosuke; Uchiyama, Aiko; Asahi, Koichiro; Yoshimi, Akihiro; Sakemi, Yasuhiro

    2014-09-01

    A permanent electric dipole moment (EDM) of a particle or an atom is a suited observable to test the physics beyond the standard model. We plan to search for the electron EDM by using the laser cooled francium (Fr) atom, since the Fr atom has a large enhancement factor of the electron EDM and the laser cooling techniques can suppress both statistical and systematic errors. In the EDM experiment, a fluctuation of the magnetic field is a main source of the errors. In order to achieve the high precision magnetometry, a magnetometer based on the nonlinear magneto-optical rotation effect of the Rb atom is under development. A long coherence time of Rb atom is the key issue for the highly sensitive detection of the field fluctuations. The coherence time is limited due both to collisions with an inner surface of a cell contained the Rb atom and to residual field in a magnetic shield. We prepared the cell coated with an anti-relaxation material and measured the relaxation time. A degauss of the shield was performed to eliminate the residual field. We will report the present status of the magnetometer. A permanent electric dipole moment (EDM) of a particle or an atom is a suited observable to test the physics beyond the standard model. We plan to search for the electron EDM by using the laser cooled francium (Fr) atom, since the Fr atom has a large enhancement factor of the electron EDM and the laser cooling techniques can suppress both statistical and systematic errors. In the EDM experiment, a fluctuation of the magnetic field is a main source of the errors. In order to achieve the high precision magnetometry, a magnetometer based on the nonlinear magneto-optical rotation effect of the Rb atom is under development. A long coherence time of Rb atom is the key issue for the highly sensitive detection of the field fluctuations. The coherence time is limited due both to collisions with an inner surface of a cell contained the Rb atom and to residual field in a magnetic shield. We prepared the cell coated with an anti-relaxation material and measured the relaxation time. A degauss of the shield was performed to eliminate the residual field. We will report the present status of the magnetometer. Supported by Grants-in-Aid for Scientic Research (Nos. 21104005 and 26220705).

  8. PNPI differential EDM spectrometer and latest results of measurements of the neutron electric dipole moment

    SciTech Connect

    Serebrov, A. P. Kolomenskiy, E. A.; Pirozhkov, A. N.; Krasnoshchekova, I. A.; Vasiliev, A. V.; Polyushkin, A. O.; Lasakov, M. S.; Murashkin, A. N.; Solovey, V. A.; Fomin, A. K.; Shoka, I. V.; Zherebtsov, O. M.; Alexandrov, E. B.; Dmitriev, S. P.; Dovator, N. A.; Geltenbort, P.; Ivanov, S. N.; Zimmer, O.

    2015-12-15

    In this work, the double chamber magnetic resonance spectrometer of the Petersburg Nuclear Physics Institute (PNPI) designed to measure the neutron electric dipole moment (EDM) is briefly described. A method for long storage of polarized ultracold neutrons in a resonance space with a superposed electric field collinear to the leading magnetic field is used. The results of the measurements carried out on the ILL reactor (Grenoble, France) are interpreted as the upper limit of the value of neutron EDM vertical bar d{sub n} vertical bar < 5.5 × 10{sup –26}e cm at the 90% confidence level.

  9. Recent Results and Progress on Leptonic and Storage Ring EDM Searches

    NASA Astrophysics Data System (ADS)

    Kawall, David

    2016-02-01

    The Standard Model is incomplete and unable to explain the matter-antimatter asymmetry in the universe. Many extensions of the Standard Model predict new particles and interactions with additional CP-violating phases that can explain this imbalance. Electric dipole moments (EDMs) of fundamental particles, which are generated by CP-violating interactions, can be enhanced by many orders of magnitude by contributions from this new physics to a magnitude within reach of current and planned experiments. New approaches to EDM searches using storage rings, and their sensitivity to new physics are presented.

  10. Interim results from the characterization testing of the Engineering Development (EDM) rubidium clocks for satellite applications

    NASA Technical Reports Server (NTRS)

    Powers, Edward D., Jr.; Danzy, Fredrick

    1990-01-01

    Some interim results from the environmental testing program to evaluate the Engineering Design Model (EDM) of the EG and G Spaceborne Rubidium Clock are presented. This effort is in support of the Global Positioning System (GPS) BLOCK IIR program and is intended to characterize the performance of EG and G design for BLOCK IIR satellite applications. Two EG and G EDM units are currently under test at NRL's Clock Test Facility to measure the long-term frequency stability, drift, and frequency versus temperature characteristics.

  11. Three-dimensional machining of carbon nanotube forests using water-assisted scanning electron microscope processing

    NASA Astrophysics Data System (ADS)

    Rajabifar, Bahram; Kim, Sanha; Slinker, Keith; Ehlert, Gregory J.; Hart, A. John; Maschmann, Matthew R.

    2015-10-01

    We demonstrate that vertically aligned carbon nanotubes (CNTs) can be precisely machined in a low pressure water vapor ambient using the electron beam of an environmental scanning electron microscope. The electron beam locally damages the irradiated regions of the CNT forest and also dissociates the water vapor molecules into reactive species including hydroxyl radicals. These species then locally oxidize the damaged region of the CNTs. The technique offers material removal capabilities ranging from selected CNTs to hundreds of cubic microns. We study how the material removal rate is influenced by the acceleration voltage, beam current, dwell time, operating pressure, and CNT orientation. Milled cuts with depths between 0-100 microns are generated, corresponding to a material removal rate of up to 20.1 μm3/min. The technique produces little carbon residue and does not disturb the native morphology of the CNT network. Finally, we demonstrate direct machining of pyramidal surfaces and re-entrant cuts to create freestanding geometries.

  12. Three-dimensional machining of carbon nanotube forests using water-assisted scanning electron microscope processing

    SciTech Connect

    Rajabifar, Bahram; Maschmann, Matthew R.; Kim, Sanha; Hart, A. John; Slinker, Keith; Ehlert, Gregory J.

    2015-10-05

    We demonstrate that vertically aligned carbon nanotubes (CNTs) can be precisely machined in a low pressure water vapor ambient using the electron beam of an environmental scanning electron microscope. The electron beam locally damages the irradiated regions of the CNT forest and also dissociates the water vapor molecules into reactive species including hydroxyl radicals. These species then locally oxidize the damaged region of the CNTs. The technique offers material removal capabilities ranging from selected CNTs to hundreds of cubic microns. We study how the material removal rate is influenced by the acceleration voltage, beam current, dwell time, operating pressure, and CNT orientation. Milled cuts with depths between 0–100 microns are generated, corresponding to a material removal rate of up to 20.1 μm{sup 3}/min. The technique produces little carbon residue and does not disturb the native morphology of the CNT network. Finally, we demonstrate direct machining of pyramidal surfaces and re-entrant cuts to create freestanding geometries.

  13. Machinability of Austempered Ductile Iron (ADI) Produced by Integrated Green Technology of Continuous Casting-Heat Treatment Processes

    SciTech Connect

    Meena, A.; El Mansori, M.; Ghidossi, P.

    2011-01-17

    This study presents the novel processing technique known as continuous casting-heat treatment processes to produce Austempered Ductile Iron (ADI) which is a new class of ductile iron. ADI is characterized by improved mechanical properties but has low machinability as compared to other cast irons and steel of similar strength. The novel technique is developed by the integration of casting (in die casting) and heat treatment processes in foundry to save cost energy and time. Specimens just after casting were austenitized at 930 deg. C for 90 min and then austempered in fluidized bed at 380 deg. C for 90 and 120 min. Hence, the effect of austempering time on the morphology of retained austenite and mechanical properties of the material were examined and compared with conventionally produced ADI. Drilling tests were then carried out to evaluate the machinability of ADI in terms of cutting forces, chip micro-hardness, chip morphology and surface roughness. The mechanical properties of ADI austempered for 120 min have found to be better as compare to the ADI austempered for 90 min.

  14. Machinability of Austempered Ductile Iron (ADI) Produced by Integrated Green Technology of Continuous Casting-Heat Treatment Processes

    NASA Astrophysics Data System (ADS)

    Meena, A.; El Mansori, M.; Ghidossi, P.

    2011-01-01

    This study presents the novel processing technique known as continuous casting-heat treatment processes to produce Austempered Ductile Iron (ADI) which is a new class of ductile iron. ADI is characterized by improved mechanical properties but has low machinability as compared to other cast irons and steel of similar strength. The novel technique is developed by the integration of casting (in die casting) and heat treatment processes in foundry to save cost energy and time. Specimens just after casting were austenitized at 930° C for 90 min and then austempered in fluidized bed at 380° C for 90 and 120 min. Hence, the effect of austempering time on the morphology of retained austenite and mechanical properties of the material were examined and compared with conventionally produced ADI. Drilling tests were then carried out to evaluate the machinability of ADI in terms of cutting forces, chip micro-hardness, chip morphology and surface roughness. The mechanical properties of ADI austempered for 120 min have found to be better as compare to the ADI austempered for 90 min.

  15. A Contact-Imaging Based Microfluidic Cytometer with Machine-Learning for Single-Frame Super-Resolution Processing

    PubMed Central

    Huang, Xiwei; Guo, Jinhong; Wang, Xiaolong; Yan, Mei; Kang, Yuejun; Yu, Hao

    2014-01-01

    Lensless microfluidic imaging with super-resolution processing has become a promising solution to miniaturize the conventional flow cytometer for point-of-care applications. The previous multi-frame super-resolution processing system can improve resolution but has limited cell flow rate and hence low throughput when capturing multiple subpixel-shifted cell images. This paper introduces a single-frame super-resolution processing with on-line machine-learning for contact images of cells. A corresponding contact-imaging based microfluidic cytometer prototype is demonstrated for cell recognition and counting. Compared with commercial flow cytometer, less than 8% error is observed for absolute number of microbeads; and 0.10 coefficient of variation is observed for cell-ratio of mixed RBC and HepG2 cells in solution. PMID:25111497

  16. A discrepancy within primate spatial vision and its bearing on the definition of edge detection processes in machine vision

    NASA Technical Reports Server (NTRS)

    Jobson, Daniel J.

    1990-01-01

    The visual perception of form information is considered to be based on the functioning of simple and complex neurons in the primate striate cortex. However, a review of the physiological data on these brain cells cannot be harmonized with either the perceptual spatial frequency performance of primates or the performance which is necessary for form perception in humans. This discrepancy together with recent interest in cortical-like and perceptual-like processing in image coding and machine vision prompted a series of image processing experiments intended to provide some definition of the selection of image operators. The experiments were aimed at determining operators which could be used to detect edges in a computational manner consistent with the visual perception of structure in images. Fundamental issues were the selection of size (peak spatial frequency) and circular versus oriented operators (or some combination). In a previous study, circular difference-of-Gaussian (DOG) operators, with peak spatial frequency responses at about 11 and 33 cyc/deg were found to capture the primary structural information in images. Here larger scale circular DOG operators were explored and led to severe loss of image structure and introduced spatial dislocations (due to blur) in structure which is not consistent with visual perception. Orientation sensitive operators (akin to one class of simple cortical neurons) introduced ambiguities of edge extent regardless of the scale of the operator. For machine vision schemes which are functionally similar to natural vision form perception, two circularly symmetric very high spatial frequency channels appear to be necessary and sufficient for a wide range of natural images. Such a machine vision scheme is most similar to the physiological performance of the primate lateral geniculate nucleus rather than the striate cortex.

  17. Electrochemical machining process for forming surface roughness elements on a gas turbine shroud

    DOEpatents

    Lee, Ching-Pang; Johnson, Robert Alan; Wei, Bin; Wang, Hsin-Pang

    2002-01-01

    The back side recessed cooling surface of a shroud defining in part the hot gas path of a turbine is electrochemically machined to provide surface roughness elements and spaces therebetween to increase the heat transfer coefficient. To accomplish this, an electrode with insulating dielectric portions and non-insulating portions is disposed in opposition to the cooling surface. By passing an electrolyte between the cooling surface and electrode and applying an electrical current between the electrode and a shroud, roughness elements and spaces therebetween are formed in the cooling surface in opposition to the insulating and non-insulating portions of the electrode, hence increasing the surface area and heat transfer coefficient of the shroud.

  18. Automated discrimination of dicentric and monocentric chromosomes by machine learning-based image processing.

    PubMed

    Li, Yanxin; Knoll, Joan H; Wilkins, Ruth C; Flegal, Farrah N; Rogan, Peter K

    2016-05-01

    Dose from radiation exposure can be estimated from dicentric chromosome (DC) frequencies in metaphase cells of peripheral blood lymphocytes. We automated DC detection by extracting features in Giemsa-stained metaphase chromosome images and classifying objects by machine learning (ML). DC detection involves (i) intensity thresholded segmentation of metaphase objects, (ii) chromosome separation by watershed transformation and elimination of inseparable chromosome clusters, fragments and staining debris using a morphological decision tree filter, (iii) determination of chromosome width and centreline, (iv) derivation of centromere candidates, and (v) distinction of DCs from monocentric chromosomes (MC) by ML. Centromere candidates are inferred from 14 image features input to a Support Vector Machine (SVM). Sixteen features derived from these candidates are then supplied to a Boosting classifier and a second SVM which determines whether a chromosome is either a DC or MC. The SVM was trained with 292 DCs and 3135 MCs, and then tested with cells exposed to either low (1 Gy) or high (2-4 Gy) radiation dose. Results were then compared with those of 3 experts. True positive rates (TPR) and positive predictive values (PPV) were determined for the tuning parameter, σ. At larger σ, PPV decreases and TPR increases. At high dose, for σ = 1.3, TPR = 0.52 and PPV = 0.83, while at σ = 1.6, the TPR = 0.65 and PPV = 0.72. At low dose and σ = 1.3, TPR = 0.67 and PPV = 0.26. The algorithm differentiates DCs from MCs, overlapped chromosomes and other objects with acceptable accuracy over a wide range of radiation exposures. Microsc. Res. Tech. 79:393-402, 2016. © 2016 Wiley Periodicals, Inc. PMID:26929213

  19. How fine-tuned is a large Muon EDM from Flavor?

    SciTech Connect

    Rueppell, Timo

    2010-02-10

    We study the possibility of having a large muon electric dipole moment (EDM) of the order 10{sup -24}-10{sup -22} ecm. We quantify how natural such a value is within the general minimal supersymmetric extension of the Standard Model with CP violation from lepton flavor violation.

  20. Development of Techniques for a Precision Neutron EDM Measurement at RCNP

    NASA Astrophysics Data System (ADS)

    Matsumiya, Ryohei; Masuda, Yasuhiro; Kawasaki, Shinsuke; Jeong, Sun-Chan; Watanabe, Yutaka; Hatanaka, Kichiji; Pierre, Edgard; Shin, Yunchang; Matsuta, Kensaku; Mihara, Mototsugu

    2014-09-01

    A non-zero neutron electric dipole moment (nEDM) breaks the time-reversal symmetry. A precision measurement of the nEDM is expected to be a good probe to search for theories beyond the standard model. We have been developing techniques for a nEDM measurement, using a high intensity ultra-cold neutron (UCN) source developed by the collaboration between KEK and RCNP. We have succeeded to polarize UCNs by a super conducting polarizer, and stored them in a cell. This cell will be installed in static magnetic and electric fields for a nEDM observation by the Ramsey separated-oscillatory-field magnetic resonance method. The homogeneity of the magnetic field is being improved aiming to increase the transverse relaxation time T2. A multilayered magnetic shielding and a compensation coil system was developed to cancel the geomagnetic field. Some materials around the cell which were not completely non-magnetic were replaced. We are developing a 129Xe co-magnetometer for the high precision field monitoring, and a high voltage system including electrodes with minimum UCN losses. In this talk, the present status of these apparatuses will be discussed.

  1. Geodetic monitoring of Mt. Vesuvius Volcano, Italy, based on EDM and GPS surveys

    NASA Astrophysics Data System (ADS)

    Pingue, Folco; Troise, Claudia; De Luca, Gaetano; Grassi, Vittorio; Scarpa, Roberto

    1998-06-01

    The geophysical monitoring system of Mt. Vesuvius volcano includes a geodetic EDM network having average basis lengths amounting to 6 km. This trilateration network is localised around the central crater and consists of 21 stations with a geometry allowing measurement of 60 slope distances. In order to relate this network to more stable areas and to other networks in the Apennines, the EDM net has been extended using GPS methods. In summer 1993 four GPS receivers (Leica System 200) were used on the same points measured with EDM method. During this survey two long bases from the volcano to the more stable limestone platform located in the S direction were measured. The same baselines were previously measured by using an AGA 600 laser geodimeter. In January 1995 a new survey was performed by using two infrared distantiometers (1 DISTOMAT DI3000 and an AGA 142). The comparison with the data since 1975 does not show any significant ground deformation to be ascribed to the volcanic activity. Moreover the consistency between GPS and EDM data allows to exclude systematic differences between these two methodologies for volcano monitoring.

  2. Development of a New Utm (universal Testing Machine) System for the Nano/micro In-Process Measurement

    NASA Astrophysics Data System (ADS)

    Kweon, Hyunkyu; Choi, Sungdae; Kim, Youngsik; Nam, Kiho

    Micro UTM (Universal Testing Machines) are becoming increasingly popular for testing the mechanical properties of MEMS materials, metal thin films, and micro-molecule materials1-2. And, new miniature testing machines that can perform in-process measurement in SEM, TEM, and SPM are also needed. In this paper, a new micro UTM with a precision positioning system that can be fine positioning stage. Coarse positioning is implemented by step motor. The size, load output and used in SEM, TEM, and SPM have been proposed. Bimorph type PZT precision actuator is used in displacement output of bimorph type UTM are 109×64×22(mm), about 35g, and 0.4 mm, respectively. And the displacement output is controlled in the block digital form. The results of the analysis and basic properties of positioning system and the UTM system are presented. In addition, the experiment results of in-process measurement during tensile load in SEM and AFM are showed.

  3. Machine processing of remotely sensed data; Proceedings of the Conference, Purdue University, West Lafayette, Ind., October 16-18, 1973

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Topics discussed include the management and processing of earth resources information, special-purpose processors for the machine processing of remotely sensed data, digital image registration by a mathematical programming technique, the use of remote-sensor data in land classification (in particular, the use of ERTS-1 multispectral scanning data), the use of remote-sensor data in geometrical transformations and mapping, earth resource measurement with the aid of ERTS-1 multispectral scanning data, the use of remote-sensor data in the classification of turbidity levels in coastal zones and in the identification of ecological anomalies, the problem of feature selection and the classification of objects in multispectral images, the estimation of proportions of certain categories of objects, and a number of special systems and techniques. Individual items are announced in this issue.

  4. Current breathomics--a review on data pre-processing techniques and machine learning in metabolomics breath analysis.

    PubMed

    Smolinska, A; Hauschild, A-Ch; Fijten, R R R; Dallinga, J W; Baumbach, J; van Schooten, F J

    2014-06-01

    We define breathomics as the metabolomics study of exhaled air. It is a strongly emerging metabolomics research field that mainly focuses on health-related volatile organic compounds (VOCs). Since the amount of these compounds varies with health status, breathomics holds great promise to deliver non-invasive diagnostic tools. Thus, the main aim of breathomics is to find patterns of VOCs related to abnormal (for instance inflammatory) metabolic processes occurring in the human body. Recently, analytical methods for measuring VOCs in exhaled air with high resolution and high throughput have been extensively developed. Yet, the application of machine learning methods for fingerprinting VOC profiles in the breathomics is still in its infancy. Therefore, in this paper, we describe the current state of the art in data pre-processing and multivariate analysis of breathomics data. We start with the detailed pre-processing pipelines for breathomics data obtained from gas-chromatography mass spectrometry and an ion-mobility spectrometer coupled to multi-capillary columns. The outcome of data pre-processing is a matrix containing the relative abundances of a set of VOCs for a group of patients under different conditions (e.g. disease stage, treatment). Independently of the utilized analytical method, the most important question, 'which VOCs are discriminatory?', remains the same. Answers can be given by several modern machine learning techniques (multivariate statistics) and, therefore, are the focus of this paper. We demonstrate the advantages as well the drawbacks of such techniques. We aim to help the community to understand how to profit from a particular method. In parallel, we hope to make the community aware of the existing data fusion methods, as yet unresearched in breathomics. PMID:24713999

  5. Triboplasma - the main component of plasma-chemical processes occurring in the friction units of machines and mechanisms in the presence of these drugs Tribo

    NASA Astrophysics Data System (ADS)

    Kashapov, N. F.; Sharifullin, S. N.

    2015-06-01

    In this paper, a technology capable of repairing worn surfaces of the friction units of machines and mechanisms. This technology can successfully be used in any production of engineering products. The proposed technology is low-cost, efficient and easy to use. It is shown that the processes occurring in the friction units of machines and mechanisms in the presence of these drugs tribo triboplasma plays a fundamental role, which arises in the contact mating surfaces.

  6. Annual Symposium on Machine Processing of Remotely Sensed Data, 4th, Purdue University, West Lafayette, Ind., June 21-23, 1977, Proceedings

    NASA Technical Reports Server (NTRS)

    Morrison, D. B. (Editor); Scherer, D. J.

    1977-01-01

    Papers are presented on a variety of techniques for the machine processing of remotely sensed data. Consideration is given to preprocessing methods such as the correction of Landsat data for the effects of haze, sun angle, and reflectance and to the maximum likelihood estimation of signature transformation algorithm. Several applications of machine processing to agriculture are identified. Various types of processing systems are discussed such as ground-data processing/support systems for sensor systems and the transfer of remotely sensed data to operational systems. The application of machine processing to hydrology, geology, and land-use mapping is outlined. Data analysis is considered with reference to several types of classification methods and systems.

  7. Non-traditional machining techniques

    SciTech Connect

    Day, Robert D; Fierro, Frank; Garcia, Felix P; Hatch, Douglass J; Randolph, Randall B; Reardon, Patrick T; Rivera, Gerald

    2008-01-01

    During the course of machining targets for various experiments it sometimes becomes necessary to adapt fixtures or machines, which are designed for one function, to another function. When adapting a machine or fixture is not adequate, it may be necessary to acquire a machine specifically designed to produce the component required. In addition to the above scenarios, the features of a component may dictate that multi-step machining processes are necessary to produce the component. This paper discusses the machining of four components where adaptation, specialized machine design, or multi-step processes were necessary to produce the components.

  8. Preliminary design and manufacturing feasibility study for a machined Zircaloy triangular pitch fuel rod support system (grids) (AWBA development program)

    SciTech Connect

    Horwood, W A

    1981-07-01

    General design features and manufacturing operations for a high precision machined Zircaloy fuel rod support grid intended for use in advanced light water prebreeder or breeder reactor designs are described. The grid system consists of a Zircaloy main body with fuel rod and guide tube cells machined using wire EDM, a separate AM-350 stainless steel insert spring which fits into a full length T-slot in each fuel rod cell, and a thin (0.025'' or 0.040'' thick) wire EDM machined Zircaloy coverplate laser welded to each side of the grid body to retain the insert springs. The fuel rods are placed in a triangular pitch array with a tight rod-to-rod spacing of 0.063 inch nominal. Two dimples are positioned at the mid-thickness of the grid (single level) with a 90/sup 0/ included angle. Data is provided on the effectiveness of the manufacturing operations chosen for grid machining and assembly.

  9. Architecture and data processing alternatives for Tse computer. Volume 1: Tse logic design concepts and the development of image processing machine architectures

    NASA Technical Reports Server (NTRS)

    Rickard, D. A.; Bodenheimer, R. E.

    1976-01-01

    Digital computer components which perform two dimensional array logic operations (Tse logic) on binary data arrays are described. The properties of Golay transforms which make them useful in image processing are reviewed, and several architectures for Golay transform processors are presented with emphasis on the skeletonizing algorithm. Conventional logic control units developed for the Golay transform processors are described. One is a unique microprogrammable control unit that uses a microprocessor to control the Tse computer. The remaining control units are based on programmable logic arrays. Performance criteria are established and utilized to compare the various Golay transform machines developed. A critique of Tse logic is presented, and recommendations for additional research are included.

  10. Graphical processing unit-based machine vision system for simultaneous measurement of shrinkage and soil release in fabrics

    NASA Astrophysics Data System (ADS)

    Kamalakannan, Sridharan; Gururajan, Arunkumar; Hill, Matthew; Shahriar, Muneem; Sari-Sarraf, Hamed; Hequet, Eric F.

    2010-04-01

    We present a machine vision system for simultaneous and objective evaluation of two important functional attributes of a fabric, namely, soil release and shrinkage. Soil release corresponds to the efficacy of the fabric in releasing stains after laundering and shrinkage essentially quantifies the dimensional changes in the fabric postlaundering. Within the framework of the proposed machine vision scheme, the samples are prepared using a prescribed procedure and subsequently digitized using a commercially available off-the-shelf scanner. Shrinkage measurements in the lengthwise and widthwise directions are obtained by detecting and measuring the distance between two pairs of appropriately placed markers. In addition, these shrinkage markers help in producing estimates of the location of the center of the stain on the fabric image. Using this information, a customized adaptive statistical snake is initialized, which evolves based on region statistics to segment the stain. Once the stain is localized, appropriate measurements can be extracted from the stain and the background image that can help in objectively quantifying stain release. In addition, the statistical snakes algorithm has been parallelized on a graphical processing unit, which allows for rapid evolution of multiple snakes. This, in turn, translates to the fact that multiple stains can be detected and segmented in a computationally efficient fashion. Finally, the aforementioned scheme is validated on a sizeable set of fabric images and the promising nature of the results help in establishing the efficacy of the proposed approach.

