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1

AFM surface imaging of AISI D2 tool steel machined by the EDM process  

Microsoft Academic Search

The surface morphology, surface roughness and micro-crack of AISI D2 tool steel machined by the electrical discharge machining (EDM) process were analyzed by means of the atomic force microscopy (AFM) technique. Experimental results indicate that the surface texture after EDM is determined by the discharge energy during processing. An excellent machined finish can be obtained by setting the machine parameters

Y. H. Guu

2005-01-01

2

Machining characteristics of titanium alloy (Ti–6Al–4V) using a combination process of EDM with USM  

Microsoft Academic Search

This paper presents an experimental investigation of the machining characteristics of titanium alloy (Ti–6Al–4V) using a combination process of electro-discharge machining (EDM) with ultrasonic machining (USM). The EDM and USM machining mechanisms were integrated to improve the machining efficiency and accuracy. During the experiments, parameters such as dielectric type, abrasive size, concentration of abrasive in the dielectric fluid, discharge peak

Yan Cherng Lin; Biing Hwa Yan; Yong Song Chang

2000-01-01

3

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

PubMed

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

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

2010-01-01

4

QU, JUN. Development of Cylindrical Wire Electrical Discharge Machining Process and Investigation of Surface Integrity and Mechanical Property of EDM Surface  

E-print Network

and recast layer and to understand the effects of wire EDM process on the machined WC-Co surface. The micro-sections. The undesired recast layer, which has poor mechanical properties and irregular features, was eventually removed and Investigation of Surface Integrity and Mechanical Property of EDM Surface Layers. (Under the direction of Albert

Shih, Albert J.

5

New technologies and applications of EDM process  

Microsoft Academic Search

Within the Faculty of Machine Building from the Technical University of Cluj-Napoca, Romania unconventional technologies researches\\u000a were performed for 20 years. The team focused on national research projects referring to micro machining and special applications.\\u000a EDM process (Electric Discharge Machining) has a great importance to the industry. Even if it never be able to compete with\\u000a the metal cutting manufacturing

Marcel Sabin Popa; Glad Contiu; Grigore Pop; Preja Dan

2009-01-01

6

Selection of EDM Process Parameters Using Biogeography-Based Optimization Algorithm  

Microsoft Academic Search

Amongst the nontraditional machining processes, electric discharge machining (EDM) is considered to be one of the most important processes for machining intricate and complex shapes in various electrically conductive materials, including high-strength, temperature-resistant (HSTR) alloys, especially in aeronautical and automotive industries. For achieving the best performance of the EDM process, it is imperative to carry out parametric design which involves

Rajarshi Mukherjee; Shankar Chakraborty

2012-01-01

7

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

NASA Astrophysics Data System (ADS)

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.

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

2012-09-01

8

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

NASA Technical Reports Server (NTRS)

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.

Rhew, Ray D.

1989-01-01

9

Study of the surface integrity of the machined workpiece in the EDM of tungsten carbide  

Microsoft Academic Search

A comprehensive study of the surface integrity of the machined workpiece in the electrical discharge machining (EDM) of tungsten carbide is presented in this paper. EDM tests on a tungsten carbide workpiece were conducted on a Charmilles Technologies Roboform 40 EDM Die-Sinking Machine, with the peak current and pulse duration varied. The EDMed surface morphology was examined with a scanning

Soo Hiong Lee; Xiaoping Li

2003-01-01

10

Electrical Discharge Machining (EDM) Characteristics Associated with Electrical Discharge Energy on Machining of Cemented Tungsten Carbide  

Microsoft Academic Search

In this investigation, cemented tungsten carbides graded K10 and P10 were machined by electrical discharge machining (EDM) using an electrolytic copper electrode. The machining parameters of EDM were varied to explore the effects of electrical discharge energy on the machining characteristics, such as material removal rate (MRR), electrode wear rate (EWR), and surface roughness. Moreover, the effects of the electrical

Yan-Cherng Lin; Yuan-Feng Chen; Ching-Tien Lin; Hsinn-Jyh Tzeng

2008-01-01

11

Effect of Titanium Carbide particle addition in the aluminium composite on EDM process parameters  

Microsoft Academic Search

Machining of hard materials such as metal matrix composites (Al\\/TiC) to a high degree of accuracy and surface finish is difficult. Electrical discharge machining (EDM) is an important process for machining difficult-to-machine materials like metal matrix composites. EDM is an effective tool in shaping such difficult-to-machine materials. The objective of this work is to investigate the effect of current (C),

Velusamy Senthilkumar; Bidwai Uday Omprakash

2011-01-01

12

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

NASA Astrophysics Data System (ADS)

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.

Sreebalaji, V. S.; Saravanan, R.

13

Selection of EDM Process Parameters Using Biogeography-Based Optimization Algorithm  

Microsoft Academic Search

Amongst the non-traditional machining processes, electric discharge machining (EDM) is considered to be one of the most important processes for machining intricate and complex shapes in various electrically conductive materials, including high-strength, temperature-resistant (HSTR) alloys, especially in aeronautical and automotive industries. For achieving the best performance of the EDM process, it is imperative to carry out parametric design which involves

Rajarshi Mukherjee; Shankar Chakraborty

2011-01-01

14

Surface Integrity of C-40 Steel Processed with WC-Cu Powder Metallurgy Green Compact Tools in EDM  

Microsoft Academic Search

Electric discharge machining (EDM) is an electrothermal process where recast layer on the machined surface and heat-affected (HAZ) zone just below the machined surface are common phenomena. Thus, the assessment of surface integrity in EDM is a very important task. In this study, an attempt was made to modify the surface integrity of C-40 steel in EDM. WC-Cu powder metallurgy

P. K. Patowari; U. K. Mishra; P. Saha; P. K. Mishra

2011-01-01

15

Investigation on the influence of machining parameters when machining tool steel using EDM  

Microsoft Academic Search

Copper electrodes with diameter of 9.5, 12 and 20mm were used in electrodischarge machining (EDM) of AISI 1045 tool steel at two current setting of 3.5 and 6.5A with the objective of determining possible correlation between the EDM parameter (current) and the machinability factors (material removal rate and electrode wear rate). Each machining test was performed for 20min and kerosene

C. H. Che Haron; A. Ginting; M. Fauziah

2001-01-01

16

MACHINING STABILITY OF WIRE EDM OF TITANIUM.  

E-print Network

??This work presents an experimental investigation of wire electro-discharge machining (WEDM) of titanium alloy. The outstanding characteristics of titanium alloys such as their compatibility and… (more)

Nourbakhsh, Farnaz

2012-01-01

17

Grey Relational Analysis of Micro EDM Machining of Ti6Al4V Alloy  

Microsoft Academic Search

In the present work, micro electric discharge machining (micro EDM) of Ti-6Al-V alloy with tungsten carbide electrode has been performed. Ti-6Al-4 V, which is difficult to machine via conventional machining techniques, however, can be easily machined via EDM machining, with careful selection of machining parameters for getting optimum results. In this study, the effect of various input parameters; current, voltage, frequency

Vijay Kumar Meena; Man Singh Azad

2011-01-01

18

Grey Relational Analysis of Micro-EDM Machining of Ti6Al4V Alloy  

Microsoft Academic Search

In the present work, micro-electric discharge machining (micro-EDM) of Ti-6Al-V alloy with tungsten carbide electrode has been performed. Ti-6Al-4V, which is difficult to machine via conventional machining techniques, however, can be easily machined via EDM machining, with careful selection of machining parameters for getting optimum results. In this study, the effect of various input parameters; current, voltage, frequency, and width,

Vijay Kumar Meena; Man Singh Azad

2012-01-01

19

3D surface characterisation of electropolished EDMed surface and quantitative assessment of process variables using Taguchi Methodology  

Microsoft Academic Search

The electro discharge machining (EDM) process produces surfaces that require some form of finishing operation. This is done in order to improve the surface texture and appearance of the component’s surface. However, it is also desirable to remove the white uppermost recast layer (produced by the EDM process) so as to improve the functional performance of the surface. Electropolishing or

H Ramasawmy; L Blunt

2002-01-01

20

The influence of generator actuation mode and process parameters on the performance of finish EDM of a tool steel  

Microsoft Academic Search

The AISI P20 steel is applied by the tooling industry as material for injection molding. It is known that the EDM process parameters technology installed at the majority of CNC EDM machines do not cover some of the necessities of the tooling industry concerning process parameters for a wide range of workpiece materials. Considering this situation, the customers are required

F. L. Amorim; W. L. Weingaertner

2005-01-01

21

Optimization of EDM process for multiple performance characteristics using Taguchi method and Grey relational analysis  

Microsoft Academic Search

Electrical discharge machining (EDM) is one of the most extensively used non-conventional material removal processes. The\\u000a Taguchi method has been utilized to determine the optimal EDM conditions in several industrial fields. The method, however,\\u000a was designed to optimize only a single performance characteristic. To remove that limitation, the Grey relational analysis\\u000a theory has been used to resolve the complicated interrelationships

Jong Hyuk Jung; Won Tae Kwon

2010-01-01

22

Process characterization of Electrical Discharge Machining of highly doped silicon  

E-print Network

Electrical Discharge Machining (EDM) is an advanced machining process that removes material via thermal erosion through a plasma arc. The machining process is accomplished through the application of high frequency current ...

Crawford, Gregory Allan

2012-01-01

23

Insight into fundamental aspects of the EDM process using multidischarge numerical simulation  

Microsoft Academic Search

The electrical discharge machining (EDM) process is a popular non-traditional machining process, but, although it is widely\\u000a used in industry, there is still a lack of scientific knowledge about its fundamentals. This paper discusses some aspects\\u000a of the discharge process at the sight of the results obtained with a previously developed thermal model, which is capable\\u000a of simulating the superposition

Borja Izquierdo; José Antonio Sánchez; Naiara Ortega; Soraya Plaza; Iñigo Pombo

2011-01-01

24

Comparative study of different dielectrics for micro-EDM performance during microhole machining of Ti6Al4V alloy  

Microsoft Academic Search

In microelectrodischarge machining (micro-EDM), dielectric plays an important role during machining operation. The machining\\u000a characteristics are greatly influenced by the nature of dielectric used during micro-EDM machining. Present paper addresses\\u000a the issues of micro-EDM utilizing different types of dielectrics such as kerosene, deionized water, boron carbide (B4C) powder suspended kerosene, and deionized water to explore the influence of these dielectrics

G. Kibria; B. R. Sarkar; B. B. Pradhan; B. Bhattacharyya

2010-01-01

25

Cylindrical Wire Electrical Discharge Machining Process Development  

Microsoft Academic Search

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

Jun Qu; Albert J. Shih; Ron O. Scattergood; Samuel B. McSpadden

26

An analysis of overcut variation and coupling effects of dimensional variable in EDM process  

Microsoft Academic Search

In the electrical discharge machining (EDM) process, the overcut greatly affects the precision and accuracy of the workpiece\\u000a dimensions. However, the overcut and the final workpiece dimensions are difficult to predict due to the non-linear, complex\\u000a relationship among the electrode wear, the electrode diameter, electrical discharging parameters, and the machine positioning\\u000a accuracy. In the present study, the variation of the

Hao Ning Chiang; J. J. Junz Wang

2011-01-01

27

INVESTIGATING THE EFFECTS OF EDM PARAMETERS ON SURFACE INTEGRITY, MRR AND TWR IN MACHINING OF Ti–6Al–4V  

Microsoft Academic Search

Ti–6Al–4V is a kind of difficult-to-cut material with poor machinability by traditional machining methods, while electrical discharge machining (EDM) is suitable for machining titanium alloys. In this paper, three input machining parameters including pulse current, pulse on time and open circuit voltage were changed during EDM tests. To investigate the output characteristics; material removal rate (MRR), tool wear ratio (TWR)

B. Jabbaripour; M. H. Sadeghi; Sh. Faridvand; M. R. Shabgard

2012-01-01

28

Study on Factors Determining Limits of Minimum Machinable Size in Micro EDM  

Microsoft Academic Search

This paper describes an investigation on factors determining the limits of the minimum machinable diameter of micro rods obtained by micro EDM. Possible factors which influence the limits are discharge crater size, depth of heat affected zone, residual stress, and material micro-structure. In this paper, the influences of residual stress and material micro-structure were especially examined. For the negative effects

T. Kawakami; M. Kunieda

2005-01-01

29

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

NASA Technical Reports Server (NTRS)

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.

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

1967-01-01

30

Development of the Cylindrical Wire Electrical Discharge Machining Process.  

SciTech Connect

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.

McSpadden, SB

2002-01-22

31

Development of the Cylindrical Wire Electrical Discharge Machining Process  

Microsoft Academic Search

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

McSpadden

2002-01-01

32

A new method of optimising material removal rate using EDM with copper–tungsten electrodes  

Microsoft Academic Search

Electrical discharge machining (EDM) is widely used in the production of dies. This paper describes an investigation into the optimisation of the process which uses the effect of carbon which has migrated from the dielectric to tungsten–copper electrodes. This work has led to the development of a two-stage EDM machining process where different EDM settings are used for the two

Jose Marafona; Catherine Wykes

2000-01-01

33

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

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

34

Environmental constituents of Electrical Discharge Machining  

E-print Network

Electrical Discharge Machining (EDM) is a non-traditional process that uses no mechanical forces to machine metals. It is extremely useful in machining hard materials. With the advantages EDM has to offer and its presence ...

Cho, Margaret H. (Margaret Hyunjoo), 1982-

2004-01-01

35

Electrical Discharge Machining.  

ERIC Educational Resources Information Center

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,…

Montgomery, C. M.

36

Monitor For Electrical-Discharge Machining  

NASA Technical Reports Server (NTRS)

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.

Burley, Richard K.

1993-01-01

37

Study of the effect of machining parameters on the machining characteristics in electrical discharge machining of tungsten carbide  

Microsoft Academic Search

Electrical discharge machining (EDM) is a process for shaping hard metals and forming deep and complex-shaped holes by arc erosion in all kinds of electro-conductive materials. The objective of this research is to study the influence of operating parameters of EDM of tungsten carbide on the machining characteristics. The effectiveness of the EDM process with tungsten carbide is evaluated in

S. H. Lee; X. P. Li

2001-01-01

38

Experimental Study on Influence of Process Variables on Crater Dimensions in Micro- EDM of ? -Titanium Aluminide  

NASA Astrophysics Data System (ADS)

In the present work the effect of different dielectric mediums in micro-EDM of ?-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.

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

2011-01-01

39

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

PubMed

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

Ling, Tsz Yan; Pui, David Y H

2013-11-19

40

Investigation of EDM characteristics of nickel-based heat resistant alloy  

Microsoft Academic Search

The EDM processing characteristics of one of the nickel-based heat resistant alloys, Hast-elloy-X, were investigated under\\u000a the various EDM conditions and analyzed in terms of surface integrity. This alloy is commonly used as a material for the hot\\u000a gas path component of gas turbines and it is difficult to machine by conventional machining methods. The primary EDM parameter\\u000a which was

Sin Ho Kang; Dae Eun Kim

2003-01-01

41

Effects of finishing processes on the fatigue life improvements of electro-machined surfaces of tool steel  

Microsoft Academic Search

Machining the EN X160CrMoV12 tool steel by electro-discharge machining (EDM) process generates significant modifications of\\u000a microgeometrical, microstructural and mechanical properties of the upper layers of the machined components. In this paper,\\u000a the role of these modifications in controlling the stability, under cyclic loading, of the propagation of the crack networks\\u000a generated by EDM is discussed. High cycle fatigue tests (2?×?106

Farhat Ghanem; Nabil Ben Fredj; Habib Sidhom; Chedly Braham

2011-01-01

42

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

NASA Astrophysics Data System (ADS)

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.