  11. Using state machines to model the Ion Torrent sequencing process and to improve read error rates

    PubMed Central

    Golan, David; Medvedev, Paul

    2013-01-01

    Motivation: The importance of fast and affordable DNA sequencing methods for current day life sciences, medicine and biotechnology is hard to overstate. A major player is Ion Torrent, a pyrosequencing-like technology which produces flowgrams sequences of incorporation values which are converted into nucleotide sequences by a base-calling algorithm. Because of its exploitation of ubiquitous semiconductor technology and innovation in chemistry, Ion Torrent has been gaining popularity since its debut in 2011. Despite the advantages, however, Ion Torrent read accuracy remains a significant concern. Results: We present FlowgramFixer, a new algorithm for converting flowgrams into reads. Our key observation is that the incorporation signals of neighboring flows, even after normalization and phase correction, carry considerable mutual information and are important in making the correct base-call. We therefore propose that base-calling of flowgrams should be done on a read-wide level, rather than one flow at a time. We show that this can be done in linear-time by combining a state machine with a Viterbi algorithm to find the nucleotide sequence that maximizes the likelihood of the observed flowgram. FlowgramFixer is applicable to any flowgram-based sequencing platform. We demonstrate FlowgramFixers superior performance on Ion Torrent Escherichia coli data, with a 4.8% improvement in the number of high-quality mapped reads and a 7.1% improvement in the number of uniquely mappable reads. Availability: Binaries and source code of FlowgramFixer are freely available at: http://www.cs.tau.ac.il/~davidgo5/flowgramfixer.html. Contact: davidgo5@post.tau.ac.il PMID:23813003

  12. Data Processing And Machine Learning Methods For Multi-Modal Operator State Classification Systems

    NASA Technical Reports Server (NTRS)

    Hearn, Tristan A.

    2015-01-01

    This document is intended as an introduction to a set of common signal processing learning methods that may be used in the software portion of a functional crew state monitoring system. This includes overviews of both the theory of the methods involved, as well as examples of implementation. Practical considerations are discussed for implementing modular, flexible, and scalable processing and classification software for a multi-modal, multi-channel monitoring system. Example source code is also given for all of the discussed processing and classification methods.

  13. 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.

  14. Computer-Aided TRIZ Ideality and Level of Invention Estimation Using Natural Language Processing and Machine Learning

    NASA Astrophysics Data System (ADS)

    Adams, Christopher; Tate, Derrick

    Patent textual descriptions provide a wealth of information that can be used to understand the underlying design approaches that result in the generation of novel and innovative technology. This article will discuss a new approach for estimating Degree of Ideality and Level of Invention metrics from the theory of inventive problem solving (TRIZ) using patent textual information. Patent text includes information that can be used to model both the functions performed by a design and the associated costs and problems that affect a design’s value. The motivation of this research is to use patent data with calculation of TRIZ metrics to help designers understand which combinations of system components and functions result in creative and innovative design solutions. This article will discuss in detail methods to estimate these TRIZ metrics using natural language processing and machine learning with the use of neural networks.

  15. Development of a cleaning process for uranium chips machined with a glycol-water-borax coolant

    SciTech Connect

    Taylor, P.A.

    1984-12-01

    A chip-cleaning process has been developed to remove the new glycol-water-borax coolant from oralloy chips. The process involves storing the freshly cut chips in Freon-TDF until they are cleaned, washing with water, and displacing the water with Freon-TDF. The wash water can be reused many times and still yield clean chips and then be added to the coolant to make up for evaporative losses. The Freon-TDF will be cycled by evaporation. The cleaning facility is currently being designed and should be operational by April 1985.

  16. The Supraspliceosome — A Multi-Task Machine for Regulated Pre-mRNA Processing in the Cell Nucleus

    PubMed Central

    Shefer, Kinneret; Sperling, Joseph; Sperling, Ruth

    2014-01-01

    Pre-mRNA splicing of Pol II transcripts is executed in the mammalian cell nucleus within a huge (21 MDa) and highly dynamic RNP machine — the supraspliceosome. It is composed of four splicing active native spliceosomes, each resembling an in vitro assembled spliceosome, which are connected by the pre-mRNA. Supraspliceosomes harbor protein splicing factors and all the five-spliceosomal U snRNPs. Recent analysis of specific supraspliceosomes at defined splicing stages revealed that they harbor all five spliceosomal U snRNAs at all splicing stages. Supraspliceosomes harbor additional pre-mRNA processing components, such as the 5′-end and 3′-end processing components, and the RNA editing enzymes ADAR1 and ADAR2. The structure of the native spliceosome, at a resolution of 20 Å, was determined by cryo-EM. A unique spatial arrangement of the spliceosomal U snRNPs within the native spliceosome emerged from in-silico studies, localizing the five U snRNPs mostly within its large subunit, and sheltering the active core components deep within the spliceosomal cavity. The supraspliceosome provides a platform for coordinating the numerous processing steps that the pre-mRNA undergoes: 5′ and 3′-end processing activities, RNA editing, constitutive and alternative splicing, and processing of intronic microRNAs. It also harbors a quality control mechanism termed suppression of splicing (SOS) that, under normal growth conditions, suppresses splicing at abundant intronic latent 5′ splice sites in a reading frame-dependent fashion. Notably, changes in these regulatory processing activities are associated with human disease and cancer. These findings emphasize the supraspliceosome as a multi-task master regulator of pre-mRNA processing in the cell nucleus. PMID:25408845

  17. Characterization of a gene from the EDM1-PSACH region of human chromosome 19p

    SciTech Connect

    Lennon, G.G.; Giorgi, D.; Martin, J.R.

    1994-09-01

    Genetic linkage mapping has indicated that both multiple epiphyseal dysplasia (EDM1), a dominantly inherited chondrodysplasia, and pseudoachondroplasia (PSACH), a skeletal disorder associated with dwarfism, map to a 2-3 Mb region of human chromosome 19p. We have isolated a partial cDNA from this region using hybrid selection, and report on progress towards the characterization of the genomic structure and transcription of the corresponding gene. Sequence analysis of the cDNA to date indicates that this gene is likely to be expressed within extracellular matrix tissues. Defects in this gene or neighboring gene family members may therefore lead to EDM1, PSACH, or other connective tissue and skeletal disorders.

  18. CATSI EDM: recent advances in the development and validation of a ruggedized passive standoff CWA sensor

    NASA Astrophysics Data System (ADS)

    Lavoie, Hugo; Thériault, Jean-Marc; Bouffard, François; Puckrin, Eldon; Turcotte, Caroline S.; Lacasse, Paul

    2008-04-01

    Defence Research and Development Canada (DRDC) - Valcartier is currently developing a ruggedized passive standoff sensor for the detection of chemical warfare agents (CWAs) based on differential Fourier-transform infrared (FTIR) radiometry. This system is referred to as the Compact ATmospheric Sounding Interferometer (CATSI) Engineering Development Model (EDM). The CATSI EDM sensor is based on the use of a double-beam FTIR spectrometer that is optimized for optical subtraction. A description of the customized sensor is given along with a discussion on the detection and identification approaches that have been developed. Preliminary results of validation from a number of laboratory measurements and open-air trials are analyzed to establish the capability of detection and identification of various toxic and non-toxic chemical vapor plumes. These results clearly demonstrate the capability of the passive differential radiometric approach for the standoff detection and identification of chemical vapors at distances up to a few kilometers from the sensor.

  19. Lepton Flavour Violation and electron EDM in SUSY with a non-abelian flavour symmetry

    SciTech Connect

    Calibbi, Lorenzo

    2008-11-23

    We present the lepton sector phenomenology of a supersymmetric flavour model based on a SU(3) horizontal symmetry. This model successfully reproduces the observed fermion masses and mixings, without introducing unacceptably large SUSY sources of flavour and CP violation. We show that the model, which is at present weakly constrained, predicts the electron EDM and {mu}{yields}e,y to be within the final sensitivity of the currently running experiments, at least for SUSY masses within the reach of the LHC.

  20. Nuclear Spin Maser at Highly Stabilized Low Magnetic Field and Search for Atomic EDM

    SciTech Connect

    Yoshimi, A.; Asahi, K.; Inoue, T.; Uchida, M.; Hatakeyama, N.; Tsuchiya, M.; Kagami, S.

    2009-08-04

    A nuclear spin maser is operated at a low static field through an active feedback scheme based on an optical nuclear spin detection and succeeding spin control by a transverse field application. The frequency stability of this optical-coupling spin maser is improved by installation of a low-noise current source for a solenoid magnet producing a static magnetic field in the maser operation. Experimental devices for application of the maser to EDM experiment are being developed.

  1. Analytical Model for Chip Formation in Case of Orthogonal Machining Process

    NASA Astrophysics Data System (ADS)

    Salvatore, Ferdinando; Mabrouki, Tarek; Hamdi, Hédi

    2011-01-01

    The present work deals with the presentation of analytical methodology allowing the modelling of chip formation. For that a "decomposition approach", based on assuming that the material removal is the summation of two contributions: ploughing and pure cut was adopted. Moreover, this analytical model was calibrated by a finite element model and experimental data in terms of temperature and forces evolutions. The global aim is to propose to the industrial community, an efficient rapid-execution analytical model concerning the material removal in the case of an orthogonal cutting process.

  2. Digital signal processing control of induction machine`s torque and stator flux utilizing the direct stator flux field orientation method

    SciTech Connect

    Seiz, J.B.

    1997-04-01

    This paper presents a review of the Direct Stator Flux Field Orientation control method. This method can be used to control an induction motor`s torque and flux directly and is the application of interest for this thesis. This control method is implemented without the traditional feedback loops and associated hardware. Predictions are made, by mathematical calculations, of the stator voltage vector. The voltage vector is determined twice a switching period. The switching period is fixed throughout the analysis. The three phase inverter duty cycle necessary to control the torque and flux of the induction machine is determined by the voltage space vector Pulse Width Modulation (PWM) technique. Transient performance of either the flux or torque requires an alternate modulation scheme which is also addressed in this thesis. A block diagram of this closed loop system is provided. 22 figs., 7 tabs.

  3. Challenges and opportunities in the search for electric dipole moment (EDM) in 225Ra atom

    NASA Astrophysics Data System (ADS)

    Kalita, Mukut; Bailey, Kevin; Dietrich, Matthew; Greene, John; Holt, Roy; Korsch, Wolfgang; Lu, Zheng-Tian; Mueller, Peter; O'Connor, Thomas; Parker, Richard; Sulai, Ibrahim; Singh, Jaideep

    2011-10-01

    The observation of a permanent electric dipole moment (EDM) in a non-degenerate system would indicate violation of time reversal symmetry. 225Ra atom is a particularly attractive candidate for this search since it has a nuclear spin I = 1/2 and has a significant nuclear octupole deformation. This property increases the Schiff moment of the nucleus and therefore enhances the atomic EDM. The half life (t1/2 = 14.9 days) of 225Ra is sufficiently long to perform EDM searches. Our group has already demonstrated the trapping of laser cooled Ra atoms in a magneto-optical trap (MOT) and transferring them to a far off resonant optical dipole trap (ODT). We will discuss our recent progress on manipulation of ultra cold Ra atoms in the ODT, efforts in improving our laser systems and generation of electric and magnetic fields required for the measurement. This work is supported by DOE, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357 and contract No. DE-FG02-99ER41101.

  4. Sensitivity Reach of the Neutron EDM Experiment: The Electric Field Strength

    NASA Astrophysics Data System (ADS)

    Hennings-Yeomans, R.; Cooper, M.; Currie, S. A.; Makela, M. F.; Ramsey, J. C.; Tajima, S.; Womack, T. L.; Long, J. C.; Stanislaus, S.

    2010-08-01

    The search for an electric dipole moment of the neutron tests physics beyond the Standard Model such as new sources of CP-violation and Supersymmetry. The nEDM experiment aims to improve the sensitivity on the current limit of the electric dipole moment of the neutron to <10-27 eṡcm. The experiment will use a flux of Ultra Cold Neutrons (UCNs) produced and stored in a bath of superfluid He-II. A change in precession frequency is expected for a non-zero EDM when an electric field is applied parallel and antiparallel to a magnetic field across the neutron storage cell. A dominant parameter in terms of reducing the statistical uncertainty of this measurement is the strength of the applied electric field. An experiment to measure if superfluid He-II can sustain up to 50 kV/cm for a volume and electrode spacings comparable to the nEDM experiment has been constructed at Los Alamos National Laboratory. It consists in a large-area parallel plate capacitor immersed in a 200 liter central volume inside a suitable cryostat that in turn is connected to a dilution refrigerator unit. A description of test runs and the status of the experiment is presented.

  5. New Results from a Search for the Electric Dipole Moment (EDM) of 99Hg

    NASA Astrophysics Data System (ADS)

    Heckel, Blayne

    2015-05-01

    The measurement of a nonzero EDM of an atom or elementary particle, at current levels of experimental sensitivity, would imply CP violation beyond the CKM matrix of the Standard Model. Additional sources of CP violation have been proposed to help explain the matter-antimatter asymmetry observed in our universe and the magnitude of ΘQCD, the strength of CP-violation in the strong interaction, remains unknown. We have recently completed a set of measurements on the EDM of 199Hg, sensitive to both new sources of CP violation and ΘQCD.The experiment compares the phase accumulated by precessing Hg atom spins in vapor cells with electric fields parallel and anti-parallel to a common magnetic field. The statistical sensitivity of new measurements represents a factor of 3 to 4 improvement over previous results. A description of the EDM experiment and the data, along with the current state of the systematic error analysis, will be presented. This work was supported by NSF Grant PHY-1306743 and by the U.S. Department of Energy Office of Science, Office of Nuclear Physics under Award Number DE-FG02-97ER41020.

  6. Sensitivity Reach of the Neutron EDM Experiment: The Electric Field Strength

    SciTech Connect

    Hennings-Yeomans, R.; Cooper, M.; Currie, S. A.; Makela, M. F.; Ramsey, J. C.; Tajima, S.; Womack, T. L.; Long, J. C.; Stanislaus, S.

    2010-08-04

    The search for an electric dipole moment of the neutron tests physics beyond the Standard Model such as new sources of CP-violation and Supersymmetry. The nEDM experiment aims to improve the sensitivity on the current limit of the electric dipole moment of the neutron to <10{sup -27} e{center_dot}cm. The experiment will use a flux of Ultra Cold Neutrons (UCNs) produced and stored in a bath of superfluid He-II. A change in precession frequency is expected for a non-zero EDM when an electric field is applied parallel and antiparallel to a magnetic field across the neutron storage cell. A dominant parameter in terms of reducing the statistical uncertainty of this measurement is the strength of the applied electric field. An experiment to measure if superfluid He-II can sustain up to 50 kV/cm for a volume and electrode spacings comparable to the nEDM experiment has been constructed at Los Alamos National Laboratory. It consists in a large-area parallel plate capacitor immersed in a 200 liter central volume inside a suitable cryostat that in turn is connected to a dilution refrigerator unit. A description of test runs and the status of the experiment is presented.

  7. Advanced measurement and analysis of surface textures produced by micro-machining processes

    NASA Astrophysics Data System (ADS)

    Bordatchev, Evgueni V.; Hafiz, Abdullah M. K.

    2014-09-01

    Surface texture of a part or a product has significant effects on its functionality, physical-mechanical properties and visual appearance. In particular for miniature products, the implication of surface quality becomes critical owing to the presence of geometrical features with micro/nano-scale dimensions. Qualitative and quantitative assessments of surface texture are carried out predominantly by profile parameters, which are often insufficient to address the contribution of constituent spatial components with varied amplitudes and wavelengths. In this context, this article presents a novel approach for advanced measurement and analysis of profile average roughness (Ra) and its spatial distribution at different wavelength intervals. The applicability of the proposed approach was verified for three different surface topographies prepared by grinding, laser micro-polishing and micro-milling processes. From the measurement and analysis results, Ra(λ) spatial distribution was found to be an effective measure of revealing the contributions of various spatial components within specific wavelength intervals towards formation of the entire surface profile. In addition, the approach was extended to the measurement and analysis of areal average roughness Sa(λ) spatial distribution within different wavelength intervals. Besides, the proposed method was demonstrated to be a useful technique in developing a functional correlation between a manufacturing process and its corresponding surface profile.

  8. Technique for Machining Glass

    NASA Technical Reports Server (NTRS)

    Rice, S. H.

    1982-01-01

    Process for machining glass with conventional carbide tools requires a small quantity of a lubricant for aluminum applied to area of glass to be machined. A carbide tool is then placed against workpiece with light pressure. Tool is raised periodically to clear work of glass dust and particles. Additional lubricant is applied as it is displaced.

  9. Machining heavy plastic sections

    NASA Technical Reports Server (NTRS)

    Stalkup, O. M.

    1967-01-01

    Machining technique produces consistently satisfactory plane-parallel optical surfaces for pressure windows, made of plexiglass, required to support a photographic study of liquid rocket combustion processes. The surfaces are machined and polished to the required tolerances and show no degradation from stress relaxation over periods as long as 6 months.

  10. Monte Carlo point process estimation of electromyographic envelopes from motor cortical spikes for brain-machine interfaces

    NASA Astrophysics Data System (ADS)

    Liao, Yuxi; She, Xiwei; Wang, Yiwen; Zhang, Shaomin; Zhang, Qiaosheng; Zheng, Xiaoxiang; Principe, Jose C.

    2015-12-01

    Objective. Representation of movement in the motor cortex (M1) has been widely studied in brain-machine interfaces (BMIs). The electromyogram (EMG) has greater bandwidth than the conventional kinematic variables (such as position, velocity), and is functionally related to the discharge of cortical neurons. As the stochastic information of EMG is derived from the explicit spike time structure, point process (PP) methods will be a good solution for decoding EMG directly from neural spike trains. Previous studies usually assume linear or exponential tuning curves between neural firing and EMG, which may not be true. Approach. In our analysis, we estimate the tuning curves in a data-driven way and find both the traditional functional-excitatory and functional-inhibitory neurons, which are widely found across a rat’s motor cortex. To accurately decode EMG envelopes from M1 neural spike trains, the Monte Carlo point process (MCPP) method is implemented based on such nonlinear tuning properties. Main results. Better reconstruction of EMG signals is shown on baseline and extreme high peaks, as our method can better preserve the nonlinearity of the neural tuning during decoding. The MCPP improves the prediction accuracy (the normalized mean squared error) 57% and 66% on average compared with the adaptive point process filter using linear and exponential tuning curves respectively, for all 112 data segments across six rats. Compared to a Wiener filter using spike rates with an optimal window size of 50 ms, MCPP decoding EMG from a point process improves the normalized mean square error (NMSE) by 59% on average. Significance. These results suggest that neural tuning is constantly changing during task execution and therefore, the use of spike timing methodologies and estimation of appropriate tuning curves needs to be undertaken for better EMG decoding in motor BMIs.

  11. Viral capsid assembly as a model for protein aggregation diseases: Active processes catalyzed by cellular assembly machines comprising novel drug targets.

    PubMed

    Marreiros, Rita; Müller-Schiffmann, Andreas; Bader, Verian; Selvarajah, Suganya; Dey, Debendranath; Lingappa, Vishwanath R; Korth, Carsten

    2015-09-01

    Viruses can be conceptualized as self-replicating multiprotein assemblies, containing coding nucleic acids. Viruses have evolved to exploit host cellular components including enzymes to ensure their replicative life cycle. New findings indicate that also viral capsid proteins recruit host factors to accelerate their assembly. These assembly machines are RNA-containing multiprotein complexes whose composition is governed by allosteric sites. In the event of viral infection, the assembly machines are recruited to support the virus over the host and are modified to achieve that goal. Stress granules and processing bodies may represent collections of such assembly machines, readily visible by microscopy but biochemically labile and difficult to isolate by fractionation. We hypothesize that the assembly of protein multimers such as encountered in neurodegenerative or other protein conformational diseases, is also catalyzed by assembly machines. In the case of viral infection, the assembly machines have been modified by the virus to meet the virus' need for rapid capsid assembly rather than host homeostasis. In the case of the neurodegenerative diseases, it is the monomers and/or low n oligomers of the so-called aggregated proteins that are substrates of assembly machines. Examples for substrates are amyloid β peptide (Aβ) and tau in Alzheimer's disease, α-synuclein in Parkinson's disease, prions in the prion diseases, Disrupted-in-schizophrenia 1 (DISC1) in subsets of chronic mental illnesses, and others. A likely continuum between virus capsid assembly and cell-to-cell transmissibility of aggregated proteins is remarkable. Protein aggregation diseases may represent dysfunction and dysregulation of these assembly machines analogous to the aberrations induced by viral infection in which cellular homeostasis is pathologically reprogrammed. In this view, as for viral infection, reset of assembly machines to normal homeostasis should be the goal of protein aggregation therapeutics. A key basis for the commonality between viral and neurodegenerative disease aggregation is a broader definition of assembly as more than just simple aggregation, particularly suited for the crowded cytoplasm. The assembly machines are collections of proteins that catalytically accelerate an assembly reaction that would occur spontaneously but too slowly to be relevant in vivo. Being an enzyme complex with a functional allosteric site, appropriated for a non-physiological purpose (e.g. viral infection or conformational disease), these assembly machines present a superior pharmacological target because inhibition of their active site will amplify an effect on their substrate reaction. Here, we present this hypothesis based on recent proof-of-principle studies against Aβ assembly relevant in Alzheimer's disease. PMID:25451064

  12. Decoding Semi-Constrained Brain Activity from fMRI Using Support Vector Machines and Gaussian Processes

    PubMed Central

    Wehenkel, Louis; Maquet, Pierre; Phillips, Christophe

    2012-01-01

    Predicting a particular cognitive state from a specific pattern of fMRI voxel values is still a methodological challenge. Decoding brain activity is usually performed in highly controlled experimental paradigms characterized by a series of distinct states induced by a temporally constrained experimental design. In more realistic conditions, the number, sequence and duration of mental states are unpredictably generated by the individual, resulting in complex and imbalanced fMRI data sets. This study tests the classification of brain activity, acquired on 16 volunteers using fMRI, during mental imagery, a condition in which the number and duration of mental events were not externally imposed but self-generated. To deal with these issues, two classification techniques were considered (Support Vector Machines, SVM, and Gaussian Processes, GP), as well as different feature extraction methods (General Linear Model, GLM and SVM). These techniques were combined in order to identify the procedures leading to the highest accuracy measures. Our results showed that 12 data sets out of 16 could be significantly modeled by either SVM or GP. Model accuracies tended to be related to the degree of imbalance between classes and to task performance of the volunteers. We also conclude that the GP technique tends to be more robust than SVM to model unbalanced data sets. PMID:22563410

  13. An innovative method for coordinate measuring machine one-dimensional self-calibration with simplified experimental process.

    PubMed

    Fang, Cheng; Butler, David Lee

    2013-05-01

    In this paper, an innovative method for CMM (Coordinate Measuring Machine) self-calibration is proposed. In contrast to conventional CMM calibration that relies heavily on a high precision reference standard such as a laser interferometer, the proposed calibration method is based on a low-cost artefact which is fabricated with commercially available precision ball bearings. By optimizing the mathematical model and rearranging the data sampling positions, the experimental process and data analysis can be simplified. In mathematical expression, the samples can be minimized by eliminating the redundant equations among those configured by the experimental data array. The section lengths of the artefact are measured at arranged positions, with which an equation set can be configured to determine the measurement errors at the corresponding positions. With the proposed method, the equation set is short of one equation, which can be supplemented by either measuring the total length of the artefact with a higher-precision CMM or calibrating the single point error at the extreme position with a laser interferometer. In this paper, the latter is selected. With spline interpolation, the error compensation curve can be determined. To verify the proposed method, a simple calibration system was set up on a commercial CMM. Experimental results showed that with the error compensation curve uncertainty of the measurement can be reduced to 50%. PMID:23742585

  14. Machine tools get smarter

    SciTech Connect

    Valenti, M.

    1995-11-01

    This article describes how, using software, sensors, and controllers, a new generation of intelligent machine tools are optimizing grinding, milling, and molding processes. A paradox of manufacturing parts is that the faster the parts are made, the less accurate they are--and vice versa. However, a combination of software, sensors, controllers, and mechanical innovations are being used to create a new generation of intelligent machine tools capable of optimizing their own grinding, milling, and molding processes. These brainy tools are allowing manufacturers to machine more-complex, higher-quality parts in shorter cycle times. The technology also lowers scrap rates and reduces or eliminates the need for polishing inadequately finished parts.

  15. Processing and Characterization of Novel Biomimetic Nanoporous Bioceramic Surface on β-Ti Implant by Powder Mixed Electric Discharge Machining

    NASA Astrophysics Data System (ADS)

    Prakash, Chander; Kansal, H. K.; Pabla, B. S.; Puri, Sanjeev

    2015-09-01

    Herein, a β-Ti-based implant was subjected to powder mixed electric discharge machining (PMEDM) for surface modification to produce a novel biomimetic nanoporous bioceramic surface. The microstructure, surface topography, and phase composition of the non-machined and machined (PMEDMed) surfaces were investigated using field-emission scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffraction. The microhardness of the surfaces was measured on a Vickers hardness tester. The corrosion resistance of the surfaces was evaluated via potentiodynamic polarization measurements in simulated body fluid. The application of PMEDM not only altered the surface chemistry, but also imparted the surface with a nanoporous topography or a natural bone-like surface structure. The characterization results confirmed that the alloyed layer mainly comprised bioceramic oxides and carbide phases (TiO2, Nb2O5, ZrO2, SiO2, TiC, NbC, SiC). The microhardness of PMEDMed surface was twofold higher than that of the base material (β-Ti alloy), primarily because of the formation of the hard carbide phases on the machined layer. Electrochemical analysis revealed that PMEDMed surface featured insulative and protective properties and thus displayed higher corrosion resistance ability when compared with the non-machined surface. This result was attributed to the formation of the bioceramic oxides on the machined surface. Additionally, the in vitro biocompatibility of the surfaces was evaluated using human osteoblastic cell line MG-63. PMEDMed surface with a micro-, sub-micro-, and nano-structured topography exhibited bioactivity and improved biocompatibility relative to β-Ti surface. Furthermore, PMEDMed surface enabled better adhesion and growth of MG-63 when compared with the non-machined substrate.

  16. Search for an Atomic EDM with Optical-Coupling Nuclear Spin Oscillator

    SciTech Connect

    Asahi, K.; Uchida, M.; Inoue, T.; Hatakeyama, N.; Yoshimi, A.

    2007-06-13

    We have constructed a nuclear spin oscillator of a new type, that employs a feedback scheme based on an optical spin detection and suceeding spin control by a transverse field application. This spin oscillator parallels the conventional spin maser in many points, but exhibits advantages and requirements that are different from those with the spin maser. By means of the optical-coupling nuclear spin oscillator, an experimental setup to search for an electric dipole moment (EDM) in a spin 1/2 diamagnetic atom 129Xe is being developed.

  17. 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.

  18. Electric breakdown and ionization detection in normal liquid and superfluid 4He for the SNA nEDM experiment

    NASA Astrophysics Data System (ADS)

    Karcz, Maciej

    A new experiment to search for the neutron electric dipole moment (nEDM) is under construction at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. The SNS nEDM experiment is a national collaboration spanning over 20 universities and laboratories with more than 100 physicists and engineers contributing to the research and development. The search for a nEDM is a precision test of time reversal symmetry in particle physics, in the absence of a discovery, the SNS nEDM experiment seeks to improve the present limit on the nEDM value by two orders of magnitude. A non-zero value of the nEDM would help to explain the asym- metry between matter and anti-matter in the universe by providing an additional source of charge conjugation and parity symmetry violation, a necessary ingredient in the theory of baryogenesis in the early universe. The nEDM experiment will measure the Larmor precession frequency of neutrons by detecting scintillation from neutron capture by a dilute concentration of 3He inside a bath of superfluid 4He. Neutron capture by 3He is spin-dependent and the magnetic moments of the neutron and the 3He nucleus are comparable. A direct measurement of the precession frequency of polarized 3He and scintillation from neutron capture allows for the relative precession frequencies of 3He and the neutron to be determined. The experiment will then look for changes in the relative precession of 3He and neutrons under the influence of strong electric fields. 3He has negligible EDM and therefore any deviation due to an applied electric field would be from a nEDM. The nEDM experiment will need to apply strong electric fields inside superfluid (SF) 4He and it was necessary to investigate the ability of SF 4He to sustain electric fields. An experiment to study electric breakdown in superfluid 4He was constructed at the Indiana University Center for Exploration of Energy and Matter (CEEM). The experiment studied the electric breakdown behavior of liquid Helium throughout the pressure-temperature phase space, between 1 bar and the saturation curve and between 4.2 K and 1.7 K. A new breakdown hysteresis in liquid helium was discovered and is attributed to the suppression of heterogeneous nucleation sites inside the liquid. A phenomenological model involving the Townsend breakdown mechanism and Paschen's Law in liquid helium is proposed. In addition, the many challenges faced by efficient scintillation detection in the cryogenic environment of the nEDM experiment motivated additional studies at CEEM. To test the effect of an electric field on scintillation in superfluid, a SF test cell was constructed inside a dilution refrigerator and it was found that the scintil- lation intensity from a 241Am source in the cell, is reduced at high electric fields. Alternatives to scintillation detection for the nEDM experiment were also explored and the test cell was reconfigured to operate as a superfluid ionization chamber. The superfluid ionization chamber was tested with 241Am in pulse mode and current mode configurations. While the pulse mode in superfluid, which relies on the drift velocity of charges, is hindered by quasi-particle excitations in superfluid, results of current mode measurements appear promising. To further explore the prospect of cryogenic ionization detection, a detector cryo-stat capable of detecting neutrons using a 10B converter was also constructed at CEEM and tested at the Indiana University Low Energy Neutron Source (LENS). The neutron detector cryostat has the benefit of being able to modulate the ioniza- tion source which was not possible with the superfluid ionization chamber. Tests with argon gas led to the development of more efficient boron targets. The cryogenic test of ionization detection in current mode will be discussed.

  19. Advanced balancing using laser machining

    NASA Astrophysics Data System (ADS)

    Walton, J. F.; Cronin, M.; Mehta, Ramesh

    1991-09-01

    A laser-balancing system is described, and materials machined with the system are examined by means of fatigue testing and comparisons with as-machined components. An Nd:YAG laser is used in the automated system to machine rotating components, and the components are examined to study the effects of the laser material-removal process. Materials from turbine engines are handground, machined, or laser-machined, and fatigue testing is used in conjunction with SEM to study the effects on material fatigue life. Laser machining is shown to degrade the fatigue life more than handgrinding, but the material-removal process does not reduce the life of a tested shaft component. It is suggested that fatigue tests of transverse laser machining be conducted to assess possible techniques for refining the laser removal process.

  20. Electric machine

    DOEpatents

    El-Refaie, Ayman Mohamed Fawzi; Reddy, Patel Bhageerath

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  1. A Telesurveillance System With Automatic Electrocardiogram Interpretation Based on Support Vector Machine and Rule-Based Processing

    PubMed Central

    Lin, Ching-Miao; Lai, Feipei; Ho, Yi-Lwun; Hung, Chi-Sheng

    2015-01-01

    Background Telehealth care is a global trend affecting clinical practice around the world. To mitigate the workload of health professionals and provide ubiquitous health care, a comprehensive surveillance system with value-added services based on information technologies must be established. Objective We conducted this study to describe our proposed telesurveillance system designed for monitoring and classifying electrocardiogram (ECG) signals and to evaluate the performance of ECG classification. Methods We established a telesurveillance system with an automatic ECG interpretation mechanism. The system included: (1) automatic ECG signal transmission via telecommunication, (2) ECG signal processing, including noise elimination, peak estimation, and feature extraction, (3) automatic ECG interpretation based on the support vector machine (SVM) classifier and rule-based processing, and (4) display of ECG signals and their analyzed results. We analyzed 213,420 ECG signals that were diagnosed by cardiologists as the gold standard to verify the classification performance. Results In the clinical ECG database from the Telehealth Center of the National Taiwan University Hospital (NTUH), the experimental results showed that the ECG classifier yielded a specificity value of 96.66% for normal rhythm detection, a sensitivity value of 98.50% for disease recognition, and an accuracy value of 81.17% for noise detection. For the detection performance of specific diseases, the recognition model mainly generated sensitivity values of 92.70% for atrial fibrillation, 89.10% for pacemaker rhythm, 88.60% for atrial premature contraction, 72.98% for T-wave inversion, 62.21% for atrial flutter, and 62.57% for first-degree atrioventricular block. Conclusions Through connected telehealth care devices, the telesurveillance system, and the automatic ECG interpretation system, this mechanism was intentionally designed for continuous decision-making support and is reliable enough to reduce the need for face-to-face diagnosis. With this value-added service, the system could widely assist physicians and other health professionals with decision making in clinical practice. The system will be very helpful for the patient who suffers from cardiac disease, but for whom it is inconvenient to go to the hospital very often. PMID:25953306

  2. Effect of Processing of HIPERCO® 50 Alloy Laminates on Their Magnetic Properties

    NASA Astrophysics Data System (ADS)

    Jayaraman, Tanjore V.

    2015-11-01

    Fe-Co-based soft-magnetic materials form an important class of high-induction alloys that are widely used in energy conversion applications in the aerospace industry. In this work, the effect of processing—cut method [stamping and wire-electrical discharge machining (EDM)] and annealing (cut unannealed, cut followed by annealing, and annealing followed by cut)—on the magnetic properties of the HIPERCO® 50 Alloy laminates was investigated. A cold-rolled ˜0.006-in (˜150-μm)-thick strip of HIPERCO® 50 Alloy was cut into ring laminations and final-annealed in dry hydrogen. Scanning electron microscopy (SEM) and x-ray diffraction analysis indicated the presence of extraneous Cu on the cut edge of the wire-EDM cut ring laminates, along with the expected Fe-Co phase for HIPERCO® 50 alloy. SEM micrographs of the cut edge showed the typical sheared surface and irregular surface for stamped and wire-EDM cut ring laminates respectively. The rings that were stamped followed by annealing (STfA) showed superior direct current (DC) and alternating current (AC) magnetic properties. The presence of Cu (diamagnetic) in wire-EDM cut rings adversely affects induction ( B) and core loss ( P T), compared to the stamped rings for corresponding annealing conditions. The difference in the DC magnetic properties between the ring laminates STfA and annealed followed by stamping (AfST) was significantly large compared to that between the ring laminates that were wire-EDM cut followed by annealing (EDfA) and annealing followed by wire-EDM (AfED). This suggests that, for certain applications where the differences in DC magnetic properties between EDfA and AfED are acceptable, the AfED rings may be put to application/service after the wire-EDM cut operation, i.e. wire-EDM may be performed after `final-annealing'. However, the AC properties between EDfA and AfED rings were significantly different, hence for AC applications, the `final annealing', post-cutting, is critical irrespective of the cut method. Wire-EDM incorporates extraneous Cu on the cut edge of the HIPERCO® 50 Alloy laminates and deteriorates its magnetic properties. An intermediate grinding step after wire-EDM, for the removal of Cu, could probably improve the magnetic properties. However, if the extraneous Cu and the accompanied deterioration in magnetic properties is acceptable for certain applications, then the wire-EDM provides the flexibility to have the `final-annealing' of HIPERCO® 50 Alloy laminates either before or after wire-EDM.

  3. Machine Tool Software

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A NASA-developed software package has played a part in technical education of students who major in Mechanical Engineering Technology at William Rainey Harper College. Professor Hack has been using (APT) Automatically Programmed Tool Software since 1969 in his CAD/CAM Computer Aided Design and Manufacturing curriculum. Professor Hack teaches the use of APT programming languages for control of metal cutting machines. Machine tool instructions are geometry definitions written in APT Language to constitute a "part program." The part program is processed by the machine tool. CAD/CAM students go from writing a program to cutting steel in the course of a semester.

  4. A Prototyping Environment for Research on Human-Machine Interfaces in Process Control: Use of Microsoft WPF for Microworld and Distributed Control System Development

    SciTech Connect

    Roger Lew; Ronald L. Boring; Thomas A. Ulrich

    2014-08-01

    Operators of critical processes, such as nuclear power production, must contend with highly complex systems, procedures, and regulations. Developing human-machine interfaces (HMIs) that better support operators is a high priority for ensuring the safe and reliable operation of critical processes. Human factors engineering (HFE) provides a rich and mature set of tools for evaluating the performance of HMIs, but the set of tools for developing and designing HMIs is still in its infancy. Here we propose that Microsoft Windows Presentation Foundation (WPF) is well suited for many roles in the research and development of HMIs for process control.

  5. 29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... dead animals, animal offal, animal fats, scrap meats, blood, and bones into stock feeds, tallow... cheese, etc.): Meat patty forming machines, meat and bone cutting saws, meat slicers, knives (except... dead animals, animal offal, animal fats, scrap meats, blood, and bones into stock feeds,...

  6. Probing charged matter through h → γγ, gamma ray lines, and EDMs

    NASA Astrophysics Data System (ADS)

    Fan, JiJi; Reece, Matthew

    2013-06-01

    Numerous experiments currently underway offer the potential to indirectly probe new charged particles with masses at the weak scale. For example, the tentative excess in h → γγ decays and the tentative gamma-ray line in Fermi-LAT data have recently attracted attention as possible one-loop signatures of new charged particles. We explore the interplay between such signals, dark matter direct detection through Higgs exchange, and measurements of the electron EDM, by studying the size of these effects in several models. We compute one-loop effects to explore the relationship among couplings probed by different experiments. In particular, models in which dark matter and the Higgs both interact with charged particles at a detectable level typically induce, at loop level, couplings between dark matter and the Higgs that are around the level of current direct detection sensitivity. Intriguingly, one-loop h → γγ and DM DM → γγ, two-loop EDMs, and loop-induced direct detection rates are all coming within range of existing experiments for approximately the same range of charged particle masses, offering the prospect of an exciting coincidence of signals at collider, astrophysical, underground and atomic physics measurements.

  7. Improving the Limit on the Electron EDM: Data Acquisition and Systematics Studies in the ACME Experiment

    NASA Astrophysics Data System (ADS)

    Hess, Paul William

    The ACME collaboration has completed a measurement setting a new upper limit on the size of the electron's permanent electric dipole moment (EDM). The existence of the EDM is well motivated by theories extending the standard model of particle physics, with predicted sizes very close to the current experimental limit. The new limit was set by measuring spin precession within the metastable H state of the polar molecule thorium monoxide (ThO). A particular focus here is on the automated data acquisition system developed to search for a precession phase odd under internal and external reversal of the electric field. Automated switching of many different experimental controls allowed a rapid diagnosis of major systematics, including the dominant systematic caused by non-reversing electric fields and laser polarization gradients. Polarimetry measurements made it possible to quantify and minimize the polarization gradients in our state preparation and probe lasers. Three separate measurements were used to determine the electric field that did not reverse when we tried to switch the field direction. The new bound of | de| < 8.7 x 10--29 e·cm is over an order of magnitude smaller than previous limits, and strongly limits T-violating physics at TeV energy scales.

  8. Magnetometry in the Munich Neutron Electric Dipole Moment (nEDM) Experiment

    NASA Astrophysics Data System (ADS)

    Degenkolb, Skyler

    2013-05-01

    Neutron EDM measurements rely on sensitive magnetometry to decouple signal from systematic errors. State-of-the-art co-magnetometers use hyperpolarized diamagnetic atoms, chosen for small spin-flip cross-sections and long coherence times. In particular, the 254 nm 199Hg line is used to polarize and detect via Hg lamps or lasers. We present a comprehensive scheme of Hg co-magnetometers, external magnetometers and gradiometers inside passive and active shields. Hg gas is pumped and probed by a diode laser with two doubling stages whose UV output is locked to the 254 nm line at the point of vanishing light shift; adjacent cells containing Hg and/or other species are used to extract systematics correlated with material properties of Hg (e.g., center-of-mass displacements or georotational shifts). Vapor cell magnetometers of Hg or Cs are used for comparison, and to guide apparatus installation. The vibration-isolated experiment takes place within passive mu-metal and aluminum shields, inside a non-magnetic experimental hall. A magnetically shielded room, monitored by 180 fluxgate magnetometers which generate error signals for 24 independent external compensation coils, contains the passive shield. Design and performance of the composite system will be discussed. (for the Munich nEDM Collaboration: nedm.ph.tum.de)

  9. The effect of electro-discharge machined sonotrode topology on interlaminar bonding in ultrasonic consolidation

    NASA Astrophysics Data System (ADS)

    Edmonds, H. C.; Harris, R. A.

    2011-04-01

    Ultrasonic Consolidation (UC) is a solid state additive manufacturing process which fabricates three-dimensional objects by ultrasonically joining metal foils together, layer-by-layer, to form a solid part. This study investigates the effect of sonotrode surface texture on the bond strength, interlaminar microstructure and sample surface texture of parts fabricated by UC. White light interferometry was used to characterize the surface of two sonotrodes, textured by Electro-Discharge Machining (EDM). Aluminum 3003-H18 UC samples were fabricated using both sonotrodes under identical processing conditions. The surface texture of the UC samples produced is a reduced amplitude version of the parent sonotrodes texture. Peel testing was used to evaluate the bond strength and failure mode of the samples. The interlaminar microstructure of the parts was examined and linear weld density measured. The rougher sonotrode samples exhibited higher weld strength and brittle failure modes compared to the less rough sonotrode samples which demonstrated ductile failure and lower weld strength. This paper examines the influence of sonotrode texture on interlaminar bonding in UC and how this could be controlled and exploited to optimize bonding in UC.

  10. 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.

  11. Tool & Die and EDM Series. Educational Resources for the Machine Tool Industry. Course Syllabi, Instructor's Handbook, [and] Student Laboratory Manual.

    ERIC Educational Resources Information Center

    Texas State Technical Coll. System, Waco.

    This package consists of course syllabi, an instructor's handbook, and a student laboratory manual for a 2-year vocational training program to prepare students for entry-level employment as tool and die makers. The program was developed through a modification of the DACUM (Developing a Curriculum) technique. The course syllabi volume begins with…

  12. 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).

  13. Human-machine interactions

    DOEpatents

    Forsythe, J. Chris; Xavier, Patrick G.; Abbott, Robert G.; Brannon, Nathan G.; Bernard, Michael L.; Speed, Ann E.

    2009-04-28

    Digital technology utilizing a cognitive model based on human naturalistic decision-making processes, including pattern recognition and episodic memory, can reduce the dependency of human-machine interactions on the abilities of a human user and can enable a machine to more closely emulate human-like responses. Such a cognitive model can enable digital technology to use cognitive capacities fundamental to human-like communication and cooperation to interact with humans.

  14. Diamond machine tool face lapping machine

    DOEpatents

    Yetter, H.H.

    1985-05-06

    An apparatus for shaping, sharpening and polishing diamond-tipped single-point machine tools. The isolation of a rotating grinding wheel from its driving apparatus using an air bearing and causing the tool to be shaped, polished or sharpened to be moved across the surface of the grinding wheel so that it does not remain at one radius for more than a single rotation of the grinding wheel has been found to readily result in machine tools of a quality which can only be obtained by the most tedious and costly processing procedures, and previously unattainable by simple lapping techniques.

  15. 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

  16. Mining machine

    SciTech Connect

    Parrott, G.A.

    1985-05-07

    A haulage system for a mining machine comprises a mining machine mounted on and/or guided by a conveyor and reciprocable with respect thereto, the conveyor being provided with a rack having plural rows of teeth of identical pitch, with the teeth of one row staggered with respect to an adjacent row(s), and the machine being provided with at least one power driven haulage sprocket comprising plural sets of peripherally arranged teeth of identical pitch, one set being angularly staggered with respect to an adjacent set(s), whereby one set is engageable with each row of teeth of the rack. The invention also includes a mining machine provided with such a power driven haulage sprocket, and a rack as above described and provided with end fittings for securing in articulated manner to an adjacent rack.

  17. 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.

  18. Calculation of net emission coefficient of electrical discharge machining arc plasmas in mixtures of nitrogen with graphite, copper and tungsten

    NASA Astrophysics Data System (ADS)

    Adineh, V. R.; Coufal, O.; Bartlova, M.

    2015-10-01

    This work reports theoretical calculations of electrical discharge machining (EDM) radiative properties for mixture systems of N2-C, N2-Cu and N2-W arc plasmas, in the temperature range of 3000-10 000 K, and at 1 and 10 bar pressures. Radiative properties are computed for various plasma sizes as well as vapour proportions. Calculations consider line overlapping with spectrum coverage from 30 to 10 000 nm. Doppler, Natural, Van-der-Waals, Resonance and Stark broadening are taken into account as the line broadening mechanisms. Besides, continuum calculations consider bound-free and free-free emissions along with molecular bands radiation for selected molecular systems. Results show that contamination vapours of EDM electrode have strong influence on the amount of EDM plasma radiation to the surrounding environment. However, comparison of impurities from workpiece with electrode one indicates that Fe vapour has stronger impact on modifying the EDM arc plasma radiative properties, compared to the C, Cu and W species studied in this research.

  19. Proceedings of the International Conference on Educational Data Mining (EDM) (6th, Memphis, TN., USA, July 6-9, 2013)

    ERIC Educational Resources Information Center

    D'Mello, S. K., Ed.; Calvo, R. A., Ed.; Olney, A., Ed.

    2013-01-01

    Since its inception in 2008, the Educational Data Mining (EDM) conference series has featured some of the most innovative and fascinating basic and applied research centered on data mining, education, and learning technologies. This tradition of exemplary interdisciplinary research has been kept alive in 2013 as evident through an imaginative,…

  20. Proceedings of the International Conference on Educational Data Mining (EDM) (4th, Eindhoven, the Netherlands, July 6-8, 2011)

    ERIC Educational Resources Information Center

    Pechenizkiy, Mykola; Calders, Toon; Conati, Cristina; Ventura, Sebastian; Romero, Cristobal; Stamper, John

    2011-01-01

    The 4th International Conference on Educational Data Mining (EDM 2011) brings together researchers from computer science, education, psychology, psychometrics, and statistics to analyze large datasets to answer educational research questions. The conference, held in Eindhoven, The Netherlands, July 6-9, 2011, follows the three previous editions…

  1. Proceedings of the International Conference on Educational Data Mining (EDM) (8th, Madrid, Spain, June 26-29, 2015)

    ERIC Educational Resources Information Center

    Santos, Olga Cristina, Ed.; Boticario, Jesus Gonzalez, Ed.; Romero, Cristobal, Ed.; Pechenizkiy, Mykola, Ed.; Merceron, Agathe, Ed.; Mitros, Piotr, Ed.; Luna, Jose Maria, Ed.; Mihaescu, Cristian, Ed.; Moreno, Pablo, Ed.; Hershkovitz, Arnon, Ed.; Ventura, Sebastian, Ed.; Desmarais, Michel, Ed.

    2015-01-01

    The 8th International Conference on Educational Data Mining (EDM 2015) is held under auspices of the International Educational Data Mining Society at UNED, the National University for Distance Education in Spain. The conference held in Madrid, Spain, July 26-29, 2015, follows the seven previous editions (London 2014, Memphis 2013, Chania 2012,…

  2. Prediction of Machine Tool Condition Using Support Vector Machine

    NASA Astrophysics Data System (ADS)

    Wang, Peigong; Meng, Qingfeng; Zhao, Jian; Li, Junjie; Wang, Xiufeng

    2011-07-01

    Condition monitoring and predicting of CNC machine tools are investigated in this paper. Considering the CNC machine tools are often small numbers of samples, a condition predicting method for CNC machine tools based on support vector machines (SVMs) is proposed, then one-step and multi-step condition prediction models are constructed. The support vector machines prediction models are used to predict the trends of working condition of a certain type of CNC worm wheel and gear grinding machine by applying sequence data of vibration signal, which is collected during machine processing. And the relationship between different eigenvalue in CNC vibration signal and machining quality is discussed. The test result shows that the trend of vibration signal Peak-to-peak value in surface normal direction is most relevant to the trend of surface roughness value. In trends prediction of working condition, support vector machine has higher prediction accuracy both in the short term ('One-step') and long term (multi-step) prediction compared to autoregressive (AR) model and the RBF neural network. Experimental results show that it is feasible to apply support vector machine to CNC machine tool condition prediction.

  3. Zgoubi vs. the machines

    SciTech Connect

    Meot, Francois

    2015-05-03

    The presentation covered the following areas: Stepwise tracking numerical machinery; Polarization at RHIC complex; Polarization in eRHIC; Dynamical acceptance of eRHIC FFAG ring; Polarization in the MEIC Figure-8 collider ring; and, p-EDM ring, prospects.

  4. Preliminary study of high-speed machining

    SciTech Connect

    Jordan, R.E.

    1980-07-01

    The feasibility of a high speed machining process has been established for application to Bendix aluminum products, based upon information gained through visits to existing high speed machining facilities and by the completion of a representative Bendix part using this process. The need for an experimental high speed machining capability at Bendix for further process evaluation is established.

  5. On Machine Capacitance Dimensional and Surface Profile Measurement System

    NASA Technical Reports Server (NTRS)

    Resnick, Ralph

    1993-01-01

    A program was awarded under the Air Force Machine Tool Sensor Improvements Program Research and Development Announcement to develop and demonstrate the use of a Capacitance Sensor System including Capacitive Non-Contact Analog Probe and a Capacitive Array Dimensional Measurement System to check the dimensions of complex shapes and contours on a machine tool or in an automated inspection cell. The manufacturing of complex shapes and contours and the subsequent verification of those manufactured shapes is fundamental and widespread throughout industry. The critical profile of a gear tooth; the overall shape of a graphite EDM electrode; the contour of a turbine blade in a jet engine; and countless other components in varied applications possess complex shapes that require detailed and complex inspection procedures. Current inspection methods for complex shapes and contours are expensive, time-consuming, and labor intensive.