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

2012-10-01

43

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

SciTech Connect

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.

Newton, Thomas R [Georgia Institute of Technology; Melkote, Shreyes N [Georgia Institute of Technology; Watkins, Thomas R [ORNL; Trejo, Rosa M [ORNL; Riester, Laura [ORNL

2009-01-01

44

Intelligent Modeling and Multiobjective Optimization of Die Sinking Electrochemical Spark Machining Process  

Microsoft Academic Search

Die sinking–electrochemical spark machining (DS–ECSM) is one of the hybrid machining processes, combining the features of electrochemical machining (ECM) and electro-discharge machining (EDM), used for machining of nonconducting materials. This article reports an intelligent approach for the modelling of DS–ECSM process using finite element method (FEM) and artificial neural network (ANN) in integrated manner. It primarily comprises development of two

Mohan Charan Panda; Vinod Yadava

2012-01-01

45

Intelligent Modeling and Multi–Objective Optimization of Die Sinking ElectroChemical Spark Machining Process  

Microsoft Academic Search

Die Sinking–Electro Chemical Spark Machining (DS–ECSM) is one of the hybrid machining processes, combining the features of Electro Chemical Machining (ECM) and Electro Discharge Machining (EDM), used for machining of non-conducting materials. This paper reports, an intelligent approach for the modelling of DS–ECSM process using FEM and ANN in integrated manner. It primarily comprises development of two models. First one

Mohan Charan Panda; Vinod Yadava

2011-01-01

46

Study on an evaluation method of micro CMM spherical stylus tips by µ-EDM on-machine measurement  

NASA Astrophysics Data System (ADS)

This paper describes an on-machine measurement function of a micro electro-discharge machine (µ-EDM) to evaluate the quality of micro ball-ended stylus tips fabricated by a combination of wire-electro-discharge grinding (WEDG) and one-pulse-electro-discharge (OPED) technology. A low-voltage contacting trigger function without any capacitor between a stationary wire and the spindle of a µ-EDM was used to measure the outer profile and evaluate the forming quality. The measurement results show that the deviation of the largest radius between the micro ball-ended tip and stem is approximately 3 µm. Moreover, OPED/WEDG is also easily able to produce high-quality micro spherical stylus tips with a standard deviation as small as 0.7 µm through use of sharp-needle-shaped electrode tools. With further improvements in electro-discharge position, OPED and WEDG technology are promising and excellent approaches for manufacturing micro coordinate measurement machine (CMM) spherical stylus tips.

Sheu, Dong-Yea

2010-07-01

47

Ultrasonic Abrasive Removal Of EDM Recast  

NASA Technical Reports Server (NTRS)

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.

Mandel, Johnny L.; Jacobson, Marlowe S.

1990-01-01

48

Assessment of abrasion-assisted material removal in wire EDM  

Microsoft Academic Search

Machining speed and surface integrity continue to be issues of focus in current wire EDM research. In this light, the proof-of-concept of a hybrid wire EDM process that utilizes a wire embedded with electrically non-conducting abrasives is presented. Material removal in this novel process is realized through electrical erosion that is augmented by two-body abrasion. This is shown to bring

I. Menzies; P. Koshy

2008-01-01

49

Recast layer removal after electrical discharge machining via Taguchi analysis: A feasibility study  

Microsoft Academic Search

This study explores the feasibility of removing the recast layer (RCL) using etching and mechanical grinding for Ni-based superalloy materials by means of electrical discharge machining (EDM). The EDM process is widely used for machining hard metals and performing specific tasks that cannot be achieved using conventional techniques. The sparks produced during the EDM process melt the metal's surface, which

Che-Chung Wang; Han-Ming Chow; Lieh-Dai Yang; Chun-Te Lu

2009-01-01

50

Autonomous Process Planning with Real-Time Machining for Productive Sculptured Surface Manufacturing Based on Automatic Recognition of Geometric Features  

Microsoft Academic Search

The paper deals with a study on technologies to enhance the manufacturing productivity of a product consisting of sculptured surfaces. A process planning system coupled with real time machining is proposed such that the productive machining plan and tool motion can automatically be generated once available resources and machining know-how are given for the metal cutting-EDM mixed environment. The system

Kazuo Yamazaki; Yasuhiro Kawahara; Jieh-Chian Jeng; Hideki Aoyama

1995-01-01

51

Statistical analysis on electrode wear in EDM of tool steel DIN 1.2714 used in forging dies  

Microsoft Academic Search

Electrical discharge machining (EDM) is a widespread process which works very effectively in machining of difficult-to-cut materials and alloys in die and aerospace industries with high dimensional accuracies. However, this capability could be deteriorated due to electrode wear leading to decrease of process productivity. In this study, the effect of machining parameters of EDM process including on-time, current, voltage, the

H. Zarepour; A. Fadaei Tehrani; D. Karimi; S. Amini

2007-01-01

52

Fiber optic diagnostic techniques for the electrical discharge machining process  

E-print Network

were used along with current pulse waveforms from the EDM machine to study the temporal characteristics of the spark. During this experiment an optical pattern was identified that indicated when an arc was being formed in the EDM machine instead of a...

Pillans, Brandon William

2012-06-07

53

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

SciTech Connect

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.

Mitra, S.; Paul, G.; Sarkar, S. [Department of Production Engineering, Jadavpur University, Kolkata-700032 (India); Nagahanumaiah [Micro Systems Technology Laboratory, CMERI, Durgapur (India)

2011-01-17

54

A Study on Machinability of B-Modified Ti6Al4V Alloys by EDM  

Microsoft Academic Search

The effect of microstructural refinement and presence of TiB particles on the electrical discharge machinability of hypoeutectic B-modified Ti-6Al-4V alloys have been studied. This has been characterized on the basis of changes in the following machining responses: material removal rate and tool wear rate. Material removal rate remains unaffected by B addition to Ti-6Al-4V because of insignificant changes in hardness

Indrani Sen; G. Karthikeyan; J. Ramkumar; R. Balasubramaniam

2012-01-01

55

A Study on Machinability of B-Modified Ti6Al4V Alloys by EDM  

Microsoft Academic Search

The effect of microstructural refinement and presence of TiB particles on the electrical discharge machinability of hypoeutectic B-modified Ti-6Al-4V alloys have been studied. This has been characterized on the basis of changes in the following machining responses: materials removal rate and tool wear rate. Materials removal rate remain unaffected by B addition to Ti-6Al-4V owing to insignificant changes in hardness

Indrani Sen; G. Karthikeyan; J. Ramkumar; R. Balasubramaniam

2011-01-01

56

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

SciTech Connect

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.

Piscotty, M. A., LLNL

1997-08-01

57

Model of workpiece erosion for electrical discharge machining process  

NASA Astrophysics Data System (ADS)

The previously published step-wise model (SWM) of cold electrodes erosion of electric arc heaters (EAHs) was modified for the calculation of workpiece removal rate (WRR) in electrical discharge machining (EDM) process. Modified model applies both relations the step-wise erosion model and the point heat source erosion model and takes into account the discharge current, the discharge pulse/pause time and thermophysical properties of machined material. The results of calculations show a reasonable agreement with data obtained experimentally by different authors about different materials and conditions.

Sharakhovsky, Leonid I.; Marotta, Aruy; Essiptchouk, Alexei M.

2006-11-01

58

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

NASA Astrophysics Data System (ADS)

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.

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

2014-01-01

59

The EDM surface: Topography, chemistry, and metallurgy  

SciTech Connect

The surface created by the electric discharge machining (EDM) process is of special interest because it has been shown to have a negative effect on the fatigue properties of many alloys. An understanding of the surface metallurgy and chemistry is important in predicting those alloys which are most susceptible to failure. Remedial actions, including thickness minimization, alteration, or removal of the surface layer are addressed.

Fuller, J.E.

1991-01-01

60

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

NASA Astrophysics Data System (ADS)

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.

Choudhary, Rajesh; Kumar, Harmesh; Singh, Shankar

2013-12-01

61

Research Developments in Additives Mixed Electrical Discharge Machining (AEDM): A State of Art Review  

Microsoft Academic Search

Electrical discharge machining (EDM) is a well-established modern machining process used to manufacture geometrically complex shapes, process hard materials that are extremely difficult to machine by conventional machining processes. This noncontact machining technique is continuously emerging from a mere tool and dies making process to a microscale machining applications. In recent years, researches have emphasized on increasing machining performance coupled

Anil Kumar; Sachin Maheshwari; Chitra Sharma; Naveen Beri

2010-01-01

62

Modeling and analysis of electrode wear and white layer thickness in die-sinking EDM process through response surface methodology  

Microsoft Academic Search

In this study, an attempt has been made to model electrode wear (EW) and recast layer thickness (WLT) through response surface\\u000a methodology (RSM) in a die-sinking EDM process. A central composite rotatable design (CCRD) involving three variables with\\u000a five levels has been employed to establish a mathematical model between input parameters and responses. Pulse on-time, pulse\\u000a off-time and pulse current

Ula? Çayda?; Ahmet Hasçalik

2008-01-01

63

Monitoring of Ultraprecision Machining Processes  

Microsoft Academic Search

New demands are being placed on monitoring systems in the manufacturing environment because of recent developments in machining technology and machine tool design. In-process sensors are used to generate control signals to improve both the control and productivity of manufacturing systems. Numerous different sensors are available for monitoring and controlling the machining environment including force, power, and acoustic emission (AE)

D. A. Dornfeld; Y. Lee; A. Chang

2003-01-01

64

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

NASA Astrophysics Data System (ADS)

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.

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

2014-07-01

65

Wear-resist Electrodes for Micro-EDM  

Microsoft Academic Search

This article proposes a new type of electrode for micro-electro-discharge machining (micro-EDM), which can produce ultra fine micro components from various kinds of materials including those that cannot be processed by the silicon or the Lithographie Galvanoformung Abformung (LIGA) processings. This electrode is made by way of the electrodeposition process on the basis of the difference between the discharging performance

Wang Yuangang; Zhao Fuling; Wang Jin

2009-01-01

66

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

NASA Astrophysics Data System (ADS)

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.

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

2015-01-01

67

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

NASA Astrophysics Data System (ADS)

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.

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

2009-11-01

68

The electro-discharge machining surfaces of high-chromium white irons  

Microsoft Academic Search

Electro-discharge machining (EDM) is widely used with hard and brittle materials, which are difficult to machine using conventional techniques. In the EDM process, spark discharges between the electrically conductive workpiece and a tool electrode increase the temperature so that localized melting occurs. Approximately 15% of this molten metal is removed by flushing, while the remainder resolidifies on the workpiece surface

C. P. Tabrett

1996-01-01

69

Solutions for technological performances increasing at ultrasonic aided electrodischarge machining  

Microsoft Academic Search

The paper deals with researches concerning phenomenology and solutions for technological parameters improvement at finishing\\u000a through electrodischarge machining (EDM) aided by ultrasonic (US) longitudinal vibrations of electrode-tool (EDM + US). The\\u000a stability of EDM + US finishing process was obtained increasing the working gap through ignition voltage growing and amplitude\\u000a decrease of US oscillations. Pulse energy minimization aimed to reduce

N. I. Marinescu; D. Ghiculescu; G. Jitianu

2009-01-01

70

Electrical discharge machining of TiNiCr and TiNiZr ternary shape memory alloys  

Microsoft Academic Search

This study investigates the influence of the machining characteristics on TiNiX ternary shape memory alloys (SMAs) using electro-discharge machining (EDM). Experimental results show that the material removal rates (MRRs) of Ti50Ni49.5Cr0.5 and Ti35.5Ni49.5Zr15 alloys in the EDM process exhibit a reverse relationship to the product of the alloy's melting temperature and thermal conductivity. The surface roughness (Ra) of the EDMed

S. L. Chen; S. F. Hsieh; H. C. Lin; M. H. Lin; J. S. Huang

2007-01-01

71

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

SciTech Connect

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.

Miller, Scott F. [University of Michigan; Kao, Chen C. [University of Michigan; Shih, Albert J. [University of Michigan; Qu, Jun [ORNL

2005-01-01

72

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

PubMed Central

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

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

2014-01-01

73

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

PubMed

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

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

2014-01-01

74

Plasma characterization of dry ?-EDM  

Microsoft Academic Search

An attempt was made to characterize the dry microelectric discharge machining (?-EDM) plasma systematically by using optical\\u000a emission spectroscopy. In order to characterize the plasma and its parameters such as plasma temperature, electron density,\\u000a Debye length, and gamma parameter, the optical spectra were recorded for different energies and with different diameters of\\u000a tool electrode. From the recorded spectra, using line

S. Kanmani Subbu; G. Karthikeyan; J. Ramkumar; S. Dhamodaran

2011-01-01

75

High-speed micro-electro-discharge machining.  

SciTech Connect

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.

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

76

Multi-Objective Optimization of Green EDM: An Integrated Theory  

NASA Astrophysics Data System (ADS)

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 ?s), dielectric level (80 mm) and flushing pressure (0.3 kg/cm2).

Jagadish; Ray, A.

2015-01-01

77

EDM performance of Cr\\/Cu-based composite electrodes  

Microsoft Academic Search

Electrode materials for electrical discharge machining (EDM) are usually graphite, copper and copper alloys because these materials have high melting temperature, and excellent electrical and thermal conductivity. The electrodes made by using powder metallurgy technology from special powders have been used to modify EDM surfaces in recent years, to improve wear and corrosion resistance. However, electrodes are normally fabricated at

H. C Tsai; B. H Yan; F. Y Huang

2003-01-01

78

A comparative experimental investigation of deep-hole micro-EDM drilling capability for cemented carbide (WC-Co) against austenitic stainless steel (SUS 304)  

Microsoft Academic Search

Microelectro-discharge machining (micro-EDM) has become a widely accepted non-traditional material removal process for machining\\u000a difficult-to-cut but conductive materials effectively and economically. The present study aims to investigate the feasibility\\u000a of machining deep microholes in two difficult-to-cut materials: cemented carbide (WC-Co) and austenitic stainless steel (SUS\\u000a 304) using the micro-EDM drilling. The effect of discharge energy and electro-thermal material properties on

Muhammad Pervej Jahan; Yoke San Wong; Mustafizur Rahman

2010-01-01

79

An Experimental Study on Electrical Discharge Machining of Manganese–Zinc Ferrite Magnetic Material  

Microsoft Academic Search

The objective of this research is to investigate the machining characteristics of manganese–zinc (Mn–Zn) ferrite magnetic material using electrical-discharge machining (EDM). The material removal rate, the surface topography, the surface roughness, the recast layer, and the chemical composition of the machined surface were studied in terms of EDM processing variables. Experimental results indicate that the morphology of debris revealed the