  6. Studies of Systematic Limitations in the EDM Searches at Storage Rings

    NASA Astrophysics Data System (ADS)

    Saleev, Artem; Nikolaev, Nikolai; Rathmann, Frank

    2016-02-01

    Searches of the electric dipole moment (EDM) at a pure magnetic ring, like COSY, encounter strong background coming from magnetic dipole moment (MDM). The most troubling issue is the MDM spin rotation in the so-called imperfection, radial and longitudinal, B-fields. To study the systematic effects of the imperfection fields at COSY we proposed the original method which makes use of the two static solenoids acting as artificial imperfections. Perturbation of the spin tune caused by the spin kicks in the solenoids probes the systematic effect of cumulative spin rotation in the imperfection fields all over the ring. The spin tune is one of the most precise quantities measured presently at COSY at 10‑10 level. The method has been successfully tested in September 2014 run at COSY, unravelling strength of spin kicks in the ring’s imperfection fields at the level of 10‑3rad.

  7. Interior Vector Magnetic Field Monitoring via External Measurements for the SNS Neutron EDM Experiment

    NASA Astrophysics Data System (ADS)

    Nouri, Nima; Brown, Michael; Carr, Robert; Filippone, Bradley; Osthelder, Charles; Plaster, Bradley; Slutsky, Simon; Swank, Christopher

    2015-10-01

    A prototype of a magnetic field monitoring system designed to reconstruct the vector magnetic field components (and, hence, all nine of the ∂Bi / ∂xj field gradients) within the interior measurement fiducial volume solely from external measurements is under development for the SNS neutron EDM experiment. A first-generation room-temperature prototype array has already been tested. A second-generation prototype array consisting of 12 cryogenic-compatible fluxgate magnetometer probes will be deployed within the cold region of the experiment's 1 / 3 -scale cryogenic magnet testing apparatus. We will report progress towards the development of this second-generation prototype. This work was supported in part by the U. S. Department of Energy Office of Nuclear Physics under Award No. DE-FG02-08ER41557.

  8. NDT Comparisons of In-Service Cracks, Manufactured Cracks and EDM Notches

    NASA Astrophysics Data System (ADS)

    Piotrowski, David; Bode, Michel D.

    2007-03-01

    Probability of Detection (POD) studies are typically conducted on EDM notches, "manufactured" crack specimens, or actual in-service crack specimens. The purpose of this paper is the education of the aerospace community in the subtle differences and benefits of using each specimen type. Data from previous POD studies are compared to data from teardown of a retired passenger aircraft, resulting in POD data from in-situ defects. Analysis of this data reveals similarities and differences between signals for four (4) types of specimens and four (4) nondestructive inspection (NDI) methods. Additionally, the paper provides an awareness of the assumptions used in each type of POD study, and potential consequences of violating such assumptions.

  9. Preliminary results of processing of Pulkovo series of photographic observations of double star 61 Cygni measured by automatic machine "Fantasy"

    NASA Astrophysics Data System (ADS)

    Gorshanov, D. L.; Shakht, N. A.; Kisselev, A. A.; Polyakov, E. V.; Bronnikova, A. A.; Kanaev, I. I.

    2003-11-01

    Two long-term series of photographic observations of one of the nearest double star 61 Cygni have been obtained at Pulkovo by means of normal astrograph in 1895-2000 (I) and by means of 26'' refractor in 1958-2000 (II). All these observations have been measured by means automatic machine "Fantasy" with mean error of yearly positions 0.016'' and 0.008'' for I and II series correspondly. The periodic deviations with period 6.4 +/- 0.5 yr in the residuals in relative distances between components are noticed for series II.

  10. Monitoring local crustal movements using high precision GPS network and EDM baseline

    NASA Astrophysics Data System (ADS)

    Ahola, J.; Ollikainen, M.

    2003-04-01

    Finnish Geodetic Institute (FGI) established in a co-operation with Posiva Ltd. high precision GPS networks at Olkiluoto, Kivetty and Romuvaara in 1994-1995. The goal of the work is to study local crustal deformations at the areas, which were selected as candidates for a disposal of spent nuclear fuel used in Finland. The studies are now concentrated at Olkiluoto, because the Government and the Parliament have ratified the positive policy decision that makes it possible to establish the final disposal at Olkiluoto. The GPS network at Olkiluoto includes ten reinforced concrete pillars located in different geological blocks. The FGI has observed the network semiannually since 1995. The GPS observations were made in 24 h sessions with Ashtech Z-12 GPS receivers equipped with Ashtech Dorne Margolin Choke Ring antennas. The computations were made with Bernese GPS software using the L1 and L2 frequencies and the ionosphere models. According to the 14 measurements campaigns the largest baselines change rates are about 0.5 mm 0.1-0.2 mm per year. We have noticed that some GPS sessions yield baseline lengths, which are systematically longer than the mean of all campaigns. The systematic error is most probably due to the ionosphere modeling. In order to solve this scaling problem we established a 511 m baseline for electronic distance measurements (EDM) between two pillars in the spring 2002. We will measure the distance between these stations with Mekometer 5000 during the GPS measurement campaigns. Two Mekometer measurements were performed in 2002. The differences between the GPS and the EDM measurements are few tenth of millimeter. More measurement campaigns are needed to determine possible crustal movements at the Olkiluoto investigation area. GPS observations and electronic distance measurements will be continued semiannually.

  11. Machining in Microgravity

    NASA Astrophysics Data System (ADS)

    Vincent, Graylan

    2003-01-01

    A CNC mill was flown aboard NASA's KC-135 ``Weightless Wonder'' microgravity research aircraft to investigate the effect of gravity on the machining process and to demonstrate the feasibility and functionality of a CNC mill in a weightless environment, such as aboard the International Space Station. The experiment hypothesis was that the surface roughness of milling cuts made in microgravity would be of higher quality than cuts made in a gravitational environment due to increased chip removal. The technical problems associated with microgravity machining (such as the chip removal and collection process), and the engineering solutions to these problems were also evaluated in this experiment.

  12. Workout Machine

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Orbotron is a tri-axle exercise machine patterned after a NASA training simulator for astronaut orientation in the microgravity of space. It has three orbiting rings corresponding to roll, pitch and yaw. The user is in the middle of the inner ring with the stomach remaining in the center of all axes, eliminating dizziness. Human power starts the rings spinning, unlike the NASA air-powered system. Marketed by Fantasy Factory (formerly Orbotron, Inc.), the machine can improve aerobic capacity, strength and endurance in five to seven minute workouts.

  13. Improvement of reliability of welding by in-process sensing and control (development of smart welding machines for girth welding of pipes). Final report

    SciTech Connect

    Hardt, D.E.; Masubuchi, K.; Paynter, H.M.; Unkel, W.C.

    1983-04-01

    Closed-loop control of the welding variables represents a promising, cost-effective approach to improving weld quality and therefore reducing the total cost of producing welded structures. The ultimate goal is to place all significant weld variables under direct closed-loop control; this contrasts with preprogrammed machines which place the welding equipment under control. As the first step, an overall strategy has been formulated and an investigation of weld pool geometry control for gas tungsten arc process has been completed. The research activities were divided into the areas of arc phenomena, weld pool phenomena, sensing techniques and control activities.

  14. Machine tool evaluation and machining operation development

    SciTech Connect

    Morris, T.O.; Kegg, R.

    1997-03-15

    The purpose of this CRADA was to support Cincinnati Milacron`s needs in fabricating precision components, from difficult to machine materials, while maintaining and enhancing the precision manufacturing skills of the Oak Ridge Complex. Oak Ridge and Cincinnati Milacron personnel worked in a team relationship wherein each contributed equally to the success of the program. Process characterization, control technologies, machine tool capabilities, and environmental issues were the primary focus areas. In general, Oak Ridge contributed a wider range of expertise in machine tool testing and monitoring, and environmental testing on machining fluids to the defined tasks while Cincinnati Milacron personnel provided equipment, operations-specific knowledge and shop-floor services to each task. Cincinnati Milacron was very pleased with the results of all of the CRADA tasks. However, some of the environmental tasks were not carried through to a desired completion due to an expanding realization of need as the work progressed. This expansion of the desired goals then exceeded the time length of the CRADA. Discussions are underway on continuing these tasks under either a Work for Others agreement or some alternate funding.

  15. Employing Ti nano-powder dielectric to enhance surface characteristics in electrical discharge machining of AISI D2 steel

    NASA Astrophysics Data System (ADS)

    Marashi, Houriyeh; Sarhan, Ahmed A. D.; Hamdi, Mohd

    2015-12-01

    Manufacturing components with superior surface characteristics is challenging when electrical discharge machining (EDM) is employed for mass production. The aim of this research is to enhance the characteristics of AISI D2 steel surface machined with EDM through adding Ti nano-powder to dielectric under various machining parameters, including discharge duration (Ton) and peak current (I). Surface roughness profilometer, FESEM and AFM analysis were utilized to reveal the machined surface characteristics in terms of surface roughness, surface morphology and surface micro-defects. Moreover, EDX analysis was performed in order to evaluate the atomic deposition of Ti nano-powder on the surface. The concentration of Ti nano-powder in dielectric was also examined using ESEM and EDX. According to the results, the addition of Ti nano-powder to dielectric notably enhanced the surface morphology and surface roughness at all machining parameters except Ton = 340 μs. Of these parameters, maximum enhancement was observed at Ton = 210 μs, where the material removal rate and average surface roughness improved by ∼69 and ∼35% for peak current of 6 and 12 A, respectively. Elemental analysis signified negligible Ti deposition on the machined surface while the atomic concentration of Ti was increased around the crack areas.

  16. Wacky Machines

    ERIC Educational Resources Information Center

    Fendrich, Jean

    2002-01-01

    Collectors everywhere know that local antique shops and flea markets are treasure troves just waiting to be plundered. Science teachers might take a hint from these hobbyists, for the next community yard sale might be a repository of old, quirky items that are just the things to get students thinking about simple machines. By introducing some…

  17. Multi-objective optimization of process parameters in Electro-Discharge Diamond Face Grinding based on ANN-NSGA-II hybrid technique

    NASA Astrophysics Data System (ADS)

    Yadav, Ravindra Nath; Yadava, Vinod; Singh, G. K.

    2013-09-01

    The effective study of hybrid machining processes (HMPs), in terms of modeling and optimization has always been a challenge to the researchers. The combined approach of Artificial Neural Network (ANN) and Non-Dominated Sorting Genetic Algorithm-II (NSGA-II) has attracted attention of researchers for modeling and optimization of the complex machining processes. In this paper, a hybrid machining process of Electrical Discharge Face Grinding (EDFG) and Diamond Face Grinding (DFG) named as Electrical Discharge Diamond face Grinding (EDDFG) have been studied using a hybrid methodology of ANN-NSGA-II. In this study, ANN has been used for modeling while NSGA-II is used to optimize the control parameters of the EDDFG process. For observations of input-output relations, the experiments were conducted on a self developed face grinding setup, which is attached with the ram of EDM machine. During experimentation, the wheel speed, pulse current, pulse on-time and duty factor are taken as input parameters while output parameters are material removal rate (MRR) and average surface roughness ( R a). The results have shown that the developed ANN model is capable to predict the output responses within the acceptable limit for a given set of input parameters. It has also been found that hybrid approach of ANN-NSGAII gives a set of optimal solutions for getting appropriate value of outputs with multiple objectives.

  18. Development of an electric field application system with transparent electrodes towards the electron EDM measurement with laser-cooled Fr atoms

    NASA Astrophysics Data System (ADS)

    Ishikawa, Taisuke; Ando, Shun; Aoki, Takahiro; Arikawa, Hiroshi; Harada, Ken-Ichi; Hayamizu, Tomohiro; Inoue, Takeshi; Itoh, Masatoshi; Kawamura, Hirokazu; Kato, Ko; Sakamoto, Kosuke; Uchiyama, Aiko; Sakemi, Yasuhiro

    2014-09-01

    The permanent electric dipole moment (EDM) of elementary particles is a good probe for new physics beyond the standard model. Since the francium (Fr) atom has a large enhancement factor of the electron EDM and laser-cooled atoms can have long coherence times, we plan to utilize laser-cooled Fr atoms for the electron EDM search experiment. Besides, a strong electric field is one of key issues for the EDM experiment. Recently, we have embarked on a development of the electric field application system with transparent electrodes coated by tin-doped indium oxide (ITO). The ITO electrodes break the difficulty in the coexistence of electrodes with several cooling laser lights. The actual electric field applied to the atom is evaluated by measuring the dc Stark shift for the laser-cooled rubidium atoms. In this presentation, the present status of the electric field application system will be reported. The permanent electric dipole moment (EDM) of elementary particles is a good probe for new physics beyond the standard model. Since the francium (Fr) atom has a large enhancement factor of the electron EDM and laser-cooled atoms can have long coherence times, we plan to utilize laser-cooled Fr atoms for the electron EDM search experiment. Besides, a strong electric field is one of key issues for the EDM experiment. Recently, we have embarked on a development of the electric field application system with transparent electrodes coated by tin-doped indium oxide (ITO). The ITO electrodes break the difficulty in the coexistence of electrodes with several cooling laser lights. The actual electric field applied to the atom is evaluated by measuring the dc Stark shift for the laser-cooled rubidium atoms. In this presentation, the present status of the electric field application system will be reported. This work is supported by Grants-in-Aid for Scientific Research (No. 26220705) and Tohoku University's Focused Research Project.

  19. Formal modeling of virtual machines

    NASA Technical Reports Server (NTRS)

    Cremers, A. B.; Hibbard, T. N.

    1978-01-01

    Systematic software design can be based on the development of a 'hierarchy of virtual machines', each representing a 'level of abstraction' of the design process. The reported investigation presents the concept of 'data space' as a formal model for virtual machines. The presented model of a data space combines the notions of data type and mathematical machine to express the close interaction between data and control structures which takes place in a virtual machine. One of the main objectives of the investigation is to show that control-independent data type implementation is only of limited usefulness as an isolated tool of program development, and that the representation of data is generally dictated by the control context of a virtual machine. As a second objective, a better understanding is to be developed of virtual machine state structures than was heretofore provided by the view of the state space as a Cartesian product.

  20. Machine Learning

    NASA Astrophysics Data System (ADS)

    Hoffmann, Achim; Mahidadia, Ashesh

    The purpose of this chapter is to present fundamental ideas and techniques of machine learning suitable for the field of this book, i.e., for automated scientific discovery. The chapter focuses on those symbolic machine learning methods, which produce results that are suitable to be interpreted and understood by humans. This is particularly important in the context of automated scientific discovery as the scientific theories to be produced by machines are usually meant to be interpreted by humans. This chapter contains some of the most influential ideas and concepts in machine learning research to give the reader a basic insight into the field. After the introduction in Sect. 1, general ideas of how learning problems can be framed are given in Sect. 2. The section provides useful perspectives to better understand what learning algorithms actually do. Section 3 presents the Version space model which is an early learning algorithm as well as a conceptual framework, that provides important insight into the general mechanisms behind most learning algorithms. In section 4, a family of learning algorithms, the AQ family for learning classification rules is presented. The AQ family belongs to the early approaches in machine learning. The next, Sect. 5 presents the basic principles of decision tree learners. Decision tree learners belong to the most influential class of inductive learning algorithms today. Finally, a more recent group of learning systems are presented in Sect. 6, which learn relational concepts within the framework of logic programming. This is a particularly interesting group of learning systems since the framework allows also to incorporate background knowledge which may assist in generalisation. Section 7 discusses Association Rules - a technique that comes from the related field of Data mining. Section 8 presents the basic idea of the Naive Bayesian Classifier. While this is a very popular learning technique, the learning result is not well suited for human comprehension as it is essentially a large collection of probability values. In Sect. 9, we present a generic method for improving accuracy of a given learner by generatingmultiple classifiers using variations of the training data. While this works well in most cases, the resulting classifiers have significantly increased complexity and, hence, tend to destroy the human readability of the learning result that a single learner may produce. Section 10 contains a summary, mentions briefly other techniques not discussed in this chapter and presents outlook on the potential of machine learning in the future.

  1. Machine-Aided Indexing for NASA STI.

    ERIC Educational Resources Information Center

    Wilson, John

    1987-01-01

    Describes the use of machine aided indexing as part of NASA's information systems. The discussion covers reasons for incorporating machine aided indexing, the lexical dictionary used, subject switching, natural language processing, benefits to the system, and possible future developments. (CLB)

  2. Introduction to Exploring Machines

    ERIC Educational Resources Information Center

    Early Childhood Today, 2006

    2006-01-01

    Young children are fascinated by how things "work." They are at a stage of development where they want to experiment with the many ways to use an object or take things apart and put them back together. In the process of exploring tools and machines, children use the scientific method and problem-solving skills. They observe how things work, wonder…

  3. The Answer Machine.

    ERIC Educational Resources Information Center

    Feldman, Susan

    2000-01-01

    Discusses information retrieval systems and the need to have them adapt to user needs, integrate information in any format, reveal patterns and trends in information, and answer questions. Topics include statistics and probability; natural language processing; intelligent agents; concept mapping; machine-aided indexing; text mining; filtering;…

  4. Cleaning of Free Machining Brass

    SciTech Connect

    Shen, T

    2005-12-29

    We have investigated four brightening treatments proposed by two cleaning vendors for cleaning free machining brass. The experimental results showed that none of the proposed brightening treatments passed the swipe test. Thus, we maintain the recommendation of not using the brightening process in the cleaning of free machining brass for NIF application.

  5. CATSI EDM: a new sensor for the real-time passive stand-off detection and identification of chemicals

    NASA Astrophysics Data System (ADS)

    Thériault, Jean-Marc; Lacasse, Paul; Lavoie, Hugo; Bouffard, François; Montembeault, Yan; Farley, Vincent; Belhumeur, Louis; Lagueux, Philippe

    2010-04-01

    DRDC Valcartier recently completed the development of the CATSI EDM (Compact Atmospheric Sounding Interferometer Engineering Development Model) for the Canadian Forces (CF). It is a militarized sensor designed to meet the needs of the CF in the development of area surveillance capabilities for the detection and identification of chemical Warfare Agents (CWA) and toxic industrial chemicals (TIC). CATSI EDM is a passive infrared double-beam Fourier spectrometer system designed for real-time stand-off detection and identification of chemical vapours at distances up to 5 km. It is based on the successful passive differential detection technology. This technique known as optical subtraction, results in a target gas spectrum which is almost free of background, thus making possible detection of weak infrared emission in strong background emission. This paper summarizes the system requirements, achievements, hardware and software characteristics and test results.

  6. Automated fiber pigtailing machine

    DOEpatents

    Strand, O.T.; Lowry, M.E.

    1999-01-05

    The Automated Fiber Pigtailing Machine (AFPM) aligns and attaches optical fibers to optoelectronic (OE) devices such as laser diodes, photodiodes, and waveguide devices without operator intervention. The so-called pigtailing process is completed with sub-micron accuracies in less than 3 minutes. The AFPM operates unattended for one hour, is modular in design and is compatible with a mass production manufacturing environment. This machine can be used to build components which are used in military aircraft navigation systems, computer systems, communications systems and in the construction of diagnostics and experimental systems. 26 figs.

  7. Automated fiber pigtailing machine

    DOEpatents

    Strand, Oliver T.; Lowry, Mark E.

    1999-01-01

    The Automated Fiber Pigtailing Machine (AFPM) aligns and attaches optical fibers to optoelectonic (OE) devices such as laser diodes, photodiodes, and waveguide devices without operator intervention. The so-called pigtailing process is completed with sub-micron accuracies in less than 3 minutes. The AFPM operates unattended for one hour, is modular in design and is compatible with a mass production manufacturing environment. This machine can be used to build components which are used in military aircraft navigation systems, computer systems, communications systems and in the construction of diagnostics and experimental systems.

  8. Fullerene Machines

    NASA Technical Reports Server (NTRS)

    Globus, Al; Saini, Subhash

    1998-01-01

    Recent computational efforts at NASA Ames Research Center and computation and experiment elsewhere suggest that a nanotechnology of machine phase functionalized fullerenes may be synthetically accessible and of great interest. We have computationally demonstrated that molecular gears fashioned from (14,0) single-walled carbon nanotubes and benzyne teeth should operate well at 50-100 gigahertz. Preliminary results suggest that these gears can be cooled by a helium atmosphere and a laser motor can power fullerene gears if a positive and negative charge have been added to form a dipole. In addition, we have unproven concepts based on experimental and computational evidence for support structures, computer control, a system architecture, a variety of components, and manufacture. Combining fullerene machines with the remarkable mechanical properties of carbon nanotubes, there is some reason to believe that a focused effort to develop fullerene nanotechnology could yield materials with tremendous properties.

  9. Induction machine

    DOEpatents

    Owen, Whitney H.

    1980-01-01

    A polyphase rotary induction machine for use as a motor or generator utilizing a single rotor assembly having two series connected sets of rotor windings, a first stator winding disposed around the first rotor winding and means for controlling the current induced in one set of the rotor windings compared to the current induced in the other set of the rotor windings. The rotor windings may be wound rotor windings or squirrel cage windings.

  10. Machine performance assessment and enhancement for a hexapod machine

    SciTech Connect

    Mou, J.I.; King, C.

    1998-03-19

    The focus of this study is to develop a sensor fused process modeling and control methodology to model, assess, and then enhance the performance of a hexapod machine for precision product realization. Deterministic modeling technique was used to derive models for machine performance assessment and enhancement. Sensor fusion methodology was adopted to identify the parameters of the derived models. Empirical models and computational algorithms were also derived and implemented to model, assess, and then enhance the machine performance. The developed sensor fusion algorithms can be implemented on a PC-based open architecture controller to receive information from various sensors, assess the status of the process, determine the proper action, and deliver the command to actuators for task execution. This will enhance a hexapod machine`s capability to produce workpieces within the imposed dimensional tolerances.

  11. Experimental study of micro electrical discharge machining discharges

    SciTech Connect

    Braganca, I. M. F.; Rosa, P. A. R.; Martins, P. A. F.; Dias, F. M.; Alves, L. L.

    2013-06-21

    Micro electrical discharge machining ({mu}EDM) is an atmospheric-pressure plasma-assisted technology that uses point-to-plane discharges in liquid dielectrics to remove microscopic quantities of electrically conductive materials. In this work, an innovative {mu}EDM prototype machine was specifically designed and fabricated to produce and control single spark discharges, thus, resolving the typical limitations of (multi-discharge) commercial machines. The work analyses the type of discharge and the micro-plasma electron-density values obtained for 0.5-38 {mu}m gap sizes, 3-10 000 {mu}s pulse durations, 75-250 V low breakdown voltages, and 1-20 A discharge currents, using different combinations of metallic electrodes in oil and in water. Results allow fitting, for micro-scale and low voltages, an empirical law between the maximum gap-size for breakdown, the breakdown voltage, and the effective stress-time. The electron density n{sub e} is obtained by optical emission spectroscopy diagnostics of the H{sub {alpha}}-line Stark broadening (yielding n{sub e}{approx}10{sup 16}-10{sup 17} cm{sup -3}, i.e., ionization degrees of {approx}2 Multiplication-Sign 10{sup -5}-10{sup -4}) and by a semi-empirical resistive plasma model. The model uses the experimental values of several electrical and geometrical quantities, and of the gas pressure estimated as {approx}60 bar-2 kbar from measurements of the plasma mechanical action, obtained using a force sensor. The quantitative information of this phenomenological study can assist the optimization of this micro-fabrication technique.

  12. Experimental study of micro electrical discharge machining discharges

    NASA Astrophysics Data System (ADS)

    Bragança, I. M. F.; Rosa, P. A. R.; Dias, F. M.; Martins, P. A. F.; Alves, L. L.

    2013-06-01

    Micro electrical discharge machiningEDM) is an atmospheric-pressure plasma-assisted technology that uses point-to-plane discharges in liquid dielectrics to remove microscopic quantities of electrically conductive materials. In this work, an innovative μEDM prototype machine was specifically designed and fabricated to produce and control single spark discharges, thus, resolving the typical limitations of (multi-discharge) commercial machines. The work analyses the type of discharge and the micro-plasma electron-density values obtained for 0.5-38 μm gap sizes, 3-10 000 μs pulse durations, 75-250 V low breakdown voltages, and 1-20 A discharge currents, using different combinations of metallic electrodes in oil and in water. Results allow fitting, for micro-scale and low voltages, an empirical law between the maximum gap-size for breakdown, the breakdown voltage, and the effective stress-time. The electron density ne is obtained by optical emission spectroscopy diagnostics of the Hα-line Stark broadening (yielding ne˜1016-1017 cm-3, i.e., ionization degrees of ˜2×10-5-10-4) and by a semi-empirical resistive plasma model. The model uses the experimental values of several electrical and geometrical quantities, and of the gas pressure estimated as ˜60 bar-2 kbar from measurements of the plasma mechanical action, obtained using a force sensor. The quantitative information of this phenomenological study can assist the optimization of this micro-fabrication technique.