Y. H. Guu; Kuan-Lin Tsai; Lin-Ke Chen

2007-01-01

80

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

PubMed Central

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 ?·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 ?·cm is obviously different from that with the electrical resistivity lower than 687 ?·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

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

2014-01-01

81

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

PubMed

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 ?·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 ?·cm is obviously different from that with the electrical resistivity lower than 687 ?·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

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

2014-01-01

82

Effect of Deep Cryogenic Treatment on Machinability of Titanium Alloy (Ti6246) in Electric Discharge Drilling  

Microsoft Academic Search

Currently there is a vital need for cost effective machining processes for titanium alloys. Electrical discharge machining (EDM) is used quite extensively in machining titanium alloys due to its favorable features and advantages. This paper investigates the effect of deep cryogenic treatment (DCT) on machinability of Ti 6246 alloy in electric discharge drilling (EDD) by conducting experimental investigations on the

Simranpreet Singh Gill; Jagdev Singh

2010-01-01

83

Development of the Cylindrical Wire Electrical Discharge Machining Process, Part 2: Surface Integrity and Roundness  

Microsoft Academic Search

This study investigates the surface integrity and roundness of parts created by the cylin- drical wire EDM process. A mathematical model for the arithmetic average surface roughness on the ideal surface of a cylindrical wire EDM workpiece is first derived. Effects of wire feed rate and part rotational speed on the surface finish and roundness for brass and carbide work-materials

Jun Qu; Albert J. Shih; Ronald O. Scattergood

2002-01-01

84

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

NASA Astrophysics Data System (ADS)

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.

Punturat, Jiraporn; Tangwarodomnukun, Viboon; Dumkum, Chaiya

2014-11-01

85

Electrical discharge machining of a NiAlFe ternary shape memory alloy  

Microsoft Academic Search

The electro-discharge machining (EDM) characteristics of a NiAlFe ternary shape memory alloy (SMA) have been investigated in this study. Experimental results reveal that the material removal rates (MRRs) of Ni60Al24.5Fe15.5 and Ti35.5Ni49.5Zr15 alloys in the EDM process exhibit a reverse relationship to the product of the alloy's melting temperature and thermal conductivity. In addition, a precise EDM machining of NiAlFe

S. L. Chen; S. F. Hsieh; H. C. Lin; M. H. Lin; J. S. Huang

2008-01-01

86

Intelligent process supervision for predicting tool wear in machining processes  

Microsoft Academic Search

An intelligent supervisory system supported on a model-based approach is presented herein. The application for predicting tool wear in machining processes is selected as a case study. A model created using artificial neural networks and able to predict the process output is introduced as a means of dealing with the characteristics of such an ill-defined process as machining. This model

Rodolfo E Haber; A Alique

2003-01-01

87

Some investigations into the electric discharge machining of hardened tool steel using different electrode materials  

Microsoft Academic Search

Electric discharge machining (EDM), a ‘non-traditional machining process’, has been replacing drilling, milling, grinding and other traditional machining operations and is now a well-established machining option in many manufacturing industries throughout the world. Modern ED machinery is capable of machining geometrically complex or hard material components, that are precise and difficult-to-machine such as heat treated tool steels, composites, super alloys,

Shankar Singh; S. Maheshwari; P. C. Pandey

2004-01-01

88

Novel power supply topology for large working gap dry EDM  

Microsoft Academic Search

For material removal in rotor balancing machines, dry Electrical Discharge Machining (EDM) with large working gap is an advantageous alternative to the common mechanical drilling, grinding or laser drilling. This paper presents a novel topology of a power supply required for such an application. It has an increased ignition voltage capability of up to 10 kV compared to standard power

A. Looser; L. Linares; C. Zwyssig; J. W. Kolar

2010-01-01

89

Effect of ultrasonic-assisted EDM on the surface integrity of cemented tungsten carbide (WC-Co)  

Microsoft Academic Search

This paper studies the effects of tool electrode ultrasonic vibration on some surface integrity properties of cemented tungsten\\u000a carbide (WC-10%Co) in the electrical discharge machining (EDM) process. Surface integrity concerns surface alterations associated\\u000a with a manufacturing process, including surface topography, surface metallurgy, and changes of the mechanical and physical\\u000a properties of the material as well as residual stresses. Scanning electron

Amir Abdullah; Mohammad R. Shabgard; A. Ivanov; Mohammad T. Shervanyi-Tabar

2009-01-01

90

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

NASA Astrophysics Data System (ADS)

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-?m 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.

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

2014-04-01

91

Gaussian Processes For Machine Learning  

Microsoft Academic Search

Gaussian processes (GPs) are natural generalisations of multivariate Gaussian ran- dom variables to innite (countably or continuous) index sets. GPs have been applied in a large number of elds to a diverse range of ends, and very many deep theoretical anal- yses of various properties are available. This paper gives an introduction to Gaussian processes on a fairly elementary level

Matthias Seeger

2004-01-01

92

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

PubMed

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

Stráský, Josef; Jane?ek, Miloš; Harcuba, Petr; Bukovina, Michal; Wagner, Lothar

2011-11-01

93

EFFECTS OF WORKPIECE ROTATION ON MACHINABILITY DURING ELECTRICAL-DISCHARGE MACHINING  

Microsoft Academic Search

This work presents a novel rotary (EDM) electrical-discharge machining cutting process for a hard-to-machine cylindrical workpiece. An experimental analysis was carried out on an AISI D2 tool steel with a copper electrode. The effects of machining parameters such as pulsed current, pulse on-time, and workpiece rotation on material removal rate and surface roughness were analyzed. These effects were compared with

Y. H. Guu; H. Hocheng

2001-01-01

94

Study of micro-EDM plasmas  

NASA Astrophysics Data System (ADS)

Micro Electrical Discharge Machining (micro-EDM) is a plasma-assisted process for the manufacturing of micro-components in high-hardness conductive materials. The removal of material is the result of a sum of dc discharges, produced within a point to plane system of electrodes immersed in a dielectric fluid, whose electric disruption with the development of plasma-currents can be induced by imposing a threshold voltage. To better understand the interaction between the micro-plasma and the material, we have designed and build an experimental setup for the production of single-discharges, characterized by a constant voltage-current operation point. The device allows the ignition of resistive plasmas in air/water at different pulse-times (˜100--3200 ?s), currents (˜1-20 A for ˜75-250 V), polarities and gap-sizes (˜0,5-25 ?m), and the changes in these work conditions can be correlated to the type and size of the craters produced. The micro-plasma electron density ne is measured using the Stark broadening of the H? atomic line. First results give ne ˜ 10^16 -- 10^17 cm^3, in agreement with estimates obtained from an electrical circuit model of the discharge.

Braganca, I. M. F.; Rosa, P. A. R.; Dias, F. M.; Alves, L. L.

2011-11-01

95

Machining piezoelectric (PZT) ceramics using an electrochemical spark machining (ECSM) process  

Microsoft Academic Search

Machining of advanced engineering materials such as composites and ceramics is important but it is very difficult and uneconomical to do so by conventional methods of machining. A need for new techniques for machining these advanced engineering materials cannot be over-emphasized. In this study, the authors have attempted to explore the feasibility of using an electrochemical spark machining (ECSM) process

Y. P. Singh; Vijay K. Jain; Prashant Kumar; D. C. Agrawal

1996-01-01

96

Optimization of control parameters for SR in EDM injection flushing type on stainless steel 304 workpiece  

NASA Astrophysics Data System (ADS)

The operating control parameters of injection flushing type of electrical discharge machining process on stainless steel 304 workpiece with copper tools are being optimized according to its individual machining characteristic i.e. surface roughness (SR). Higher SR during EDM machining process results for poor surface integrity of the workpiece. Hence, the quality characteristic for SR is set to lower-the-better to achieve the optimum surface integrity. Taguchi method has been used for the construction, layout and analysis of the experiment for each of the machining characteristic for the SR. The use of Taguchi method in the experiment saves a lot of time and cost of machining the experiment samples. Therefore, an L18 Orthogonal array which was the fundamental component in the statistical design of experiments has been used to plan the experiments and Analysis of Variance (ANOVA) is used to determine the optimum machining parameters for this machining characteristic. The control parameters selected for this optimization experiments are polarity, pulse on duration, discharge current, discharge voltage, machining depth, machining diameter and dielectric liquid pressure. The result had shown that the lower the machining diameter, the lower will be the SR.