  13. Extensive Frequency Comb Velocity Modulation Spectroscopy of ThF^+ for Use in the Jila Electron Edm Experiment

    NASA Astrophysics Data System (ADS)

    Gresh, Dan; Cossel, Kevin; Ye, Jun; Cornell, Eric

    2014-06-01

    The metastable ^3Δ_1 state in trapped HfF^+ is being used for an ongoing measurement of the electron electric dipole moment (eEDM) ThF^+, which has a larger effective electric field and a longer-lived ^3Δ_1 state, offers increased sensitivity for an eEDM measurement. Recently, the Heaven group has spectroscopically studied the low-lying states of ThF^+. However, to date there is no detailed information available about technically-accessible laser transitions in the near-infrared region of the spectrum, which are necessary for state preparation and detection in an eEDM experiment. By applying the technique of frequency comb velocity modulation spectroscopy (VMS) to ThF^+ we can acquire 150 cm-1 of continuous, ion-sensitive spectra with 150 MHz resolution in 25 minutes. Here, we report on extensive broadband, high-resolution survey spectroscopy of ThF^+ in the near-IR where we have observed and accurately fit several rovibronic transitions. In addition, we have observed and characterized numerous rovibronic transitions from an unknown thoriated species of molecular ions. H. Loh, K. C. Cossel, M. C. Grau, K.-K. Ni, E. R. Meyer, J. L. Bohn, J. Ye, E. A. Cornell, Science 342, 1220 (2013). B. J. Barker, I. O. Antonov, M. C. Heaven, K. A. Peterson, J. Chem. Phys. 136, 104305 (2012). L. C. Sinclair, K. C. Cossel, T. Coffey, J. Ye, E. A. Cornell, PRL 107, 093002 (2011).

  14. Stochastic flow shop scheduling of overlapping jobs on tandem machines in application to optimizing the US Army's deliberate nuclear, biological, and chemical decontamination process, (final report). Master's thesis

    SciTech Connect

    Novikov, V.

    1991-05-01

    The U.S. Army's detailed equipment decontamination process is a stochastic flow shop which has N independent non-identical jobs (vehicles) which have overlapping processing times. This flow shop consists of up to six non-identical machines (stations). With the exception of one station, the processing times of the jobs are random variables. Based on an analysis of the processing times, the jobs for the 56 Army heavy division companies were scheduled according to the best shortest expected processing time - longest expected processing time (SEPT-LEPT) sequence. To assist in this scheduling the Gap Comparison Heuristic was developed to select the best SEPT-LEPT schedule. This schedule was then used in balancing the detailed equipment decon line in order to find the best possible site configuration subject to several constraints. The detailed troop decon line, in which all jobs are independent and identically distributed, was then balanced. Lastly, an NBC decon optimization computer program was developed using the scheduling and line balancing results. This program serves as a prototype module for the ANBACIS automated NBC decision support system.... Decontamination, Stochastic flow shop, Scheduling, Stochastic scheduling, Minimization of the makespan, SEPT-LEPT Sequences, Flow shop line balancing, ANBACIS.

  15. Surface characterization and in vivo evaluation of laser sintered and machined implants followed by resorbable-blasting media process: A study in sheep

    PubMed Central

    Bowers, Michelle; Yoo, Daniel; Marin, Charles; Gil, Luiz; Shabaka, Nour; Goldstein, Matt; Janal, Malvin; Tovar, Nick; Bonfante, Estevam; Coelho, Paulo

    2016-01-01

    Background This study aimed to compare the histomorphometric and histological bone response to laser-sintered implants followed by resorbable-blasting media (RBM) process relative to standard machined/RBM surface treated implants. Material and Methods Six male sheep (n=6) received 2 Ti-6Al-4V implants (1 per surface) in each side of the mandible for 6 weeks in vivo. The histomorphometric parameters bone-implant contact (BIC) and bone area fraction occupancy (BAFO) were evaluated. Results Optical interferometry revealed higher Sa and Sq values for the laser-sintered/RBM surface in relation to standard/RBM implants. No significant differences in BIC were observed between the two groups (p>0.2), but significantly higher BAFO was observed for standard/RBM implants (p<0.01). Conclusions The present study demonstrated that both surfaces were biocompatible and osseoconductive, and the combination of laser sintering and RBM has no advantage over the standard machined implants with subsequent RBM. Key words:Dental implants, osseointegration, resorbable- blasting media, sheep, in vivo. PMID:26827064

  16. Machinability of Stellite 6 hardfacing

    NASA Astrophysics Data System (ADS)

    Benghersallah, M.; Boulanouar, L.; Le Coz, G.; Devillez, A.; Dudzinski, D.

    2010-06-01

    This paper reports some experimental findings concerning the machinability at high cutting speed of nickel-base weld-deposited hardfacings for the manufacture of hot tooling. The forging work involves extreme impacts, forces, stresses and temperatures. Thus, mould dies must be extremely resistant. The aim of the project is to create a rapid prototyping process answering to forging conditions integrating a Stellite 6 hardfacing deposed PTA process. This study talks about the dry machining of the hardfacing, using a two tips machining tool and a high speed milling machine equipped by a power consumption recorder Wattpilote. The aim is to show the machinability of the hardfacing, measuring the power and the tip wear by optical microscope and white light interferometer, using different strategies and cutting conditions.

  17. Fast Booting Many Similar Virtual Machines

    NASA Astrophysics Data System (ADS)

    Wang, Xiaolin; Wang, Zhenlin; Liang, Shuang; Zhang, Zhengyi; Luo, Yingwei; Li, Xiaoming

    Virtual Machines have been commonly used for server consolidation in data centers, network classrooms, and cloud computing environments. Although booting up a virtual machine takes much less time than booting up a physical computer, booting up multiple virtual machines on a single physical server still takes a lot of time. We propose a method to speed up the booting process when a set of similar virtual machines share a snapshot enabled storage. Our method exploits massive memory page sharing stemming from the reads to common disk blocks by these virtual machines. Our experiments show that the second virtual machine may reduce the booting time by half.

  18. Development of high-homogeneity magnetic field coil for 129Xe EDM experiment

    NASA Astrophysics Data System (ADS)

    Sakamoto, Y.; Bidinosti, C. P.; Ichikawa, Y.; Sato, T.; Ohtomo, Y.; Kojima, S.; Funayama, C.; Suzuki, T.; Tsuchiya, M.; Furukawa, T.; Yoshimi, A.; Ino, T.; Ueno, H.; Matsuo, Y.; Fukuyama, T.; Asahi, K.

    2015-04-01

    We search for 129Xe EDM by using an active nuclear spin maser. In this experiment, the amplitude of the maser oscillation signal is one of the most important parameters that eventually determine the frequency precision. The amplitude is proportional to the ratio of the transverse spin relaxation time T 2 to the effective longitudinal spin relaxation time . In particular, for a spin maser of 3He (a co-magnetometer) for which typically reaches ˜50 h, a long T 2 is needed. T 2 depends on the homogeneity of the magnetic field which is applied with coils in order to keep the spins under precession. In the present report, we discuss on the design and construction of a new coil which provided a root-mean square (rms) field gradient of less than 5.0 μG/cm. The result of the field measurement has shown that the field gradient in the cell fulfills the target condition , and in fact T 2 of 3He has been measured to be as long as 11,000 s.

  19. TEMPO machine

    SciTech Connect

    Rohwein, G.J.; Lancaster, K.T.; Lawson, R.N.

    1986-06-01

    TEMPO is a transformer powered megavolt pulse generator with an output pulse of 100 ns duration. The machine was designed for burst mode operation at pulse repetition rates up to 10 Hz with minimum pulse-to-pulse voltage variations. To meet the requirement for pulse duration a nd a 20-..omega.. output impedance within reasonable size constraints, the pulse forming transmission line was designed as two parallel water-insulated, strip-type Blumleins. Stray capacitance and electric fields along the edges of the line elements were controlled by lining the tank with plastic sheet.

  20. An evaluation of machine processing techniques of ERTS-1 data for user applications. [urban land use and soil association mapping in Indiana

    NASA Technical Reports Server (NTRS)

    Landgrebe, D.

    1974-01-01

    A broad study is described to evaluate a set of machine analysis and processing techniques applied to ERTS-1 data. Based on the analysis results in urban land use analysis and soil association mapping together with previously reported results in general earth surface feature identification and crop species classification, a profile of general applicability of this procedure is beginning to emerge. Put in the hands of a user who knows well the information needed from the data and also is familiar with the region to be analyzed it appears that significantly useful information can be generated by these methods. When supported by preprocessing techniques such as the geometric correction and temporal registration capabilities, final products readily useable by user agencies appear possible. In parallel with application, through further research, there is much potential for further development of these techniques both with regard to providing higher performance and in new situations not yet studied.

  1. 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…

  2. CNC Machining Of The Complex Copper Electrodes

    NASA Astrophysics Data System (ADS)

    Popan, Ioan Alexandru; Balc, Nicolae; Popan, Alina

    2015-07-01

    This paper presents the machining process of the complex copper electrodes. Machining of the complex shapes in copper is difficult because this material is soft and sticky. This research presents the main steps for processing those copper electrodes at a high dimensional accuracy and a good surface quality. Special tooling solutions are required for this machining process and optimal process parameters have been found for the accurate CNC equipment, using smart CAD/CAM software.

  3. Artificial neural networks to model formulation-property correlations in the process of inline-compounding on an injection moulding machine

    NASA Astrophysics Data System (ADS)

    Moritzer, Elmar; Müller, Ellen; Martin, Yannick; Kleeschulte, Rainer

    2015-05-01

    Today the global market poses great challenges for industrial product development. Complexity, diversity of variants, flexibility and individuality are just some of the features that products have to offer today. In addition, the product series have shorter lifetimes. Because of their high capacity for adaption, polymers are increasingly able to displace traditional materials such as wood, glass and metals from various fields of application. Polymers can only be used to substitute other materials, however, if they are optimally suited to the applications in question. Hence, product-specific material development is becoming increasingly important. Integrating the compounding step in the injection moulding process permits a more efficient and faster development process for a new polymer formulation, making it possible to create new product-specific materials. This process is called inline-compounding on an injection moulding machine. The entire process sequence is supported by software from Bayer Technology called Product Design Workbench (PDWB), which provides assistance in all the individual steps from data management, via analysis and model compilation, right through to the optimization of the formulation and the design of experiments. The software is based on artificial neural networks and can model the formulation-property correlations and thus enable different formulations to be optimized. In the study presented, the workflow and the modelling with the software are presented.

  4. The influence of different screw concepts while processing fibre reinforced thermoplastics with the concept of inline-compounding on an injection moulding machine

    NASA Astrophysics Data System (ADS)

    Moritzer, E.; Müller, E.; Kleeschulte, R.

    2014-05-01

    Today, the global market poses major challenges for industrial product development. Complexity, the wide range of variants, flexibility and individuality are just some of the features that products have to fulfil. Product series additionally have shorter and shorter lifetimes. Because of their high capacity for adaptation, polymers are increasingly able to substitute traditional materials such as wood, glass and metals in various fields of application [1]. But polymers can only substitute other materials if they are optimally suited to the applications in question. Hence, product-specific material development is becoming increasingly important [2]. The problem is that the traditional development process for new polymer formulations is much too complex, too slow and therefore too expensive. Product-specific material development is thus out of the question for most processors. Integrating the compounding step in the injection moulding process would lead to a more efficient and faster development process for a new polymer formulation, providing an opportunity to create new product-specific materials. This process is called inline-compounding on an injection moulding machine. In order to develop this innovative formulation concept, with the focus on fibre reinforced thermoplastics, different screw-concepts are compared with regard to the resultant performance characteristics in the part, such as mechanical properties and fibre length distribution.

  5. Artificial Molecular Machines.

    PubMed

    Balzani; Credi; Raymo; Stoddart

    2000-10-01

    The miniaturization of components used in the construction of working devices is being pursued currently by the large-downward (top-down) fabrication. This approach, however, which obliges solid-state physicists and electronic engineers to manipulate progressively smaller and smaller pieces of matter, has its intrinsic limitations. An alternative approach is a small-upward (bottom-up) one, starting from the smallest compositions of matter that have distinct shapes and unique properties-namely molecules. In the context of this particular challenge, chemists have been extending the concept of a macroscopic machine to the molecular level. A molecular-level machine can be defined as an assembly of a distinct number of molecular components that are designed to perform machinelike movements (output) as a result of an appropriate external stimulation (input). In common with their macroscopic counterparts, a molecular machine is characterized by 1) the kind of energy input supplied to make it work, 2) the nature of the movements of its component parts, 3) the way in which its operation can be monitored and controlled, 4) the ability to make it repeat its operation in a cyclic fashion, 5) the timescale needed to complete a full cycle of movements, and 6) the purpose of its operation. Undoubtedly, the best energy inputs to make molecular machines work are photons or electrons. Indeed, with appropriately chosen photochemically and electrochemically driven reactions, it is possible to design and synthesize molecular machines that do work. Moreover, the dramatic increase in our fundamental understanding of self-assembly and self-organizational processes in chemical synthesis has aided and abetted the construction of artificial molecular machines through the development of new methods of noncovalent synthesis and the emergence of supramolecular assistance to covalent synthesis as a uniquely powerful synthetic tool. The aim of this review is to present a unified view of the field of molecular machines by focusing on past achievements, present limitations, and future perspectives. After analyzing a few important examples of natural molecular machines, the most significant developments in the field of artificial molecular machines are highlighted. The systems reviewed include 1) chemical rotors, 2) photochemically and electrochemically induced molecular (conformational) rearrangements, and 3) chemically, photochemically, and electrochemically controllable (co-conformational) motions in interlocked molecules (catenanes and rotaxanes), as well as in coordination and supramolecular complexes, including pseudorotaxanes. Artificial molecular machines based on biomolecules and interfacing artificial molecular machines with surfaces and solid supports are amongst some of the cutting-edge topics featured in this review. The extension of the concept of a machine to the molecular level is of interest not only for the sake of basic research, but also for the growth of nanoscience and the subsequent development of nanotechnology. PMID:11091368

  6. Parallel machines: Parallel machine languages

    SciTech Connect

    Iannucci, R.A. )

    1990-01-01

    This book presents a framework for understanding the tradeoffs between the conventional view and the dataflow view with the objective of discovering the critical hardware structures which must be present in any scalable, general-purpose parallel computer to effectively tolerate latency and synchronization costs. The author presents an approach to scalable general purpose parallel computation. Linguistic Concerns, Compiling Issues, Intermediate Language Issues, and hardware/technological constraints are presented as a combined approach to architectural Develoement. This book presents the notion of a parallel machine language.

  7. Managing the Complexity of Human/Machine Interactions in Computerized Learning Environments: Guiding Students' Command Process through Instrumental Orchestrations

    ERIC Educational Resources Information Center

    Trouche, Luc

    2004-01-01

    After an introduction which addresses some basic questions, this article is organized around three points: (1) The theoretical framework of the so-called "instrumental approach" which has been a theme in the last two CAME symposia; (2) A consideration of two processes ("instrumentalization" and "instrumentation") which interact in the…

  8. Urban land use mapping by machine processing of ERTS-1 multispectral data: A San Francisco Bay area example

    NASA Technical Reports Server (NTRS)

    Ellefsen, R.; Swain, P. H.; Wray, J. R.

    1973-01-01

    The study is reported to develop computer produced urban land use maps using multispectral scanner data from a satellite is reported. Data processing is discussed along with the results of the San Francisco Bay area, which was chosen as the test area.

  9. Laser machining of explosives

    DOEpatents

    Perry, Michael D.; Stuart, Brent C.; Banks, Paul S.; Myers, Booth R.; Sefcik, Joseph A.

    2000-01-01

    The invention consists of a method for machining (cutting, drilling, sculpting) of explosives (e.g., TNT, TATB, PETN, RDX, etc.). By using pulses of a duration in the range of 5 femtoseconds to 50 picoseconds, extremely precise and rapid machining can be achieved with essentially no heat or shock affected zone. In this method, material is removed by a nonthermal mechanism. A combination of multiphoton and collisional ionization creates a critical density plasma in a time scale much shorter than electron kinetic energy is transferred to the lattice. The resulting plasma is far from thermal equilibrium. The material is in essence converted from its initial solid-state directly into a fully ionized plasma on a time scale too short for thermal equilibrium to be established with the lattice. As a result, there is negligible heat conduction beyond the region removed resulting in negligible thermal stress or shock to the material beyond a few microns from the laser machined surface. Hydrodynamic expansion of the plasma eliminates the need for any ancillary techniques to remove material and produces extremely high quality machined surfaces. There is no detonation or deflagration of the explosive in the process and the material which is removed is rendered inert.

  10. Automated characterisation of ultrasound images of ovarian tumours: the diagnostic accuracy of a support vector machine and image processing with a local binary pattern operator

    PubMed Central

    Khazendar, S.; Sayasneh, A.; Al-Assam, H.; Du, H.; Kaijser, J.; Ferrara, L.; Timmerman, D.; Jassim, S.; Bourne, T.

    2015-01-01

    Introduction: Preoperative characterisation of ovarian masses into benign or malignant is of paramount importance to optimise patient management. Objectives: In this study, we developed and validated a computerised model to characterise ovarian masses as benign or malignant. Materials and methods: Transvaginal 2D B mode static ultrasound images of 187 ovarian masses with known histological diagnosis were included. Images were first pre-processed and enhanced, and Local Binary Pattern Histograms were then extracted from 2 × 2 blocks of each image. A Support Vector Machine (SVM) was trained using stratified cross validation with randomised sampling. The process was repeated 15 times and in each round 100 images were randomly selected. Results: The SVM classified the original non-treated static images as benign or malignant masses with an average accuracy of 0.62 (95% CI: 0.59-0.65). This performance significantly improved to an average accuracy of 0.77 (95% CI: 0.75-0.79) when images were pre-processed, enhanced and treated with a Local Binary Pattern operator (mean difference 0.15: 95% 0.11-0.19, p < 0.0001, two-tailed t test). Conclusion: We have shown that an SVM can classify static 2D B mode ultrasound images of ovarian masses into benign and malignant categories. The accuracy improves if texture related LBP features extracted from the images are considered. PMID:25897367

  11. Software sensors for biomass concentration in a SSC process using artificial neural networks and support vector machine.

    PubMed

    Acuña, Gonzalo; Ramirez, Cristian; Curilem, Millaray

    2014-01-01

    The lack of sensors for some relevant state variables in fermentation processes can be coped by developing appropriate software sensors. In this work, NARX-ANN, NARMAX-ANN, NARX-SVM and NARMAX-SVM models are compared when acting as software sensors of biomass concentration for a solid substrate cultivation (SSC) process. Results show that NARMAX-SVM outperforms the other models with an SMAPE index under 9 for a 20 % amplitude noise. In addition, NARMAX models perform better than NARX models under the same noise conditions because of their better predictive capabilities as they include prediction errors as inputs. In the case of perturbation of initial conditions of the autoregressive variable, NARX models exhibited better convergence capabilities. This work also confirms that a difficult to measure variable, like biomass concentration, can be estimated on-line from easy to measure variables like CO₂ and O₂ using an adequate software sensor based on computational intelligence techniques. PMID:23429930

  12. Symposium on Machine Processing of Remotely Sensed Data, Purdue University, West Lafayette, Ind., June 29-July 1, 1976, Proceedings

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Papers are presented on the applicability of Landsat data to water management and control needs, IBIS, a geographic information system based on digital image processing and image raster datatype, and the Image Data Access Method (IDAM) for the Earth Resources Interactive Processing System. Attention is also given to the Prototype Classification and Mensuration System (PROCAMS) applied to agricultural data, the use of Landsat for water quality monitoring in North Carolina, and the analysis of geophysical remote sensing data using multivariate pattern recognition. The Illinois crop-acreage estimation experiment, the Pacific Northwest Resources Inventory Demonstration, and the effects of spatial misregistration on multispectral recognition are also considered. Individual items are announced in this issue.

  13. Copying Machine Improvement

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Manufacturer of the Model 2210 copying machine was looking for a plastic valve bushing material that could be produced by a low-cost injection molding process to replace the unsuitable valve bushing they were using. NERAC conducted a computer search of the NASA database and was able to supply Nashua Corporation with several technical reports in their area of interest. Information aided the company's development of a urethane valve bushing which solved the problem and created a dramatic reduction in unit cost.

  14. Case for a field-programmable gate array multicore hybrid machine for an image-processing application

    NASA Astrophysics Data System (ADS)

    Rakvic, Ryan N.; Ives, Robert W.; Lira, Javier; Molina, Carlos

    2011-01-01

    General purpose computer designers have recently begun adding cores to their processors in order to increase performance. For example, Intel has adopted a homogeneous quad-core processor as a base for general purpose computing. PlayStation3 (PS3) game consoles contain a multicore heterogeneous processor known as the Cell, which is designed to perform complex image processing algorithms at a high level. Can modern image-processing algorithms utilize these additional cores? On the other hand, modern advancements in configurable hardware, most notably field-programmable gate arrays (FPGAs) have created an interesting question for general purpose computer designers. Is there a reason to combine FPGAs with multicore processors to create an FPGA multicore hybrid general purpose computer? Iris matching, a repeatedly executed portion of a modern iris-recognition algorithm, is parallelized on an Intel-based homogeneous multicore Xeon system, a heterogeneous multicore Cell system, and an FPGA multicore hybrid system. Surprisingly, the cheaper PS3 slightly outperforms the Intel-based multicore on a core-for-core basis. However, both multicore systems are beaten by the FPGA multicore hybrid system by >50%.

  15. An intelligent CNC machine control system architecture

    SciTech Connect

    Miller, D.J.; Loucks, C.S.

    1996-10-01

    Intelligent, agile manufacturing relies on automated programming of digitally controlled processes. Currently, processes such as Computer Numerically Controlled (CNC) machining are difficult to automate because of highly restrictive controllers and poor software environments. It is also difficult to utilize sensors and process models for adaptive control, or to integrate machining processes with other tasks within a factory floor setting. As part of a Laboratory Directed Research and Development (LDRD) program, a CNC machine control system architecture based on object-oriented design and graphical programming has been developed to address some of these problems and to demonstrate automated agile machining applications using platform-independent software.

  16. Left ear advantage in speech-related dichotic listening is not specific to auditory processing disorder in children: A machine-learning fMRI and DTI study☆

    PubMed Central

    Schmithorst, Vincent J.; Farah, Rola; Keith, Robert W.

    2013-01-01

    Dichotic listening (DL) tests are among the most frequently included in batteries for the diagnosis of auditory processing disorders (APD) in children. A finding of atypical left ear advantage (LEA) for speech-related stimuli is often taken by clinical audiologists as an indicator for APD. However, the precise etiology of ear advantage in DL tests has been a source of debate for decades. It is uncertain whether a finding of LEA is truly indicative of a sensory processing deficit such as APD, or whether attentional or other supramodal factors may also influence ear advantage. Multivariate machine learning was used on diffusion tensor imaging (DTI) and functional MRI (fMRI) data from a cohort of children ages 7–14 referred for APD testing with LEA, and typical controls with right-ear advantage (REA). LEA was predicted by: increased axial diffusivity in the left internal capsule (sublenticular region), and decreased functional activation in the left frontal eye fields (BA 8) during words presented diotically as compared to words presented dichotically, compared to children with right-ear advantage (REA). These results indicate that both sensory and attentional deficits may be predictive of LEA, and thus a finding of LEA, while possibly due to sensory factors, is not a specific indicator of APD as it may stem from a supramodal etiology. PMID:24179844

  17. Real-time parallel implementation of Pulse-Doppler radar signal processing chain on a massively parallel machine based on multi-core DSP and Serial RapidIO interconnect

    NASA Astrophysics Data System (ADS)

    Klilou, Abdessamad; Belkouch, Said; Elleaume, Philippe; Le Gall, Philippe; Bourzeix, François; Hassani, Moha M'Rabet

    2014-12-01

    Pulse-Doppler radars require high-computing power. A massively parallel machine has been developed in this paper to implement a Pulse-Doppler radar signal processing chain in real-time fashion. The proposed machine consists of two C6678 digital signal processors (DSPs), each with eight DSP cores, interconnected with Serial RapidIO (SRIO) bus. In this study, each individual core is considered as the basic processing element; hence, the proposed parallel machine contains 16 processing elements. A straightforward model has been adopted to distribute the Pulse-Doppler radar signal processing chain. This model provides low latency, but communication inefficiency limits system performance. This paper proposes several optimizations that greatly reduce the inter-processor communication in a straightforward model and improves the parallel efficiency of the system. A use case of the Pulse-Doppler radar signal processing chain has been used to illustrate and validate the concept of the proposed mapping model. Experimental results show that the parallel efficiency of the proposed parallel machine is about 90%.

  18. Helium-3 relaxation time measurements at low temperatures for the neutron electric dipole moment (nEDM) experiment

    NASA Astrophysics Data System (ADS)

    Ye, Qiang

    The search for the existence of a nonzero neutron electric dipole moment (nEDM) has the potential to reveal new sources of T and CP violation beyond the Standard Model and may have a significant impact on our understanding of the universe. A new experiment aiming at two orders of magnitude improvement (˜ 10--28 e·cm) over the current experimental upper limit has been proposed in the United States. In the experiment, the measurement cell will be made of dTPB-dPS coated acrylic and filled with superfluid 4He at ˜300-500 mK. The measurement of the neutron precession frequency will rely on the spin-dependence of the cross section of the nuclear reaction between polarized neutrons and 3He atoms: n⃗+H3 ⃗e → p + t + 764 keV. Polarized 3He will also be used as a comagnetometer based on the nuclear magnetic resonance technique. The 3He polarization needs to have sufficiently long relaxation time so that little polarization is lost during the measurement period in order to achieve the proposed sensitivity. Understanding the relaxation mechanism of 3He polarization in the measurement cell under the nEDM experimental conditions and maintaining 3He polarization is crucial for the experiment. With the presence of superfluid 4He, 3He relaxation time measurements in a dTPB-dPS coated cylindrical acrylic cell at the temperature of 1.9 K and ˜400 mK have been performed at the Triangle University Nuclear Laboratory (TUNL) on the campus of Duke University. The extracted depolarization probabilities of polarized 3He on the cell surface are on the order of (1 -- 2) x 10--7 at 1.9 K and ˜ 4.7 x 10--7 at ˜400 mK. The extrapolated relaxation time of polarized 3He in the nEDM cell geometry is ˜ 4870 seconds at ˜400 mK, which is sufficiently long for the nEDM experiment and further improvements are anticipated.