Reza, M. S.; Yusoff, A. R.; Shaharun, M. A.

2012-09-01

97

Effect of electrical discharge machining on surface characteristics and machining damage of AISI D2 tool steel  

Microsoft Academic Search

In this work the electrical discharge machining (EDM) of AISI D2 tool steel was investigated. The surface characteristics and machining damage caused by EDM were studied in terms of machining parameters. Based on the experimental data, an empirical model of the tool steel was also proposed. A new damage variable was used to study the EDM damage. The workpiece surface

Y. H. Guu; H. Hocheng; C. Y. Chou; C. S. Deng

2003-01-01

98

Electric discharge machining of Al–10%SiC P as-cast metal matrix composites  

Microsoft Academic Search

The use of unconventional machining techniques in shaping aluminium metal matrix composites (Al-MMC) has generated considerable interest as the manufacturing of complicated die contours in these hard materials to a high degree of accuracy and surface finish is difficult. Electrical discharge machining (EDM) is an important process for machining difficult-to-machine materials like metal matrix composites. Among the many unconventional processing

P. Narender Singh; K. Raghukandan; M. Rathinasabapathi; B. C. Pai

2004-01-01

99

Fabrication of a micro-spherical tool in EDM combined with Ni-diamond co-deposition  

NASA Astrophysics Data System (ADS)

This paper demonstrates a novel fabrication process using electro-discharge-machining (EDM) combined with co-deposited Ni-diamond composites to build a unique micro-spherical diamond tool. A micro tool is made by a hybrid process including wire electro-discharge grinding, EDM spherical forming, electrochemical machining and co-deposition. Tungsten carbide material is used as the tool substrate. The influence of EDM spherical forming and co-deposition parameters on the tool geometry is presented. The experimental result shows a unique micro-spherical diamond tool can be successfully built with suitable spherical forming parameters that are a peak current of 3 A, pulse duration of 40 µs and spindle rotational speed of 0 rpm in the air, and in Ni-diamond co-deposition are a current density of 7 A dm-2, diamond particle size of 3 µm, diamond particle concentration of 10 g l-1 and rotational speed of 15 rpm. When using this method, the micro tool has a better geometric shape, uniform particle distribution and suitable particle adhesion quantity. The tool is tested to machine a mold provided with a micro-spherical cavity in a high nickel alloy.

Hung, Jung-Chou; Lien, Shao-Chun; Lin, Jui-Kuan; Huang, Fuang-Yuan; Yan, Biing-Hwa

2008-04-01

100

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)

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.

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

1980-01-01

101

Characterisation of integrated WAAM and machining processes  

NASA Astrophysics Data System (ADS)

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..

Adebayo, Adeyinka

102

Artificial Neural Network Prediction of Material Removal Rate in Electro Discharge Machining  

Microsoft Academic Search

Thermal erosion theory is widely accepted as an explanation of the erosion process in electro-discharge machining (EDM). Theoretical models are based on the solution of the transient heat conduction equation, which is modeled considering suitable assumptions with appropriate initial and boundary conditions. The closed form solutions result only after considering too many assumptions, which are far from actual machining conditions.

Deepak Kumar Panda; Rajat Kumar Bhoi

2005-01-01

103

Micro Electro Discharge Machining of Electrically Nonconductive Ceramics  

SciTech Connect

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.

Schubert, A. [Chair Micromanufacturing Technology, Faculty of Mechanical Engineering, Chemnitz University of Technology, 09107 Chemnitz (Germany); Fraunhofer Institute for Machine Tools and Forming Technology IWU, 09126 Chemnitz (Germany); Zeidler, H.; Hackert, M. [Chair Micromanufacturing Technology, Faculty of Mechanical Engineering, Chemnitz University of Technology, 09107 Chemnitz (Germany); Wolf, N. [Fraunhofer Institute for Machine Tools and Forming Technology IWU, 09126 Chemnitz (Germany)

2011-05-04

104

Micro Electro Discharge Machining of Electrically Nonconductive Ceramics  

NASA Astrophysics Data System (ADS)

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 ?m 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.

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

2011-05-01

105

Optical processing architectures for machine vision functions  

NASA Astrophysics Data System (ADS)

Manufacturers must increase production rates and simultaneously tighten quality/process controls in order to meet ever-increasing competition and consumer demands for high quality products. This requires that products be manufactured more efficiently, at reducing cost, and with minimum scrap/waste. This in turn demands higher-speed inspection, with higher accuracy and consistency as well as intelligence. Achieving these goals will require highly parallel systems that perform image processing and pattern recognition in real time in various manufacturing environments. This paper presents a hybrid architecture combining state-of-the- art optical processing with conventional digital processing. A Solid Optical Correlator (SOC) system has been built and validated. The SOC incorporates rigidity, stability, and manufacturability--attributes which facilitate the use of the optical correlator in real-world industrial machine vision applications.

Brasher, James D.; Hester, Charles F.; Kinser, Jason M.; Selzer, Fred J.; Temmen, Mark G.

1992-03-01

106

Electrical-Discharge Machining With Additional Axis  

NASA Technical Reports Server (NTRS)

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.

Malinzak, Roger M.; Booth, Gary N.

1991-01-01

107

Co-option of EDM2 to distinct regulatory modules in Arabidopsis thaliana development  

PubMed Central

Background Strong immunity of plants to pathogenic microorganisms is often mediated by highly specific mechanisms of non-self recognition that are dependent on disease resistance (R) genes. The Arabidopsis thaliana protein EDM2 is required for immunity mediated by the R gene RPP7. EDM2 is nuclear localized and contains typical features of transcriptional and epigenetic regulators. In addition, to its role in immunity, EDM2 plays also a role in promoting floral transition. This developmental function of EDM2, but not its role in RPP7-mediated disease resistance, seems to involve the protein kinase WNK8, which physically interacts with EDM2 in nuclei. Results Here we report that EDM2 affects additional developmental processes which include the formation of leaf pavement cells and leaf expansion as well as the development of morphological features related to vegetative phase change. EDM2 has a promoting effect of each of these processes. While WNK8 seems not to exhibit any vegetative phase change-related function, it has a promoting effect on the development of leaf pavement cells and leaf expansion. Microarray data further support regulatory interactions between WNK8 and EDM2. The fact that the effects of EDM2 and WNK8 on leaf pavement cell formation and leaf expansion are co-directional, while WNK8 counteracts the promoting effect of EDM2 on floral transition, is surprising and suggests that WNK8 can modulate the activity of EDM2. Conclusion We propose that EDM2 has been co-opted to distinct regulatory modules controlling a set of different processes in plant immunity and development. WNK8 appears to modulate some functions of EDM2. PMID:20840782

2010-01-01

108

Flexible human machine interface for process diagnostics  

SciTech Connect

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.

Reifman, J.; Graham, G.E.; Wei, T.Y.C. [Argonne National Lab., IL (United States); Brown, K.R.; Chin, R.Y. [ComEd Chicago, IL (United States)

1996-05-01

109

Improving Electrical Discharge Machined Surfaces Using Magnetic Abrasive Finishing  

Microsoft Academic Search

A recast layer is invariably present on surfaces produced by electrical discharge machining (EDM). For some metals with high hardness, the recast layer may contain micro-cracks. This damaged layer can affect the service life of the parts produced by this method. This investigation demonstrates that magnetic abrasive finishing (MAF) process using unbonded magnetic abrasives (UMA), can improve the quality of

Biing-Hwa Yan; Geeng-Wei Chang; Jung-Hsien Chang; Rong-Tzong Hsu

2004-01-01

110

Wire-cut electrical discharge machinability of ceramics. Final report  

SciTech Connect

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.

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

1987-09-01

111

In-process control of machining. Phase 1: Milling  

NASA Astrophysics Data System (ADS)

A system to control the path of a milling cutter was developed, integrated with a machining center, and demonstrated. Feedback control was based on measurements of machined edge coordinates taken behind the cutter. The demonstration consisted of milling four, parallel, identical, teardrop-shaped openings, spaced 90 degrees apart through the wall of an orifice tube. A linear diode array, sensitive to reflected light, was used to locate and record the edge profile of each opening. Real-time tool path redirection was based on a continual analysis of generated orifice area accumulation, thereby basing control of the machining process on area, the parameter which best reflected the function of the part. After the machining was completed, the optical edge sensor was used to inspect the part before it was removed from the machine. These processes resulted in significant improvements in productivity and quality.

McCabe, J. T.; Albrecht, P. A.; Locke, D.; Kirschbaum, R. A.

1985-09-01

112

Simulation of Fatigue Crack Initiation at Corrosion Pits With EDM Notches  

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

113

A neural network process model for abrasive flow machining operations  

Microsoft Academic Search

This paper describes the development of a predictive process modeling system for the abrasive flow machining (AFM) process. This process is used for polishing and surface removal of workpieces with an internal flow path. The core of the process modeling system is a set of neural network models that predicts surface finish and dimensional change. These neural network models are

Kimberly L. Petri; Richard E. Billo; Bopaya Bidanda

1998-01-01

114

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

PubMed

This paper reports electrochemical polishing (EP) of 316L stainless-steel structures patterned using micro-electro-discharge machining (?EDM) for application to stents including intelligent stents based on micro-electro-mechanical-systems technologies. For the process optimization, 10 ?m deep cavities ?EDMed 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 ?EDM. The EP of ?EDMed 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 ?EDMed surfaces before and after EP. A custom rotational apparatus was used to polish tubular test samples including stent-like structures created using ?EDM, demonstrating uniform removal of surface roughness and sharp edges from the structures. PMID:22183790

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

2012-02-01

115

Embedded Machine Learning Systems for Natural Language Processing: A General  

E-print Network

Embedded Machine Learning Systems for Natural Language Processing: A General Framework Claire for Natural Language Processing, Lecture Notes in Artificial Intelligence, 315­328, Springer, 1996. Abstract. This paper presents Kenmore, a general framework for knowl­ edge acquisition for natural language processing

Cardie, Claire

116

The fabrication of a micro-spiral structure using EDM deposition in the air  

NASA Astrophysics Data System (ADS)

A novel micromachining method to deposit a micro-3D spiral structure in air using electrical discharge machining (EDM) with a brass electrode was presented. During the deposition process, a 3D spiral structure is obtained only by the feed of the z-axis in the vertical direction. Furthermore, the obtained structure can be formed and repeated stably even in the upside-down direction under a gravity environment. It is seen that the material components of a micro-spiral structure are almost the same as those of an electrode by the energy spectrum analysis of a micro-spiral structure. According to scanning electron microscope photographs, the micro-spiral appears to feature a layered material organism structure and has compact bonding with the body material. In order to understand the forming mechanism of this kind of micro-spiral structure, simulation analysis is conducted. The track of the deposition particles can be obtained by simulation, which determines the shape of the deposited structure. According to the simulation results, the track of the deposition particles is consistent with that of EDM experiments. It is further found that the distribution of the electromagnetic field in a discharge channel has an important influence on the deposited structure and the track of the deposition particles.

Chi, Guanxin; Wang, Zhenlong; Xiao, K.; Cui, Jingzhi; Jin, Baidong

2008-03-01

117

A study on the fine-finish die-sinking micro-EDM of tungsten carbide using different electrode materials  

Microsoft Academic Search

In recent years, tungsten carbide (WC) and its composites (WC–Co) are widely used in the die and mold industries due to their unique combination of hardness, strength and wear resistance. Micro-EDM is one of the most effective methods for machining these extremely difficult-to-cut materials. However, numerous applications of WC often involve intense mechanical demands at the surface. Therefore, fine-finish micro-EDM

M. P. Jahan; Y. S. Wong; M. Rahman

2009-01-01

118

Electrochemical machining in-process data collection and control  

SciTech Connect

Electrochemical machining (ECM) is a fast and efficient method to fabricate intricate metal parts. However, tooling is often expensive; and electical power consumption is relatively high. The precision of an ECM process is dependent upon several variables which often cannot be predicted in the initial tool design. This leads to iterative tool adjustments until the desired level of precision is achieved. A system was devised to use a computer for collecting data from the ECM process and for monitoring and controlling ECM operations. It is believed that these data collections and analyses will lead to the formulation of algorithms to produce parts with better tolerances and will allow more efficient uses of the ECM machines. One algorithm has been developed to allow the efficient ECM of large-surface-area parts. Such programs and equipment will enhance the competitive position of the ECM process in machining applications previously performed by more conventional methods while minimizing electrical power consumption.

Neal, R.E.

1980-09-01

119

Controlled English to facilitate human/machine analytical processing  

NASA Astrophysics Data System (ADS)

Controlled English is a human-readable information representation format that is implemented using a restricted subset of the English language, but which is unambiguous and directly accessible by simple machine processes. We have been researching the capabilities of CE in a number of contexts, and exploring the degree to which a flexible and more human-friendly information representation format could aid the intelligence analyst in a multi-agent collaborative operational environment; especially in cases where the agents are a mixture of other human users and machine processes aimed at assisting the human users. CE itself is built upon a formal logic basis, but allows users to easily specify models for a domain of interest in a human-friendly language. In our research we have been developing an experimental component known as the "CE Store" in which CE information can be quickly and flexibly processed and shared between human and machine agents. The CE Store environment contains a number of specialized machine agents for common processing tasks and also supports execution of logical inference rules that can be defined in the same CE language. This paper outlines the basic architecture of this approach, discusses some of the example machine agents that have been developed, and provides some typical examples of the CE language and the way in which it has been used to support complex analytical tasks on synthetic data sources. We highlight the fusion of human and machine processing supported through the use of the CE language and CE Store environment, and show this environment with examples of highly dynamic extensions to the model(s) and integration between different user-defined models in a collaborative setting.

Braines, Dave; Mott, David; Laws, Simon; de Mel, Geeth; Pham, Tien

2013-06-01

120

Sequential Laser and EDM Micro-drilling for Next Generation Fuel Injection Nozzle Manufacture  

Microsoft Academic Search

High quality holes of diameters less than 145 ?m are required for the manufacture of next generation diesel fuel injection nozzles for improved combustion efficiency and reduction of emission to the environment. The current practice of using electro-discharge machining (EDM) drilling of fuel injection nozzles is limited in terms of the hole size it can produce effectively and the length

Lin Li; C. Diver; J. Atkinson; R. Giedl-Wagner; H. J. Helml

2006-01-01

121

A novel approach for batch production of micro holes by micro EDM  

Microsoft Academic Search

The paper proposed a novel approach of effective production of mass micro holes. A set of micro w-EDM mechanism is designed and mounted on the developed tabletop precision machine tool. The tension of micro wire is precisely controlled by magnetic force. In addition, the micro vibrations of the wire during discharging are effectively suppressed by the developed vibration suppression system.