  19. Machine musicianship

    NASA Astrophysics Data System (ADS)

    Rowe, Robert

    2002-05-01

    The training of musicians begins by teaching basic musical concepts, a collection of knowledge commonly known as musicianship. Computer programs designed to implement musical skills (e.g., to make sense of what they hear, perform music expressively, or compose convincing pieces) can similarly benefit from access to a fundamental level of musicianship. Recent research in music cognition, artificial intelligence, and music theory has produced a repertoire of techniques that can make the behavior of computer programs more musical. Many of these were presented in a recently published book/CD-ROM entitled Machine Musicianship. For use in interactive music systems, we are interested in those which are fast enough to run in real time and that need only make reference to the material as it appears in sequence. This talk will review several applications that are able to identify the tonal center of musical material during performance. Beyond this specific task, the design of real-time algorithmic listening through the concurrent operation of several connected analyzers is examined. The presentation includes discussion of a library of C++ objects that can be combined to perform interactive listening and a demonstration of their capability.

  20. Machine wanting.

    PubMed

    McShea, Daniel W

    2013-12-01

    Wants, preferences, and cares are physical things or events, not ideas or propositions, and therefore no chain of pure logic can conclude with a want, preference, or care. It follows that no pure-logic machine will ever want, prefer, or care. And its behavior will never be driven in the way that deliberate human behavior is driven, in other words, it will not be motivated or goal directed. Therefore, if we want to simulate human-style interactions with the world, we will need to first understand the physical structure of goal-directed systems. I argue that all such systems share a common nested structure, consisting of a smaller entity that moves within and is driven by a larger field that contains it. In such systems, the smaller contained entity is directed by the field, but also moves to some degree independently of it, allowing the entity to deviate and return, to show the plasticity and persistence that is characteristic of goal direction. If all this is right, then human want-driven behavior probably involves a behavior-generating mechanism that is contained within a neural field of some kind. In principle, for goal directedness generally, the containment can be virtual, raising the possibility that want-driven behavior could be simulated in standard computational systems. But there are also reasons to believe that goal-direction works better when containment is also physical, suggesting that a new kind of hardware may be necessary. PMID:23792091

  1. From ergonomics to design specifications: contributions to the design of a processing machine in a tire company.

    PubMed

    Moraes, A S P; Arezes, P M; Vasconcelos, R

    2012-01-01

    The development of ergonomics' recommendations, guidelines and standards are attempts to promote the integration of ergonomics into industrial contexts. Such developments result from several sources and professionals and represent the effort that has been done to develop healthier and safer work environments. However, the availability of large amount of data and documents regarding ergonomics does not guarantee their applicability. The main goal of this paper is to use a specific case to demonstrate how ergonomics criteria were developed in order to contribute to the design of workplaces. Based on the obtained results from research undertaken in a tire company, it was observed that the ergonomics criteria should be presented as design specifications in order to be used by engineers and designers. In conclusion, it is observed that the multiple constraint environment impeded the appliance of the ergonomics criteria. It was also observed that the knowledge on technical design and the acquaintance with ergonomic standards, the level of integration in the design team, and the ability to communicate with workers and other technical staff have paramount importance in integrating ergonomics criteria into the design process. PMID:22316781

  2. Altered neural correlates of reward and loss processing during simulated slot-machine fMRI in pathological gambling and cocaine dependence☆

    PubMed Central

    Worhunsky, Patrick D.; Malison, Robert T.; Rogers, Robert D.; Potenza, Marc N.

    2014-01-01

    Background Individuals with gambling or substance-use disorders exhibit similar functional alterations in reward circuitry suggestive of a shared underlying vulnerability in addictive disorders. Additional research into common and unique alterations in reward-processing in substance-related and non-substance-related addictions may identify neural factors that could be targeted in treatment development for these disorders. Methods To investigate contextual reward-processing in pathological gambling, a slot-machine fMRI task was performed by three groups (with pathological gambling, cocaine dependence and neither disorder; N=24 each) to determine the extent to which two groups with addictions (non-substance-related and substance-related) showed similarities and differences with respect to each other and a non-addicted group during anticipatory periods and following the delivery of winning, losing and ‘near-miss’ outcomes. Results Individuals with pathological gambling or cocaine dependence compared to those with neither disorder exhibited exaggerated anticipatory activity in mesolimbic and ventrocortical regions, with pathological-gambling participants displaying greater positive possible-reward anticipation and cocaine-dependent participants displaying more negative certain-loss anticipation. Neither clinical sample exhibited medial frontal or striatal responses that were observed following near-miss outcomes in healthy comparison participants. Conclusions Alterations in anticipatory processing may be sensitive to the valence of rewards and content-disorder-specific. Common and unique findings in pathological gambling and cocaine dependence with respect to anticipatory reward and near-miss loss processing suggest shared and unique elements that might be targeted through behavioral or pharmacological interventions in the treatment of addictions. PMID:25448081

  3. Vibration assisted femtosecond laser machining on metal

    NASA Astrophysics Data System (ADS)

    Park, Jung-Kyu; Yoon, Ji-Wook; Cho, Sung-Hak

    2012-06-01

    We demonstrate a novel approach to improve laser machining quality on metals by vibrating the optical objective lens with a frequency (of 500 Hz) and various displacements (0-16.5 μm) during a femtosecond laser machining process. The laser used in this experiment is an amplified Ti:sapphire fs laser system that generates 100 fs pulses having an energy of 3.5 mJ/pulse with a 5 kHz repetition rate at a central wavelength of 790 nm. It is found that both the wall surface finish of the machined structures and the aspect ratio obtained using the frequency vibration assisted laser machining are improved, compared to those derived via laser machining without vibration assistance. This is the first report of low frequency vibration of an optical objective lens in the femtosecond laser machining process being exploited to obtain significantly improved surface roughness of machined side walls and increased aspect ratios.

  4. Biosleeve Human-Machine Interface

    NASA Technical Reports Server (NTRS)

    Assad, Christopher (Inventor)

    2016-01-01

    Systems and methods for sensing human muscle action and gestures in order to control machines or robotic devices are disclosed. One exemplary system employs a tight fitting sleeve worn on a user arm and including a plurality of electromyography (EMG) sensors and at least one inertial measurement unit (IMU). Power, signal processing, and communications electronics may be built into the sleeve and control data may be transmitted wirelessly to the controlled machine or robotic device.

  5. Autonomous agent for on-machine acceptance of machined components

    NASA Astrophysics Data System (ADS)

    Pancerella, Carmen M.; Hazelton, Andrew J.; Frost, H. R.

    1995-11-01

    In recent years, manufacturers of high precision mechanical parts have been required to produce increasingly complex designs, in smaller lot sizes, with improved quality. These requirements demand lower process costs, shorter development cycles and more accurate manufacturing technologies. To meet these demands, manufacturers are attempting to both improve process quality and provide better CAD/CAM integration. The technique of on- machine acceptance provides one mechanisms for improving the part inspection and verification process. This approach allows one machine and one process capability model to be used for both fabrication and inspection, reducing capital cost and overall cycle time. However, the on-machine acceptance technique possesses greater potential than as simply an alternative mechanism for verifying part geometry. If the inspection capability information generated by on-machine acceptance processes can be made available to designers, it can be used to create a design-for-inspectability environment and help realize the benefits of concurrent engineering. This paper proposes a novel architecture which integrates on-machine acceptance with an agent-based concurrent design environment, for reducing both the cost and production time for high quality, small lot size, mechanical parts. This work has focused on the production of stainless steel pressure vessels at the Integrated Manufacturing Technology Laboratory manufacturing cell, located at Sandia National Laboratories, California.

  6. RISMA: A Rule-based Interval State Machine Algorithm for Alerts Generation, Performance Analysis and Monitoring Real-Time Data Processing

    NASA Astrophysics Data System (ADS)

    Laban, Shaban; El-Desouky, Aly

    2013-04-01

    The monitoring of real-time systems is a challenging and complicated process. So, there is a continuous need to improve the monitoring process through the use of new intelligent techniques and algorithms for detecting exceptions, anomalous behaviours and generating the necessary alerts during the workflow monitoring of such systems. The interval-based or period-based theorems have been discussed, analysed, and used by many researches in Artificial Intelligence (AI), philosophy, and linguistics. As explained by Allen, there are 13 relations between any two intervals. Also, there have also been many studies of interval-based temporal reasoning and logics over the past decades. Interval-based theorems can be used for monitoring real-time interval-based data processing. However, increasing the number of processed intervals makes the implementation of such theorems a complex and time consuming process as the relationships between such intervals are increasing exponentially. To overcome the previous problem, this paper presents a Rule-based Interval State Machine Algorithm (RISMA) for processing, monitoring, and analysing the behaviour of interval-based data, received from real-time sensors. The proposed intelligent algorithm uses the Interval State Machine (ISM) approach to model any number of interval-based data into well-defined states as well as inferring them. An interval-based state transition model and methodology are presented to identify the relationships between the different states of the proposed algorithm. By using such model, the unlimited number of relationships between similar large numbers of intervals can be reduced to only 18 direct relationships using the proposed well-defined states. For testing the proposed algorithm, necessary inference rules and code have been designed and applied to the continuous data received in near real-time from the stations of International Monitoring System (IMS) by the International Data Centre (IDC) of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). The CLIPS expert system shell has been used as the main rule engine for implementing the algorithm rules. Python programming language and the module "PyCLIPS" are used for building the necessary code for algorithm implementation. More than 1.7 million intervals constitute the Concise List of Frames (CLF) from 20 different seismic stations have been used for evaluating the proposed algorithm and evaluating stations behaviour and performance. The initial results showed that proposed algorithm can help in better understanding of the operation and performance of those stations. Different important information, such as alerts and some station performance parameters, can be derived from the proposed algorithm. For IMS interval-based data and at any period of time it is possible to analyze station behavior, determine the missing data, generate necessary alerts, and to measure some of station performance attributes. The details of the proposed algorithm, methodology, implementation, experimental results, advantages, and limitations of this research are presented. Finally, future directions and recommendations are discussed.

  7. Upgrading the capabilities of existing machine tools for precision machining

    SciTech Connect

    Barkman, W.E.

    1982-05-01

    A number of two-axis turning machines at the Oak Ridge Y-12 Plant have undergone upgrading as a means of meeting the needs for parts with tolerances that were more restrictive than the capability of the basic machine. The level of upgrading has ranged from changing a single machine characteristic to doing a complete overhaul of the slides, drives, spindle, and control system. The features available for the up-grading process include: tool setters, air bearing spindles and slides, pressurized oil bearing slides, electric dc torque motor drives, linear motor slide drives, eddy current spindle drives, laser feedback, vibration-isolation machine platforms, and computer numerical control (CNC) systems. Actual case histories are presented which show the levels of performance achieved with the various modifications. A discussion of the advantages and disadvantages of the various options is included.

  8. The effect of electric discharge machined notches on the fracture toughness of several structural alloys

    SciTech Connect

    Joyce, J.A.; Link, R.E.

    1993-09-01

    Recent computational studies of the stress and strain fields at the tip of very sharp notches have shown that the stress and strain fields are very weakly dependent on the initial geometry of the notch once the notch has been blunted to a radius that is 6 to 10 times the initial root radius. It follows that if the fracture toughness of a material is sufficiently high so that fracture initiation does not occur in a specimen until the crack-tip opening displacement (CTOD) reaches a value from 6 to 10 times the size of the initial notch tip diameter, then the fracture toughness will be independent of whether a fatigue crack or a machined notch served as the initial crack. In this experimental program the fracture toughness (J{sub Ic} and J resistance (J-R) curve, and CTOD) for several structure alloys was measured using specimens with conventional fatigue cracks and with EDM machined notches. The results of this program have shown, in fact, that most structural materials do not achieve initiation CTOD values on the order of 6 to 10 times the radius of even the smallest EDM notch tip presently achievable. It is found furthermore that tougher materials do not seem to be less dependent on the type of notch tip present. Some materials are shown to be much more dependent on the type of notch tip used, but no simple pattern is found that relates this observed dependence to the material strength toughness, or strain hardening rate.

  9. Calibration of catalyst temperature in automotive engines over coldstart operation in the presence of different random noises and uncertainty: Implementation of generalized Gaussian process regression machine

    NASA Astrophysics Data System (ADS)

    Azad, Nasser L.; Mozaffari, Ahmad

    2015-12-01

    The main scope of the current study is to develop a systematic stochastic model to capture the undesired uncertainty and random noises on the key parameters affecting the catalyst temperature over the coldstart operation of automotive engine systems. In the recent years, a number of articles have been published which aim at the modeling and analysis of automotive engines' behavior during coldstart operations by using regression modeling methods. Regarding highly nonlinear and uncertain nature of the coldstart operation, calibration of the engine system's variables, for instance the catalyst temperature, is deemed to be an intricate task, and it is unlikely to develop an exact physics-based nonlinear model. This encourages automotive engineers to take advantage of knowledge-based modeling tools and regression approaches. However, there exist rare reports which propose an efficient tool for coping with the uncertainty associated with the collected database. Here, the authors introduce a random noise to experimentally derived data and simulate an uncertain database as a representative of the engine system's behavior over coldstart operations. Then, by using a Gaussian process regression machine (GPRM), a reliable model is used for the sake of analysis of the engine's behavior. The simulation results attest the efficacy of GPRM for the considered case study. The research outcomes confirm that it is possible to develop a practical calibration tool which can be reliably used for modeling the catalyst temperature.

  10. Evolution of replication machines.

    PubMed

    Yao, Nina Y; O'Donnell, Mike E

    2016-01-01

    The machines that decode and regulate genetic information require the translation, transcription and replication pathways essential to all living cells. Thus, it might be expected that all cells share the same basic machinery for these pathways that were inherited from the primordial ancestor cell from which they evolved. A clear example of this is found in the translation machinery that converts RNA sequence to protein. The translation process requires numerous structural and catalytic RNAs and proteins, the central factors of which are homologous in all three domains of life, bacteria, archaea and eukarya. Likewise, the central actor in transcription, RNA polymerase, shows homology among the catalytic subunits in bacteria, archaea and eukarya. In contrast, while some "gears" of the genome replication machinery are homologous in all domains of life, most components of the replication machine appear to be unrelated between bacteria and those of archaea and eukarya. This review will compare and contrast the central proteins of the "replisome" machines that duplicate DNA in bacteria, archaea and eukarya, with an eye to understanding the issues surrounding the evolution of the DNA replication apparatus. PMID:27160337

  11. Universal Memcomputing Machines.

    PubMed

    Traversa, Fabio Lorenzo; Di Ventra, Massimiliano

    2015-11-01

    We introduce the notion of universal memcomputing machines (UMMs): a class of brain-inspired general-purpose computing machines based on systems with memory, whereby processing and storing of information occur on the same physical location. We analytically prove that the memory properties of UMMs endow them with universal computing power (they are Turing-complete), intrinsic parallelism, functional polymorphism, and information overhead, namely, their collective states can support exponential data compression directly in memory. We also demonstrate that a UMM has the same computational power as a nondeterministic Turing machine, namely, it can solve nondeterministic polynomial (NP)-complete problems in polynomial time. However, by virtue of its information overhead, a UMM needs only an amount of memory cells (memprocessors) that grows polynomially with the problem size. As an example, we provide the polynomial-time solution of the subset-sum problem and a simple hardware implementation of the same. Even though these results do not prove the statement NP = P within the Turing paradigm, the practical realization of these UMMs would represent a paradigm shift from the present von Neumann architectures, bringing us closer to brain-like neural computation. PMID:25667360

  12. Machine Learning in Medicine.

    PubMed

    Deo, Rahul C

    2015-11-17

    Spurred by advances in processing power, memory, storage, and an unprecedented wealth of data, computers are being asked to tackle increasingly complex learning tasks, often with astonishing success. Computers have now mastered a popular variant of poker, learned the laws of physics from experimental data, and become experts in video games - tasks that would have been deemed impossible not too long ago. In parallel, the number of companies centered on applying complex data analysis to varying industries has exploded, and it is thus unsurprising that some analytic companies are turning attention to problems in health care. The purpose of this review is to explore what problems in medicine might benefit from such learning approaches and use examples from the literature to introduce basic concepts in machine learning. It is important to note that seemingly large enough medical data sets and adequate learning algorithms have been available for many decades, and yet, although there are thousands of papers applying machine learning algorithms to medical data, very few have contributed meaningfully to clinical care. This lack of impact stands in stark contrast to the enormous relevance of machine learning to many other industries. Thus, part of my effort will be to identify what obstacles there may be to changing the practice of medicine through statistical learning approaches, and discuss how these might be overcome. PMID:26572668

  13. From human-machine interaction to human-machine cooperation.

    PubMed

    Hoc, J M

    2000-07-01

    Since the 1960s, the rapid growth of information systems has led to the wide development of research on human-computer interaction (HCI) that aims at the designing of human-computer interfaces presenting ergonomic properties, such as friendliness, usability, transparency, etc. Various work situations have been covered--clerical work, computer programming, design, etc. However, they were mainly static in the sense that the user fully controls the computer. More recently, public and private organizations have engaged themselves in the enterprise of managing more and more complex and coupled systems by the means of automation. Modern machines not only process information, but also act on dynamic situations as humans have done in the past, managing stock exchange, industrial plants, aircraft, etc. These dynamic situations are not fully controlled and are affected by uncertain factors. Hence, degrees of freedom must be maintained to allow the humans and the machine to adapt to unforeseen contingencies. A human-machine cooperation (HMC) approach is necessary to address the new stakes introduced by this trend. This paper describes the possible improvement of HCI by HMC, the need for a new conception of function allocation between humans and machines, and the main problems encountered within the new forms of human-machine relationship. It proposes a conceptual framework to study HMC from a cognitive point of view in highly dynamic situations like aircraft piloting or air-traffic control, and concludes on the design of 'cooperative' machines. PMID:10929820

  14. Humanizing machines: Anthropomorphization of slot machines increases gambling.

    PubMed

    Riva, Paolo; Sacchi, Simona; Brambilla, Marco

    2015-12-01

    Do people gamble more on slot machines if they think that they are playing against humanlike minds rather than mathematical algorithms? Research has shown that people have a strong cognitive tendency to imbue humanlike mental states to nonhuman entities (i.e., anthropomorphism). The present research tested whether anthropomorphizing slot machines would increase gambling. Four studies manipulated slot machine anthropomorphization and found that exposing people to an anthropomorphized description of a slot machine increased gambling behavior and reduced gambling outcomes. Such findings emerged using tasks that focused on gambling behavior (Studies 1 to 3) as well as in experimental paradigms that included gambling outcomes (Studies 2 to 4). We found that gambling outcomes decrease because participants primed with the anthropomorphic slot machine gambled more (Study 4). Furthermore, we found that high-arousal positive emotions (e.g., feeling excited) played a role in the effect of anthropomorphism on gambling behavior (Studies 3 and 4). Our research indicates that the psychological process of gambling-machine anthropomorphism can be advantageous for the gaming industry; however, this may come at great expense for gamblers' (and their families') economic resources and psychological well-being. PMID:26322589

  15. Multicutter machining of compound parametric surfaces

    NASA Astrophysics Data System (ADS)

    Hatna, Abdelmadjid; Grieve, R. J.; Broomhead, P.

    2000-10-01

    Parametric free forms are used in industries as disparate as footwear, toys, sporting goods, ceramics, digital content creation, and conceptual design. Optimizing tool path patterns and minimizing the total machining time is a primordial issue in numerically controlled (NC) machining of free form surfaces. We demonstrate in the present work that multi-cutter machining can achieve as much as 60% reduction in total machining time for compound sculptured surfaces. The given approach is based upon the pre-processing as opposed to the usual post-processing of surfaces for the detection and removal of interference followed by precise tracking of unmachined areas.

  16. Development of a Machining Tester for Two Dimensional Machining Test under External Hydrostatic Pressure

    NASA Astrophysics Data System (ADS)

    Yoshino, Masahiko; Higashi, Eiji; Kawade, Kousuke

    This paper reports on a new machining device developed for experimental study on machining property of hard-brittle materials under external hydrostatic pressure. A new machining device was developed for two dimensional machining tests as well as in situ observation of a machining process by an optical microscope under hydrostatic pressure up to 400MPa. The device consists of four parts; a high pressure vessel, a pump system, a machining device installed in the chamber and an optical microscope. Detail of structure of the device is reported in the paper. Two dimensional machining tests of a soda glass plate were conducted using the device under four levels of pressure. Results of the machining tests is also reported.

  17. CENTRIFUGAL CASTING MACHINE

    DOEpatents

    Shuck, A.B.

    1958-04-01

    A device is described that is specifically designed to cast uraniumn fuel rods in a vacuunn, in order to obtain flawless, nonoxidized castings which subsequently require a maximum of machining or wastage of the expensive processed material. A chamber surrounded with heating elements is connected to the molds, and the entire apparatus is housed in an airtight container. A charge of uranium is placed in the chamber, heated, then is allowed to flow into the molds While being rotated. Water circulating through passages in the molds chills the casting to form a fine grained fuel rod in nearly finished form.

  18. An in situ probe for on-line monitoring of cell density and viability on the basis of dark field microscopy in conjunction with image processing and supervised machine learning.

    PubMed

    Wei, Ning; You, Jia; Friehs, Karl; Flaschel, Erwin; Nattkemper, Tim Wilhelm

    2007-08-15

    Fermentation industries would benefit from on-line monitoring of important parameters describing cell growth such as cell density and viability during fermentation processes. For this purpose, an in situ probe has been developed, which utilizes a dark field illumination unit to obtain high contrast images with an integrated CCD camera. To test the probe, brewer's yeast Saccharomyces cerevisiae is chosen as the target microorganism. Images of the yeast cells in the bioreactors are captured, processed, and analyzed automatically by means of mechatronics, image processing, and machine learning. Two support vector machine based classifiers are used for separating cells from background, and for distinguishing live from dead cells afterwards. The evaluation of the in situ experiments showed strong correlation between results obtained by the probe and those by widely accepted standard methods. Thus, the in situ probe has been proved to be a feasible device for on-line monitoring of both cell density and viability with high accuracy and stability. PMID:17274069

  19. Progress on Electrode Designs and Tests to Generate High Electric Field in Superfluid Liquid Helium-4 for the SNS nEDM Experiment

    NASA Astrophysics Data System (ADS)

    Wei, Wanchun; Beck, Douglas; Cianciolo, Vince; Clayton, Steven; Crawford, Christopher; Currie, Scott; Griffith, William; Ito, Takeyasu; Ramsey, John; Roberts, Amy; Schmid, Richardo; Seidel, George; Wagner, Daniel; Williamson, Steven; Yao, Weijun; SNS nEDM Collaboration

    2015-10-01

    The SNS nEDM experiment is aiming to search for the neutron electric dipole moment (EDM) with ultracold neutrons (UCNs) stored in superfluid liquid helium-4 at the Spallation Neutron Source (SNS) in Oak Ridge National Laboratory, with a goal sensitivity of 3×10-28e-cm, an improvement of two orders of magnitude over the current limit. To achieve the goal sensitivity of the EDM searches,it relies on the stable application of a 75 kV/cm electric field across the UCN storage space without breakdowns in superfluid liquid helium-4. The electrode designs and tests on various geometries and coating materials are undergoing. The high voltage tests in superfluid helium-4 are performed in a specially-designed apparatus at temperatures as low as 0.4 K and pressures between saturated vapor pressure (SVP) of liquid helium and 1 atm. These tests would help in a better understanding of the electric breakdown phenomenon in liquid helium-4. In this talk, we will present the latest progress on electrode designs and tests,and their implications of findings that affect the design of the SNS nEDM experiment.

  20. Progress on Tests of Electric Breakdown of Superfluid Liquid Helium-4 in High Electric Field for the SNS nEDM Experiment

    NASA Astrophysics Data System (ADS)

    Wei, Wanchun; Beck, Douglas; Cianciolo, Vince; Clayton, Steven; Crawford, Christopher; Currie, Scott; Griffith, William; Ito, Takeyasu; Ramsey, John; Roberts, Amy; Schmid, Richardo; Seidel, George; Wagner, Daniel; Williamson, Steven; Yao, Weijun; SNS nEDM Collaboration

    2015-04-01

    The SNS nEDM experiment is a collaborative project under development, which aims to search for the neutron electric dipole moment (EDM) with ultracold neutrons (UCNs) stored in superfluid liquid helium-4 at the Spallation Neutron Source (SNS) in Oak Ridge National Laboratory. In general, the ultimate sensitivity of the EDM searches linearly depends on the strength of the applied electric field across the volume of superfluid liquid helium-4 in the UCN storage space. Our goal is to achieve an electric field with strength of 75 kV/cm. However, the phenomenon of electric breakdown in liquid helium-4 is poorly understood in the available literatures. We, therefore, have developed an apparatus to study it at temperatures as low as 0.4 K and pressures between saturated vapor pressure (SVP) of liquid helium and 1 atm. In this talk, we will present the latest progress on the tests of the electric breakdown of superfluid liquid helium-4 and its implications of findings that affect the design of the SNS nEDM experiment.

  1. Building and simulating protein machines

    NASA Astrophysics Data System (ADS)

    Katebi, Ataur Rahim

    Glycolysis is a central metabolic pathway, present in almost all organisms, that produces energy. The pathway has been extensively investigated by biochemists. There is a significant body of structural and biochemical information about this pathway. The complete pathway is a ten step process. At each step, a specific chemical reaction is catalyzed by a specific enzyme. Fructose bisphosphate aldolase (FBA) and triosephosphate isomerase (TIM) catalyze the fourth and the fifth steps on the pathway. This thesis investigates the possible substrate transfer mechanism between FBA and TIM. FBA cleaves its substrate, the six-carbon fructose-1,6-bisphosphate (FBP), into two three-carbon products -- glyceraldehydes 3-phosphate (GAP) and dihydroxy acetone phosphate (DHAP). One component of these two products, DHAP, is the substrate for TIM and the other component GAP goes directly to GAPDH, the subsequent enzyme on the pathway. TIM converts DHAP to GAP and delivers the product to GAPDH. I employ Elastic Network Models (ENM) to investigate the mechanistic and dynamic aspects of the functionality of FBA and TIM enzymes -- (1) the effects of the oligomerization of these two enzymes on their functional dynamics and the coordination of the individual protein's structural components along the functional region; and (2) the mechanistic synchrony of these two protein machines that may enable them to operate in a coordinated fashion as a conjugate machine -- transferring the product from FBA as substrate to TIM. A macromolecular machine comprised of FBA and TIM will facilitate the substrate catalysis mechanism and the product flow between FBA and TIM. Such a machine could be used as a functional unit in building a larger a machine for the structural modeling of the whole glycolysis pathway. Building such machines for the glycolysis pathway may reveal the interplay of the enzymes as a complete machine. Also the methods and insights developed from the efforts to build such large machines could be applied to build macromolecular structures for other biologically important clusters of interacting enzymes centered around individual metabolic pathways.

  2. Estimation of breast percent density in raw and processed full field digital mammography images via adaptive fuzzy c-means clustering and support vector machine segmentation

    SciTech Connect

    Keller, Brad M.; Nathan, Diane L.; Wang Yan; Zheng Yuanjie; Gee, James C.; Conant, Emily F.; Kontos, Despina

    2012-08-15

    Purpose: The amount of fibroglandular tissue content in the breast as estimated mammographically, commonly referred to as breast percent density (PD%), is one of the most significant risk factors for developing breast cancer. Approaches to quantify breast density commonly focus on either semiautomated methods or visual assessment, both of which are highly subjective. Furthermore, most studies published to date investigating computer-aided assessment of breast PD% have been performed using digitized screen-film mammograms, while digital mammography is increasingly replacing screen-film mammography in breast cancer screening protocols. Digital mammography imaging generates two types of images for analysis, raw (i.e., 'FOR PROCESSING') and vendor postprocessed (i.e., 'FOR PRESENTATION'), of which postprocessed images are commonly used in clinical practice. Development of an algorithm which effectively estimates breast PD% in both raw and postprocessed digital mammography images would be beneficial in terms of direct clinical application and retrospective analysis. Methods: This work proposes a new algorithm for fully automated quantification of breast PD% based on adaptive multiclass fuzzy c-means (FCM) clustering and support vector machine (SVM) classification, optimized for the imaging characteristics of both raw and processed digital mammography images as well as for individual patient and image characteristics. Our algorithm first delineates the breast region within the mammogram via an automated thresholding scheme to identify background air followed by a straight line Hough transform to extract the pectoral muscle region. The algorithm then applies adaptive FCM clustering based on an optimal number of clusters derived from image properties of the specific mammogram to subdivide the breast into regions of similar gray-level intensity. Finally, a SVM classifier is trained to identify which clusters within the breast tissue are likely fibroglandular, which are then aggregated into a final dense tissue segmentation that is used to compute breast PD%. Our method is validated on a group of 81 women for whom bilateral, mediolateral oblique, raw and processed screening digital mammograms were available, and agreement is assessed with both continuous and categorical density estimates made by a trained breast-imaging radiologist. Results: Strong association between algorithm-estimated and radiologist-provided breast PD% was detected for both raw (r= 0.82, p < 0.001) and processed (r= 0.85, p < 0.001) digital mammograms on a per-breast basis. Stronger agreement was found when overall breast density was assessed on a per-woman basis for both raw (r= 0.85, p < 0.001) and processed (0.89, p < 0.001) mammograms. Strong agreement between categorical density estimates was also seen (weighted Cohen's {kappa}{>=} 0.79). Repeated measures analysis of variance demonstrated no statistically significant differences between the PD% estimates (p > 0.1) due to either presentation of the image (raw vs processed) or method of PD% assessment (radiologist vs algorithm). Conclusions: The proposed fully automated algorithm was successful in estimating breast percent density from both raw and processed digital mammographic images. Accurate assessment of a woman's breast density is critical in order for the estimate to be incorporated into risk assessment models. These results show promise for the clinical application of the algorithm in quantifying breast density in a repeatable manner, both at time of imaging as well as in retrospective studies.

  3. DREAMS: a payload on-board the ExoMars EDM Schiaparelli for the characterization of Martian environment during the statistical dust storm season

    NASA Astrophysics Data System (ADS)

    Molfese, Cesare; Esposito, Francesca; Debei, Stefano; Bettanini, Carlo; Arruego Rodríguez, Ignacio; Colombatti, Giacomo; Harri, Ari-Matty.; Montmessin, Franck; Wilson, Colin; Aboudan, Alessio; Mugnuolo, Raffaele; Pirrotta, Simone; Marchetti, Ernesto; Witasse, Olivier

    2015-04-01

    F. Esposito1, S. Debei2, C. Bettanini2, C. Molfese1, I. Arruego Rodríguez3, G. Colombatti2, A-M. Harri4, F. Montmessin5, C. Wilson6, A. Aboudan2, S. Abbaki5, V. Apestigue3, G. Bellucci7, J-J. Berthelier5, J. R. Brucato8, S. B. Calcutt6, F. Cortecchia1, F. Cucciarrè2, G. Di Achille1, F. Ferri2, F. Forget9, E. Friso2, M. Genzer4, P. Gilbert5, H. Haukka4, J. J. Jiménez3, S. Jiménez10, J-L. Josset11, O. Karatekin12, G. Landis13, R. Lorenz14, J. Martinez3, L. Marty1, V. Mennella1, D. Möhlmann15, D. Moirin5, R. Molinaro1, E. Palomba7, M. Patel16, J-P. Pommereau5, C.I. Popa1, S. Rafkin17, P. Rannou18, N.O. Renno19, P. Schipani1, W. Schmidt4, E. Segato2, S. Silvestro1, F. Simoes20, A. Spiga9, F. Valero21, L. Vázquez21, F. Vivat5, O. Witasse22, R. Mugnuolo23, S. Pirrotta23, E.Marchetti23 1INAF - Osservatorio Astronomico di Capodimonte, Napoli, Italy, 2CISAS - Università degli Studi di Padova, Padova, Italy, 3INTA, Spain, 4Finnish Meteorological Institute (FMI),Helsinki, Finland, 5LATMOS - CNRS/UVSQ/IPSL, France, 6Oxford University, Oxford, United Kingdom, 7INAF - Istituto di Fisica dello Spazio Interplanetario (IFSI), 8INAF-Osservatorio Astrofisico di Arcetri, 9CNRS, LMD, France, 10Universidad Politécnica de Madrid, Spain, 11Space Exploration Institute, Switzerland, 12Royal Observatory of Belgium,Belgium, 13NASA, GRC, USA, 14JHU Applied Physics Lab (JHU-APL), USA, 15DLR PF Leitungsbereich, Berlin, Germany, 16Open University, UK, 17SwRL, Switzerland, 18GSMA, France, 19University of Michigan, USA, 20NASA, GSFC, USA, 21Universidad Complutense de Madrid (UCM), Spain, 22ESA-ESTEC, Noordwijk, The Netherlands, 23Italian Space Agency, Italy DREAMS (Dust characterization, Risk assessment and Environment Analyzer on the Martian Surface) package is an integrated multi-sensor scientific payload dedicated to characterizing the landing site environment in dusty conditions. It will measure pressure, wind speed and direction, relative humidity, temperature, the solar irradiance, the dust opacity, and the atmospheric electric properties close to the surface of Mars. It will fly in January 2016 on-board the Schiaparelli Entry, Descent and landing Demonstrator Module (EDM) of the ExoMars space mission. It is foreseen to land on Mars in late October 2016 during the statistical dust storm season. Therefore, DREAMS might have the unique chance to make scientific measurements to characterize the Martian environment in a dusty scenario also performing the first ever measurements of atmospheric electric field on Mars. The relationship between the process of dust entrainment in the atmosphere during dust events and the enhancement of atmospheric electric field has been widely studied in an intense field test campaign in the Sahara desert. In order to better characterize this physical process, we performed atmospheric and environmental measurements comparable to those that DREAMS will acquire on Mars. Preliminary results will be discussed. DREAMS is in a high development state. A first model has been delivered to ESA and has been integrated in the EDM Flight Model. Integration tests are on-going. The DREAMS Flight Model will be delivered at the end of March this year.

  4. Interaction with Machine Improvisation

    NASA Astrophysics Data System (ADS)

    Assayag, Gerard; Bloch, George; Cont, Arshia; Dubnov, Shlomo

    We describe two multi-agent architectures for an improvisation oriented musician-machine interaction systems that learn in real time from human performers. The improvisation kernel is based on sequence modeling and statistical learning. We present two frameworks of interaction with this kernel. In the first, the stylistic interaction is guided by a human operator in front of an interactive computer environment. In the second framework, the stylistic interaction is delegated to machine intelligence and therefore, knowledge propagation and decision are taken care of by the computer alone. The first framework involves a hybrid architecture using two popular composition/performance environments, Max and OpenMusic, that are put to work and communicate together, each one handling the process at a different time/memory scale. The second framework shares the same representational schemes with the first but uses an Active Learning architecture based on collaborative, competitive and memory-based learning to handle stylistic interactions. Both systems are capable of processing real-time audio/video as well as MIDI. After discussing the general cognitive background of improvisation practices, the statistical modelling tools and the concurrent agent architecture are presented. Then, an Active Learning scheme is described and considered in terms of using different improvisation regimes for improvisation planning. Finally, we provide more details about the different system implementations and describe several performances with the system.

  5. Hard Machinable Machining of Cobalt Super Alloys

    NASA Astrophysics Data System (ADS)

    ?ep, Robert; Jansek, Adam; Petr?, Jana; ?epov, Lenka; Sadlek, Marek; Kratochvl, Ji?

    2012-12-01

    The article deals with difficult-to-machine cobalt super alloys. The main aim is to test the basic properties of cobalt super alloys and propose suitable cutting materials and machining parameters under the designation 188 when machining. Although the development of technology in chipless machining such as moulding, precision casting and other manufacturing methods continues to advance, machining is still the leading choice for piece production, typical for energy and chemical engineering. Nowadays, super alloys are commonly used in turbine engines in regions that are subject to high temperatures, which require high strength, high temperature resistance, phase stability, as well as corrosion or oxidation resistance.

  6. Men and Machines: A Study of the Applications of Mechanisation to Library Processes and of the Effects on Staff and Library Users.

    ERIC Educational Resources Information Center

    Pickup, Peter W. H., Ed.

    The four papers presented at this weekend school are: (1) "The Effect of the Computer on Libraries" by J. D. Dews; (2) "Machines in a Rural Library Service" by O. S. Newman; (3) "The Education of Libraries in an Age of Mechanization" by D. E. Davidson and (4) "People, Programmes and Problems" by B. J. Perry. (MF)

  7. Women, Men, and Machines.

    ERIC Educational Resources Information Center

    Form, William; McMillen, David Byron

    1983-01-01

    Data from the first national study of technological change show that proportionately more women than men operate machines, are more exposed to machines that have alienating effects, and suffer more from the negative effects of technological change. (Author/SSH)

  8. Stirling machine operating experience

    NASA Technical Reports Server (NTRS)

    Ross, Brad; Dudenhoefer, James E.

    1991-01-01

    Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that Stirling machines are capable of reliable and lengthy lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and were not expected to operate for any lengthy period of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered.

  9. Tube Alinement for Machining

    NASA Technical Reports Server (NTRS)

    Garcia, J.

    1984-01-01

    Tool with stepped shoulders alines tubes for machining in preparation for welding. Alinement with machine tool axis accurate to within 5 mils (0.13mm) and completed much faster than visual setup by machinist.

  10. On-machine dimensional verification. Final report

    SciTech Connect

    Rendulic, W.

    1993-08-01

    General technology for automating in-process verification of machined products has been studied and implemented on a variety of machines and products at AlliedSignal Inc., Kansas City Division (KCD). Tests have been performed to establish system accuracy and probe reliability on two numerically controlled machining centers. Commercial software has been revised, and new cycles such as skew check and skew machining, have been developed to enhance and expand probing capabilities. Probe benefits have been demonstrated in the area of setup, cycle time, part quality, tooling cost, and product sampling.

  11. Cold machining of high density tungsten and other materials

    NASA Technical Reports Server (NTRS)

    Ziegelmeier, P.

    1969-01-01

    Cold machining process, which uses a sub-zero refrigerated cutting fluid, is used for machining refractory or reactive metals and alloys. Special carbide tools for turning and drilling these alloys further improve the cutting performance.

  12. Reverse vending machine update

    SciTech Connect

    Rypins, S.; Papke, C.

    1986-02-01

    The document discusses reverse vending machines. Placed outdoors in supermarket parking lots or indoors in the lobby of the grocery market, these hightech machines exchange aluminum cans (or other containers in more specialized machines) for cash, coupons or redeemable receipts. The placement of reverse venders (RV) in or near supermarkets has made recycling more visible and more convenient, although the machines have yet to fully reach industry goals.

  13. Continuous mining machine

    SciTech Connect

    Kiefer, H.E.

    1992-02-11

    This patent describes a continuous mining machine for excavating a longitudinal shaft or tunnel underneath the surface of the earth, the mining machine. It comprises: transport means for moving the machine over a floor of the shaft or tunnel that is being excavated; a working platform having forward and trailing ends.

  14. Apprentice Machine Theory Outline.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Education, Hartford. Div. of Vocational-Technical Schools.

    This volume contains outlines for 16 courses in machine theory that are designed for machine tool apprentices. Addressed in the individual course outlines are the following topics: basic concepts; lathes; milling machines; drills, saws, and shapers; heat treatment and metallurgy; grinders; quality control; hydraulics and pneumatics;…

  15. Children's Understanding of Machines.

    ERIC Educational Resources Information Center

    Brandes, Aaron

    This study, which examined children's understanding of machines, focused on how children decide which objects are machines and which are not, and how they group machines as similar or different. Brainstorming sessions involving two groups of four kindergarten children and one class each from the second, fourth, and fifth grade, were conducted.…

  16. Effects of airborne-particle abrasion, sodium hydroxide anodization, and electrical discharge machining on porcelain adherence to cast commercially pure titanium.

    PubMed

    Acar, Asli; Inan, Ozgür; Halkaci, Selçuk

    2007-07-01

    The aim of this study was to determine the effect of airborne-particle abrasion (APA), sodium hydroxide anodization (SHA), and electrical discharge machining (EDM) on cast titanium surfaces and titanium-porcelain adhesion. Ninety titanium specimens were cast with pure titanium and the alpha-case layer was removed. Specimens were randomly divided into three groups. Ten specimens from each group were subjected to APA. SHA was applied to the second subgroups, and the remaining specimens were subjected to the EDM. For the control group, 10 specimens were cast using NiCr alloy and subjected to only APA. Surfaces were examined by using scanning electron microscope and a surface profilometer. Three titanium porcelains were fused on the titanium surfaces, whereas NiCr specimens were covered with conventional porcelain. Titanium-porcelain adhesion was characterized by a 3-point bending test. Statistical analysis showed that the porcelain-metal bond strength of the control group was higher than that of the titanium-porcelain system (p < 0.05). There were no significant differences between the bond strengths of titanium groups (p 0.05), except the bond strengths of Noritake Super Porcelain TI-22 groups on which APA and SHA were applied (p < 0.05). SHA and EDM as surface treatment did not improve titanium-porcelain adhesion when compared to APA. PMID:17183560

  17. Machine learning methods in chemoinformatics

    PubMed Central

    Mitchell, John B O

    2014-01-01

    Machine learning algorithms are generally developed in computer science or adjacent disciplines and find their way into chemical modeling by a process of diffusion. Though particular machine learning methods are popular in chemoinformatics and quantitative structure–activity relationships (QSAR), many others exist in the technical literature. This discussion is methods-based and focused on some algorithms that chemoinformatics researchers frequently use. It makes no claim to be exhaustive. We concentrate on methods for supervised learning, predicting the unknown property values of a test set of instances, usually molecules, based on the known values for a training set. Particularly relevant approaches include Artificial Neural Networks, Random Forest, Support Vector Machine, k-Nearest Neighbors and naïve Bayes classifiers. WIREs Comput Mol Sci 2014, 4:468–481. How to cite this article: WIREs Comput Mol Sci 2014, 4:468–481. doi:10.1002/wcms.1183 PMID:25285160

  18. Associations of parameters characterizing the time course of the tabletting process on a reciprocating and on a rotary tabletting machine for high-speed production.

    PubMed

    Konkel, P; Mielck, J B

    1998-03-01

    A series of modern direct-compression excipients with differing mechanisms of deformation and densification, Karion Instant Pharma, Vivacel 200, Cellactose, Tablettose, and Parmcompress, after admixing magnesium stearate, have been tabletted (400 mg, 10 mm flat-faced punches) on an eccentric machine, Fette E XI at 43.6 rpm, and on a rotary machine, Fette PT 2090 at 20, 60, and 90 rpm, to graded maximum forces (3, 5, 10, 15 kN, respectively). Force/time (E XI and PT 2090) and displacement/time (E XI) curves were recorded. From the data on the E XI, parameters of a modified Weibull function, slopes of the Heckel function, quotients of partial areas under the curves, and the differences between times of maximum forces and the respective maximum densifications, t(diff), were calculated. From the data on the PT 2090, partial areas under the curves for the upper punch, various quotients of these areas, and the peak-offset times, t(off), the times of maximum force relative to the middle of the dwell time, t(dwell), were calculated. Close associations were found between the area A1 reI during the precompression phase (PT 2090) and the Heckel slope (E XI), between the quotient of partial areas before and after the middle of t(dwell) (PT 2090) and that of partial areas before and after maximum densification (E XI), and between t(off) (PT 2090) and t(diff) (E XI). However, certain materials (e.g. Karion Instant, Vivacel) showed marked deviations in behavior by particular parameters on the two machines. The results from both machines with respect to densification behavior complement one another. PMID:9704910

  19. Experimental investigation on material migration phenomena in micro-EDM of reaction-bonded silicon carbide

    NASA Astrophysics Data System (ADS)

    Liew, Pay Jun; Yan, Jiwang; Kuriyagawa, Tsunemoto

    2013-07-01

    Material migration between tool electrode and workpiece material in micro electrical discharge machining of reaction-bonded silicon carbide was experimentally investigated. The microstructural changes of workpiece and tungsten tool electrode were examined using scanning electron microscopy, cross sectional transmission electron microscopy and energy dispersive X-ray under various voltage, capacitance and carbon nanofibre concentration in the dielectric fluid. Results show that tungsten is deposited intensively inside the discharge-induced craters on the RB-SiC surface as amorphous structure forming micro particles, and on flat surface region as a thin interdiffusion layer of poly-crystalline structure. Deposition of carbon element on tool electrode was detected, indicating possible material migration to the tool electrode from workpiece material, carbon nanofibres and dielectric oil. Material deposition rate was found to be strongly affected by workpiece surface roughness, voltage and capacitance of the electrical discharge circuit. Carbon nanofibre addition in the dielectric at a suitable concentration significantly reduced the material deposition rate.

  20. Waterless Clothes-Cleaning Machine

    NASA Technical Reports Server (NTRS)

    Johnson, Glenn; Ganske, Shane

    2013-01-01

    A waterless clothes-cleaning machine has been developed that removes loose particulates and deodorizes dirty laundry with regenerative chemical processes to make the clothes more comfortable to wear and have a fresher smell. This system was initially developed for use in zero-g, but could be altered for 1-g environments where water or other re sources are scarce. Some of these processes include, but are not limited to, airflow, filtration, ozone generation, heat, ultraviolet light, and photocatalytic titanium oxide.

  1. Perspex machine: VII. The universal perspex machine

    NASA Astrophysics Data System (ADS)

    Anderson, James A. D. W.

    2006-01-01

    The perspex machine arose from the unification of projective geometry with the Turing machine. It uses a total arithmetic, called transreal arithmetic, that contains real arithmetic and allows division by zero. Transreal arithmetic is redefined here. The new arithmetic has both a positive and a negative infinity which lie at the extremes of the number line, and a number nullity that lies off the number line. We prove that nullity, 0/0, is a number. Hence a number may have one of four signs: negative, zero, positive, or nullity. It is, therefore, impossible to encode the sign of a number in one bit, as floating-point arithmetic attempts to do, resulting in the difficulty of having both positive and negative zeros and NaNs. Transrational arithmetic is consistent with Cantor arithmetic. In an extension to real arithmetic, the product of zero, an infinity, or nullity with its reciprocal is nullity, not unity. This avoids the usual contradictions that follow from allowing division by zero. Transreal arithmetic has a fixed algebraic structure and does not admit options as IEEE, floating-point arithmetic does. Most significantly, nullity has a simple semantics that is related to zero. Zero means "no value" and nullity means "no information." We argue that nullity is as useful to a manufactured computer as zero is to a human computer. The perspex machine is intended to offer one solution to the mind-body problem by showing how the computable aspects of mind and, perhaps, the whole of mind relates to the geometrical aspects of body and, perhaps, the whole of body. We review some of Turing's writings and show that he held the view that his machine has spatial properties. In particular, that it has the property of being a 7D lattice of compact spaces. Thus, we read Turing as believing that his machine relates computation to geometrical bodies. We simplify the perspex machine by substituting an augmented Euclidean geometry for projective geometry. This leads to a general-linear perspex-machine which is very much easier to program than the original perspex-machine. We then show how to map the whole of perspex space into a unit cube. This allows us to construct a fractal of perspex machines with the cardinality of a real-numbered line or space. This fractal is the universal perspex machine. It can solve, in unit time, the halting problem for itself and for all perspex machines instantiated in real-numbered space, including all Turing machines. We cite an experiment that has been proposed to test the physical reality of the perspex machine's model of time, but we make no claim that the physical universe works this way or that it has the cardinality of the perspex machine. We leave it that the perspex machine provides an upper bound on the computational properties of physical things, including manufactured computers and biological organisms, that have a cardinality no greater than the real-number line.

  2. Prospective candidates for the EDM experiments of new type: calculations of enhancement of P,T-odd effects in HI+ and liquid Xe

    SciTech Connect

    Isaev, Timur A.; Petrov, Aleksander N.; Mosyagin, Nikolay S.; Titov, Anatoly V.

    2006-07-11

    The search for the P,T-parity non-conservation (PNC) effects is of fundamental importance in physics. Experiments are performed on T1F and YbF, and are prepared on PbO and HgH molecules. Recently some new approaches were suggested, such as the search for P,T-odd effects in liquid xenon and on HI+ molecular ion. For preparation and interpretation of these experiments high-precision calculations of the electronic structure are required. Recently developed theoretical methods allow one to analyze the atomic-molecular systems from the point of enhancement of P,T-odd effects and recommend such or another system as a prospective candidate. We calculated enhancement factor for electron EDM in the ground state of HI+ molecular ion, required for experiment of new type on electron EDM search. The results of calculations of P,T-odd effects in liquid xenon are also discussed.

  3. Improving Energy Efficiency in CNC Machining

    NASA Astrophysics Data System (ADS)

    Pavanaskar, Sushrut S.

    We present our work on analyzing and improving the energy efficiency of multi-axis CNC milling process. Due to the differences in energy consumption behavior, we treat 3- and 5-axis CNC machines separately in our work. For 3-axis CNC machines, we first propose an energy model that estimates the energy requirement for machining a component on a specified 3-axis CNC milling machine. Our model makes machine-specific predictions of energy requirements while also considering the geometric aspects of the machining toolpath. Our model - and the associated software tool - facilitate direct comparison of various alternative toolpath strategies based on their energy-consumption performance. Further, we identify key factors in toolpath planning that affect energy consumption in CNC machining. We then use this knowledge to propose and demonstrate a novel toolpath planning strategy that may be used to generate new toolpaths that are inherently energy-efficient, inspired by research on digital micrography -- a form of computational art. For 5-axis CNC machines, the process planning problem consists of several sub-problems that researchers have traditionally solved separately to obtain an approximate solution. After illustrating the need to solve all sub-problems simultaneously for a truly optimal solution, we propose a unified formulation based on configuration space theory. We apply our formulation to solve a problem variant that retains key characteristics of the full problem but has lower dimensionality, allowing visualization in 2D. Given the complexity of the full 5-axis toolpath planning problem, our unified formulation represents an important step towards obtaining a truly optimal solution. With this work on the two types of CNC machines, we demonstrate that without changing the current infrastructure or business practices, machine-specific, geometry-based, customized toolpath planning can save energy in CNC machining.

  4. Analytical design of intelligent machines

    NASA Technical Reports Server (NTRS)

    Saridis, George N.; Valavanis, Kimon P.

    1987-01-01

    The problem of designing 'intelligent machines' to operate in uncertain environments with minimum supervision or interaction with a human operator is examined. The structure of an 'intelligent machine' is defined to be the structure of a Hierarchically Intelligent Control System, composed of three levels hierarchically ordered according to the principle of 'increasing precision with decreasing intelligence', namely: the organizational level, performing general information processing tasks in association with a long-term memory; the coordination level, dealing with specific information processing tasks with a short-term memory; and the control level, which performs the execution of various tasks through hardware using feedback control methods. The behavior of such a machine may be managed by controls with special considerations and its 'intelligence' is directly related to the derivation of a compatible measure that associates the intelligence of the higher levels with the concept of entropy, which is a sufficient analytic measure that unifies the treatment of all the levels of an 'intelligent machine' as the mathematical problem of finding the right sequence of internal decisions and controls for a system structured in the order of intelligence and inverse order of precision such that it minimizes its total entropy. A case study on the automatic maintenance of a nuclear plant illustrates the proposed approach.

  5. Slip-rate increase at Parkfield in 1993 detected by high-precision EDM and borehole tensor strainmeters

    USGS Publications Warehouse

    Langbein, J.; Gwyther, R.L.; Hart, R.H.G.; Gladwin, M.T.

    1999-01-01

    On two of the instrument networks at Parkfield, California, the two-color Electronic Distance Meter (EDM) network and Borehole Tensor Strainmeter (BTSM) network, we have detected a rate change starting in 1993 that has persisted at least 5 years. These and other instruments capable of measuring crustal deformation were installed at Parkfield in anticipation of a moderate, M6, earthquake on the San Andreas fault. Many of these instruments have been in operation since the mid 1980s and have established an excellent baseline to judge changes in rate of deformation and the coherence of such changes between instruments. The onset of the observed rate change corresponds in time to two other changes at Parkfield. From late 1992 through late 1994, the Parkfield region had an increase in number of M4 to M5 earthquakes relative to the preceding 6 years. The deformation-rate change also coincides with the end of a 7-year period of sub-normal rainfall. Both the spatial coherence of the rate change and hydrological modeling suggest a tectonic explanation for the rate change. From these observations, we infer that the rate of slip increased over the period 1993-1998.On two of the instrument networks at Parkfield, California, the two-color Electronic Distance Meter (EDM) network and Borehole Tensor Strainmeter (BTSM) network, we have detected a rate change starting in 1993 that has persisted at least 5 years. These and other instruments capable of measuring crustal deformation were installed at Parkfield in anticipation of a moderate, M6, earthquake on the San Andreas fault. Many of these instruments have been in operation since the mid 1980s and have established an excellent baseline to judge changes in rate of deformation and the coherence of such changes between instruments. The onset of the observed rate change corresponds in time to two other changes at Parkfield. From late 1992 through late 1994, the Parkfield region had an increase in number of M4 to M5 earthquakes relative to the preceding 6 years. The deformation-rate change also coincides with the end of a 7-year period of sub-normal rainfall. Both the spatial coherence of the rate change and hydrological modeling suggest a tectonic explanation for the rate change. From these observations, we infer that the rate of slip increased over the period 1993-1998.

  6. Strain gradient plasticity theory applied to machining

    SciTech Connect

    Royer, Raphael; Laheurte, Raynald; Darnis, Philippe; Gerard, Alain; Cahuc, Olivier

    2011-05-04

    Machining is the most common manufacturing process. A good behaviour law is necessary in the simulation of machining processes (analytical and finite element modeling). Usually, commonly used behaviour laws such as Jonhson-Cook can bring unsatisfactory results especially for high strain and large deformation processes. Significant differences can appear between experimental and simulation results. The aim of this paper is to present the choices made regarding the behaviour law in this context. This study develops a large deformation strain-gradient theoretical framework with hypothesis linked to metal cutting processes. The theoretical framework has the potential of expressing moments at the tool tip as they were observed in experiments. It will be shown that the theory has the capability of interpreting the complex phenomena found in machining and more particularly in high speed machining.

  7. Machine tool locator

    DOEpatents

    Hanlon, John A.; Gill, Timothy J.

    2001-01-01

    Machine tools can be accurately measured and positioned on manufacturing machines within very small tolerances by use of an autocollimator on a 3-axis mount on a manufacturing machine and positioned so as to focus on a reference tooling ball or a machine tool, a digital camera connected to the viewing end of the autocollimator, and a marker and measure generator for receiving digital images from the camera, then displaying or measuring distances between the projection reticle and the reference reticle on the monitoring screen, and relating the distances to the actual position of the autocollimator relative to the reference tooling ball. The images and measurements are used to set the position of the machine tool and to measure the size and shape of the machine tool tip, and examine cutting edge wear. patent

  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. Laser-assisted machining of difficult-to-machine materials

    SciTech Connect

    Incropera, F.P.; Rozzi, J.C.; Pfefferkorn, F.E.; Lei, S.; Shin, Y.C.

    1999-07-01

    Laser-assisted machining (LAM) is a hybrid process for which a difficult-to-machine material, such as a ceramic or super alloy, is irradiated by a laser source prior to material removal by a cutting tool. The process has the potential to significantly increase material removal rates, as well as to improve the geometry and properties of the finished work piece. Features and limitations of theoretical and experimental procedures for determining the transient thermal response of a work piece during LAM are described, and representative results are presented for laser-assisted turning of sintered silicon nitride. Significant physical trends are revealed by the calculations, as are guidelines for the selection of appropriate operating conditions.

  10. Perspex machine II: visualization

    NASA Astrophysics Data System (ADS)

    Anderson, James A. D. W.

    2005-01-01

    We review the perspex machine and improve it by reducing its halting conditions to one condition. We also introduce a data structure, called the "access column," that can accelerate a wide class of perspex programs. We show how the perspex can be visualised as a tetrahedron, artificial neuron, computer program, and as a geometrical transformation. We discuss the temporal properties of the perspex machine, dissolve the famous time travel paradox, and present a hypothetical time machine. Finally, we discuss some mental properties and show how the perspex machine solves the mind-body problem and, specifically, how it provides one physical explanation for the occurrence of paradigm shifts.

  11. Chaotic Boltzmann machines

    PubMed Central

    Suzuki, Hideyuki; Imura, Jun-ichi; Horio, Yoshihiko; Aihara, Kazuyuki

    2013-01-01

    The chaotic Boltzmann machine proposed in this paper is a chaotic pseudo-billiard system that works as a Boltzmann machine. Chaotic Boltzmann machines are shown numerically to have computing abilities comparable to conventional (stochastic) Boltzmann machines. Since no randomness is required, efficient hardware implementation is expected. Moreover, the ferromagnetic phase transition of the Ising model is shown to be characterised by the largest Lyapunov exponent of the proposed system. In general, a method to relate probabilistic models to nonlinear dynamics by derandomising Gibbs sampling is presented. PMID:23558425

  12. Debugging the virtual machine

    SciTech Connect

    Miller, P.; Pizzi, R.

    1994-09-02

    A computer program is really nothing more than a virtual machine built to perform a task. The program`s source code expresses abstract constructs using low level language features. When a virtual machine breaks, it can be very difficult to debug because typical debuggers provide only low level machine implementation in formation to the software engineer. We believe that the debugging task can be simplified by introducing aspects of the abstract design into the source code. We introduce OODIE, an object-oriented language extension that allows programmers to specify a virtual debugging environment which includes the design and abstract data types of the virtual machine.

  13. Perspex machine II: visualization

    NASA Astrophysics Data System (ADS)

    Anderson, James A. D. W.

    2004-12-01

    We review the perspex machine and improve it by reducing its halting conditions to one condition. We also introduce a data structure, called the "access column," that can accelerate a wide class of perspex programs. We show how the perspex can be visualised as a tetrahedron, artificial neuron, computer program, and as a geometrical transformation. We discuss the temporal properties of the perspex machine, dissolve the famous time travel paradox, and present a hypothetical time machine. Finally, we discuss some mental properties and show how the perspex machine solves the mind-body problem and, specifically, how it provides one physical explanation for the occurrence of paradigm shifts.

  14. 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.

  15. Unified universal quantum cloning machine and fidelities

    SciTech Connect

    Wang Yinan; Shi Handuo; Xiong Zhaoxi; Jing Li; Mu Liangzhu; Ren Xijun; Fan Heng

    2011-09-15

    We present a unified universal quantum cloning machine, which combines several different existing universal cloning machines together, including the asymmetric case. In this unified framework, the identical pure states are projected equally into each copy initially constituted by input and one half of the maximally entangled states. We show explicitly that the output states of those universal cloning machines are the same. One importance of this unified cloning machine is that the cloning procession is always the symmetric projection, which reduces dramatically the difficulties for implementation. Also, it is found that this unified cloning machine can be directly modified to the general asymmetric case. Besides the global fidelity and the single-copy fidelity, we also present all possible arbitrary-copy fidelities.

  16. Effect of electric discharge machining on the fatigue life of Inconel 718

    NASA Technical Reports Server (NTRS)

    Jeelani, S.; Collins, M. R.

    1988-01-01

    The effect of electric discharge machining on the fatigue life of Inconel 718 alloy at room temperature was investigated. Data were generated in the uniaxial tension fatigue mode at ambient temperature using flat 3.175 mm thick specimens. The specimens were machined on a wire-cut electric discharge machine at cutting speeds ranging from 0.5 to 2 mm per minute. The specimens were fatigued at a selected stress, and the resulting fatigue lives compared with that of the virgin material. The surfaces of the fatigued specimens were examined under optical and scanning electron microscopes, and the roughness of the surfaces was measured using a standard profilometer. From the results of the investigation, it was concluded that the fatigue life of the specimens machined using EDM decreased slightly as compared with that of the virgin material, but remained unchanged as the cutting speed was changed. The results are explained using data produced employing microhardness measurements, profilometry, and optical and scanning microscopy.

  17. The Higgs Machine Learning Challenge

    NASA Astrophysics Data System (ADS)

    Adam-Bourdarios, C.; Cowan, G.; Germain-Renaud, C.; Guyon, I.; Kégl, B.; Rousseau, D.

    2015-12-01

    The Higgs Machine Learning Challenge was an open data analysis competition that took place between May and September 2014. Samples of simulated data from the ATLAS Experiment at the LHC corresponding to signal events with Higgs bosons decaying to τ+τ- together with background events were made available to the public through the website of the data science organization Kaggle (kaggle.com). Participants attempted to identify the search region in a space of 30 kinematic variables that would maximize the expected discovery significance of the signal process. One of the primary goals of the Challenge was to promote communication of new ideas between the Machine Learning (ML) and HEP communities. In this regard it was a resounding success, with almost 2,000 participants from HEP, ML and other areas. The process of understanding and integrating the new ideas, particularly from ML into HEP, is currently underway.

  18. Meso-scale machining capabilities and issues

    SciTech Connect

    BENAVIDES,GILBERT L.; ADAMS,DAVID P.; YANG,PIN

    2000-05-15

    Meso-scale manufacturing processes are bridging the gap between silicon-based MEMS processes and conventional miniature machining. These processes can fabricate two and three-dimensional parts having micron size features in traditional materials such as stainless steels, rare earth magnets, ceramics, and glass. Meso-scale processes that are currently available include, focused ion beam sputtering, micro-milling, micro-turning, excimer laser ablation, femto-second laser ablation, and micro electro discharge machining. These meso-scale processes employ subtractive machining technologies (i.e., material removal), unlike LIGA, which is an additive meso-scale process. Meso-scale processes have different material capabilities and machining performance specifications. Machining performance specifications of interest include minimum feature size, feature tolerance, feature location accuracy, surface finish, and material removal rate. Sandia National Laboratories is developing meso-scale electro-mechanical components, which require meso-scale parts that move relative to one another. The meso-scale parts fabricated by subtractive meso-scale manufacturing processes have unique tribology issues because of the variety of materials and the surface conditions produced by the different meso-scale manufacturing processes.

  19. Integral Plug-Type Heat-Flux Gauge

    NASA Technical Reports Server (NTRS)

    Liebert, Curt H.; Koch, John, Jr.

    1991-01-01

    Integral thermoplug gauge measures flux of heat across specimen of material. New gauge not screwed or welded into place, but instead thermoplug and annulus electrical-discharge-machined (EDM) into specimen material. EDM process leaves no interface between material and thermoplug, thus inherently increasing gauge accuracy by eliminating interface and associated temperature discontinuity. Process also conducive to accurate fabrication of minute gauges.

  20. Simple Machines Made Simple.

    ERIC Educational Resources Information Center

    St. Andre, Ralph E.

    Simple machines have become a lost point of study in elementary schools as teachers continue to have more material to cover. This manual provides hands-on, cooperative learning activities for grades three through eight concerning the six simple machines: wheel and axle, inclined plane, screw, pulley, wedge, and lever. Most activities can be

  1. Stirling machine operating experience

    SciTech Connect

    Ross, B.; Dudenhoefer, J.E.

    1994-09-01

    Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that stirling machines are capable of reliable and lengthy operating lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and are not expected to operate for lengthy periods of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered. The record in this paper is not complete, due to the reluctance of some organizations to release operational data and because several organizations were not contacted. The authors intend to repeat this assessment in three years, hoping for even greater participation.

  2. Simple Machines Made Simple.

    ERIC Educational Resources Information Center

    St. Andre, Ralph E.

    Simple machines have become a lost point of study in elementary schools as teachers continue to have more material to cover. This manual provides hands-on, cooperative learning activities for grades three through eight concerning the six simple machines: wheel and axle, inclined plane, screw, pulley, wedge, and lever. Most activities can be…

  3. Compound taper milling machine

    NASA Technical Reports Server (NTRS)

    Campbell, N. R.

    1969-01-01

    Simple, inexpensive milling machine tapers panels from a common apex to a uniform height at panel edge regardless of the panel perimeter configuration. The machine consists of an adjustable angled beam upon which the milling tool moves back and forth above a rotatable table upon which the workpiece is held.

  4. Simple Machine Junk Cars

    ERIC Educational Resources Information Center

    Herald, Christine

    2010-01-01

    During the month of May, the author's eighth-grade physical science students study the six simple machines through hands-on activities, reading assignments, videos, and notes. At the end of the month, they can easily identify the six types of simple machine: inclined plane, wheel and axle, pulley, screw, wedge, and lever. To conclude this unit,…

  5. Machine Translation Project

    NASA Technical Reports Server (NTRS)

    Bajis, Katie

    1993-01-01

    The characteristics and capabilities of existing machine translation systems were examined and procurement recommendations were developed. Four systems, SYSTRAN, GLOBALINK, PC TRANSLATOR, and STYLUS, were determined to meet the NASA requirements for a machine translation system. Initially, four language pairs were selected for implementation. These are Russian-English, French-English, German-English, and Japanese-English.

  6. Simple Machine Junk Cars

    ERIC Educational Resources Information Center

    Herald, Christine

    2010-01-01

    During the month of May, the author's eighth-grade physical science students study the six simple machines through hands-on activities, reading assignments, videos, and notes. At the end of the month, they can easily identify the six types of simple machine: inclined plane, wheel and axle, pulley, screw, wedge, and lever. To conclude this unit,

  7. Semantics via Machine Translation

    ERIC Educational Resources Information Center

    Culhane, P. T.

    1977-01-01

    Recent experiments in machine translation have given the semantic elements of collocation in Russian more objective criteria. Soviet linguists in search of semantic relationships have attempted to devise a semantic synthesis for construction of a basic language for machine translation. One such effort is summarized. (CHK)

  8. Automatic soldering machine

    NASA Technical Reports Server (NTRS)

    Stein, J. A.

    1974-01-01

    Fully-automatic tube-joint soldering machine can be used to make leakproof joints in aluminum tubes of 3/16 to 2 in. in diameter. Machine consists of temperature-control unit, heater transformer and heater head, vibrator, and associated circuitry controls, and indicators.

  9. Nano Mechanical Machining Using AFM Probe

    NASA Astrophysics Data System (ADS)

    Mostofa, Md. Golam

    Complex miniaturized components with high form accuracy will play key roles in the future development of many products, as they provide portability, disposability, lower material consumption in production, low power consumption during operation, lower sample requirements for testing, and higher heat transfer due to their very high surface-to-volume ratio. Given the high market demand for such micro and nano featured components, different manufacturing methods have been developed for their fabrication. Some of the common technologies in micro/nano fabrication are photolithography, electron beam lithography, X-ray lithography and other semiconductor processing techniques. Although these methods are capable of fabricating micro/nano structures with a resolution of less than a few nanometers, some of the shortcomings associated with these methods, such as high production costs for customized products, limited material choices, necessitate the development of other fabricating techniques. Micro/nano mechanical machining, such an atomic force microscope (AFM) probe based nano fabrication, has, therefore, been used to overcome some the major restrictions of the traditional processes. This technique removes material from the workpiece by engaging micro/nano size cutting tool (i.e. AFM probe) and is applicable on a wider range of materials compared to the photolithographic process. In spite of the unique benefits of nano mechanical machining, there are also some challenges with this technique, since the scale is reduced, such as size effects, burr formations, chip adhesions, fragility of tools and tool wear. Moreover, AFM based machining does not have any rotational movement, which makes fabrication of 3D features more difficult. Thus, vibration-assisted machining is introduced into AFM probe based nano mechanical machining to overcome the limitations associated with the conventional AFM probe based scratching method. Vibration-assisted machining reduced the cutting forces and burr formations through intermittent cutting. Combining the AFM probe based machining with vibration-assisted machining enhanced nano mechanical machining processes by improving the accuracy, productivity and surface finishes. In this study, several scratching tests are performed with a single crystal diamond AFM probe to investigate the cutting characteristics and model the ploughing cutting forces. Calibration of the probe for lateral force measurements, which is essential, is also extended through the force balance method. Furthermore, vibration-assisted machining system is developed and applied to fabricate different materials to overcome some of the limitations of the AFM probe based single point nano mechanical machining. The novelty of this study includes the application of vibration-assisted AFM probe based nano scale machining to fabricate micro/nano scale features, calibration of an AFM by considering different factors, and the investigation of the nano scale material removal process from a different perspective.

  10. Dictionary machine (for VLSI)

    SciTech Connect

    Ottmann, T.A.; Rosenberg, A.L.; Stockmeyer, L.J.

    1982-09-01

    The authors present the design of a dictionary machine that is suitable for VLSI implementation, and discusses how to realize this implementation efficiently. The machine supports the operations of search, insert, delete, and extractment on an arbitrary ordered set. Each of these operations takes time o(logn), where n is the number of entries present when the operation is performed. Moreover, arbitrary sequences of these instructions can be pipelined through the machine at a constant rate (i.e. independent of n and the capacity of the machine). The time o(logn) is an improvement over previous VLSI designs of dictionary machines which require time o(log n) per operation, where n is the maximum number of keys that can be stored. 10 references.

  11. Machinability of a Stainless Steel by Electrochemical Discharge Microdrilling

    SciTech Connect

    Coteata, Margareta; Pop, Nicolae; Slatineanu, Laurentiu; Schulze, Hans-Peter; Besliu, Irina

    2011-05-04

    Due to the chemical elements included in their structure for ensuring an increased resistance to the environment action, the stainless steels are characterized by a low machinability when classical machining methods are applied. For this reason, sometimes non-traditional machining methods are applied, one of these being the electrochemical discharge machining. To obtain microholes and to evaluate the machinability by electrochemical discharge microdrilling, test pieces of stainless steel were used for experimental research. The electrolyte was an aqueous solution of sodium silicate with different densities. A complete factorial plan was designed to highlight the influence of some input variables on the sizes of the considered machinability indexes (electrode tool wear, material removal rate, depth of the machined hole). By mathematically processing of experimental data, empirical functions were established both for stainless steel and carbon steel. Graphical representations were used to obtain more suggestive vision concerning the influence exerted by the considered input variables on the size of the machinability indexes.

  12. BRITISH MOLDING MACHINE, PBQ AUTOMATIC COPE AND DRAG MOLDING MACHINE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BRITISH MOLDING MACHINE, PBQ AUTOMATIC COPE AND DRAG MOLDING MACHINE MAKES BOTH MOLD HALVES INDIVIDUALLY WHICH ARE LATER ROTATED, ASSEMBLED, AND LOWERED TO POURING CONVEYORS BY ASSISTING MACHINES. - Southern Ductile Casting Company, Casting, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  13. 14. Interior, Machine Shop, Roundhouse Machine Shop Extension, Southern Pacific ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Interior, Machine Shop, Roundhouse Machine Shop Extension, Southern Pacific Railroad Carlin Shops, view to north (90mm lens). - Southern Pacific Railroad, Carlin Shops, Roundhouse Machine Shop Extension, Foot of Sixth Street, Carlin, Elko County, NV

  14. Machine Learning for Biomedical Literature Triage

    PubMed Central

    Almeida, Hayda; Meurs, Marie-Jean; Kosseim, Leila; Butler, Greg; Tsang, Adrian

    2014-01-01

    This paper presents a machine learning system for supporting the first task of the biological literature manual curation process, called triage. We compare the performance of various classification models, by experimenting with dataset sampling factors and a set of features, as well as three different machine learning algorithms (Naive Bayes, Support Vector Machine and Logistic Model Trees). The results show that the most fitting model to handle the imbalanced datasets of the triage classification task is obtained by using domain relevant features, an under-sampling technique, and the Logistic Model Trees algorithm. PMID:25551575

  15. Machine vision for real time orbital operations

    NASA Technical Reports Server (NTRS)

    Vinz, Frank L.

    1988-01-01

    Machine vision for automation and robotic operation of Space Station era systems has the potential for increasing the efficiency of orbital servicing, repair, assembly and docking tasks. A machine vision research project is described in which a TV camera is used for inputing visual data to a computer so that image processing may be achieved for real time control of these orbital operations. A technique has resulted from this research which reduces computer memory requirements and greatly increases typical computational speed such that it has the potential for development into a real time orbital machine vision system. This technique is called AI BOSS (Analysis of Images by Box Scan and Syntax).

  16. Integrated reverse engineering and machining system

    NASA Astrophysics Data System (ADS)

    Li, Jianjun; Chow, Joe; Chen, Chinsheng; Xu, TianDi; Tsai, David; Xue, Weidong

    1998-10-01

    This paper deals with the integration of reverse engineering with CAM for duplicating an existing part without a CAD model quickly and accurately. Two commercial packages, SURFACER and SmartCAM, were selected as the software tools for reverse engineering and NC code generation respectively. By utilizing the open architecture environment provided by SURFACER, a machining-oriented feature model can be constructed during the model creation phase. This model consists of not only the part's geometric entities but also all the machining information required for toolpath generation. Upon a knowledge-based process planning, this machining-oriented feature model is converted into a process model, which will then be used to create a job file and a macro file, both in the SmartCAM format. The execution of these two files inside SmartCAM can automatically generate the toolpaths and NC codes required for part machining.

  17. Sensor fusion method for machine performance enhancement

    SciTech Connect

    Mou, J.I.; King, C.; Hillaire, R.; Jones, S.; Furness, R.

    1998-03-01

    A sensor fusion methodology was developed to uniquely integrate pre-process, process-intermittent, and post-process measurement and analysis technology to cost-effectively enhance the accuracy and capability of computer-controlled manufacturing equipment. Empirical models and computational algorithms were also developed to model, assess, and then enhance the machine performance.

  18. Implementing nested conditional statements in SIMD machines

    NASA Technical Reports Server (NTRS)

    Middleton, David

    1989-01-01

    Single instruction, multiple data (SIMD) computers consist of a very large number of processors executing a common sequence of instructions. Maintaining the full speedup potential of such machines is most sensitive to conditional execution in their programs, regions of code where some processing elements (PEs) perform no useful work. Techniques are presented for efficiently implementing nested conditional statements, specifically if and case statements, in SIMD machines, while adding minimal specialized hardware.

  19. The pendulum wave machine

    NASA Astrophysics Data System (ADS)

    Zetie, K. P.

    2015-05-01

    There are many examples on the internet of videos of pendulum wave machines and how to make them (for example, www.instructables.com/id/Wave-Pendulum/). The machine is simply a set of pendula of different lengths which, when viewed end on, produce wave-like patterns from the positions of the bobs. These patterns change with time, with new patterns emerging as the bobs change phase. In this article, the physics of the machine is explored and explained, along with tips on how to build such a device.

  20. Quantum Boltzmann Machine

    NASA Astrophysics Data System (ADS)

    Kulchytskyy, Bohdan; Andriyash, Evgeny; Amin, Mohammed; Melko, Roger

    The field of machine learning has been revolutionized by the recent improvements in the training of deep networks. Their architecture is based on a set of stacked layers of simpler modules. One of the most successful building blocks, known as a restricted Boltzmann machine, is an energetic model based on the classical Ising Hamiltonian. In our work, we investigate the benefits of quantum effects on the learning capacity of Boltzmann machines by extending its underlying Hamiltonian with a transverse field. For this purpose, we employ exact and stochastic training procedures on data sets with physical origins.