S. T. Chen; Y. S. Liao

122

Department of Biological Engineering Spring 2013 Baobab Processing Machine  

E-print Network

PENNSTATE Department of Biological Engineering Spring 2013 Baobab Processing Machine Overview The pulp of the baobab fruit is rich in nutritional value and has a high economic value for small villages needs for the new design were obtained from the Coopérative Agricole Le Baobab in Benin where

Demirel, Melik C.

123

Towards Improved Prediction of Ocean Processes Using Statistical Machine Learning  

E-print Network

in the Southern California Bight region predicted by Regional Ocean Modeling Systems (ROMS) [3]. We propose dataTowards Improved Prediction of Ocean Processes Using Statistical Machine Learning Geoffrey A of predicting ocean cur- rents based on historical data and ocean models. This problem is relevant to navigation

Sukhatme, Gaurav S.

124

Energy Distribution Ratio into Micro EDM Electrodes  

NASA Astrophysics Data System (ADS)

Energy distribution ratio into micro EDM electrodes was determined based on the summation between the ratio of energy loss due to heat conduction within electrodes and ratio of energy carried away by debris. Ratio of energy loss due to heat conduction was obtained by comparing the measured and calculated temperature rise on electrode after igniting plural pulses discharges. On the other hand, the ratio of energy carried away by debris was calculated based on the measured removal volume. Energy distribution ratio into micro EDM anode and cathode was between 10% and 15% in total which was comparatively lower than that of macro EDM. This is because much larger fraction of the total discharge energy is consumed for the generation and enthalphy increase of the plasma in the early stage of discharge. Besides, unlike macro EDM the energy carried away by debris in micro EDM cannot be ignored compared with the energy lost due to heat conduction. This means, the energy consumption by material removal in micro EDM with regard to the energy distributed into the electrodes is more efficient compared to that of macro EDM.

Zahiruddin, Mohd; Kunieda, Masanori

125

Implementing a grolishing process in Zeeko IRP machines.  

PubMed

The removal of mid-spatial-frequency errors is a challenging issue in most subaperture polishing technologies. A novel "grolishing" technology has been developed to deal with grinding errors of spatial wavelengths from 1 to 50 mm with the help of power spectral density analysis and filter theory. This grolishing process was implemented on Zeeko's IRP polishing machine, on which all the subsequent polishing was performed. This has greatly reduced the process time. Although different abrasive have been used, the process is self-contained. The process parameters have been optimized to leave an edge upstand of peak-to-valley of 1 ?m over a width of 40 mm. PMID:23033036

Yu, Guoyu; Walker, David; Li, Hongyu

2012-09-20

126

MATERIAL PROCESSING FOR SELF-ASSEMBLING MACHINE SYSTEMS  

SciTech Connect

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.

K. LACKNER; D. BUTT; C. WENDT

1999-06-01

127

Effects of flushing on electro-discharge machined surfaces  

Microsoft Academic Search

Although the influence of flushing on the efficiency and stability of machining conditions in EDM has been extensively investigated, including the effects of the flushing configuration on the wear of the tool and the profile of the workpiece, little has been reported concerning the effects of flushing on the integrity of the electro-discharge machined (EDMed) surfaces. This paper presents the

Y. S. Wong; L. C. Lim; L. C. Lee

1995-01-01

128

Effect of near-surface residual stress and microstructure modification from machining on the fatigue endurance of a tool steel  

Microsoft Academic Search

This study concerns the effect of machining on the fatigue life of an EN X155CrMoV12 tool steel (SAE J438b), with regard to\\u000a the generation of near-surface residual stress and microstructural modification of the machined surface. Two possible methods\\u000a for machining tool steels were compared: electro-discharge machining (EDM), a high energy density process, and milling, a\\u000a more conventional cutting process. Particular

F. Ghanem; H. Sidhom; C. Braham; M. E. Fitzpatrick

2002-01-01

129

Six-Axis Electrical-Discharge Machine  

NASA Technical Reports Server (NTRS)

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.

Werner, A. R.

1983-01-01

130

Materials processing and machine applications of bulk HTS  

NASA Astrophysics Data System (ADS)

We report a refrigeration system for rotating machines associated with the enhancement of the trapped magnetic flux of bulk high-temperature superconductor (HTS) field poles. A novel cryogenic system was designed and fabricated. It is composed of a low-loss rotary joint connecting the rotor and a closed-cycle thermosiphon under a GM cryocooler using a refrigerant. Condensed neon gas was adopted as a suitable cryogen for the operation of HTS rotating machines with field poles composed of RE-Ba-Cu-O family materials, where RE is a rare-earth metal. Regarding the materials processing of the bulks HTS, thanks to the addition of magnetic particles to GdBa2Cu3O7 - d (Gd123) bulk superconductors an increase of more than 20% in the trapped magnetic flux density was achieved at liquid nitrogen temperature. Field-pole Gd123 bulks up to 46 mm in diameter were synthesized with the addition of Fe-B alloy magnetic particles and assembled into the synchronous machine rotor to be tested. Successful cooling of the magnetized rotor field poles down to 35 K and low-output-power rotating operation was achieved up to 720 rpm in the test machine with eight field-pole bulks. The present results show a substantial basis for making a prototype system of rotating machinery of applied HTS bulks.

Miki, M.; Felder, B.; Tsuzuki, K.; Xu, Y.; Deng, Z.; Izumi, M.; Hayakawa, H.; Morita, M.; Teshima, H.

2010-12-01

131

Artificial neural networks for machining processes surface roughness modeling  

Microsoft Academic Search

In recent years, several papers on machining processes have focused on the use of artificial neural networks for modeling\\u000a surface roughness. Even in such a specific niche of engineering literature, the papers differ considerably in terms of how\\u000a they define network architectures and validate results, as well as in their training algorithms, error measures, and the like.\\u000a Furthermore, a perusal

Fabricio J. Pontes; João R. Ferreira; Messias B. Silva; Anderson P. Paiva; Pedro Paulo Balestrassi

2010-01-01

132

CNC electrical discharge machining centers  

SciTech Connect

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.

Jaggars, S.R.

1991-10-01

133

Micro slit machining using electro-discharge machining with a modified rotary disk electrode (RDE)  

Microsoft Academic Search

To circumvent the high cost of micro electro-discharge machining (MEDM) with superfine wire, the authors modified a conventional electro-discharge machine (EDM) by fitting a rotating disk as the electrode (RDE). Locating the electrode below the workpiece in the modified RDE-EDM, the debris removal rate was greatly improved. Further, by an improved fixture design to stabilize electrode vibration during machining and

H. M Chow; B. H Yan; F. Y Huang

1999-01-01

134

A study of the impact of machine tool structure on machining processes  

Microsoft Academic Search

This paper deals with parallel kinematics machine (PKM) applications for high speed machining. PKM behaviour is anisotropic, so structural deflection due to cutting loads generates different defects in the machined part, according to tool position and orientation in the workspace. The aim of the present study is the definition of a mechanical workspace where the part is machined to a

H. Chanal; E. Duc; P. Ray

2006-01-01

135

Performance of Process Damping in Machining Titanium Alloys at Low Cutting Speed with Different Helix Tools  

NASA Astrophysics Data System (ADS)

Titanium is a strong, lustrous, corrosion-resistant and transition metal with a silver color to produce strong lightweight alloys for industrial process, automotive, medical instruments and other applications. However, it is very difficult to machine the titanium due to its poor machinability. When machining titanium alloys with the conventional tools, the wear rate of the tool is rapidly accelerate and it is generally difficult to achieve at high cutting speed. In order to get better understanding of machining titanium alloy, the interaction between machining structural system and the cutting process which result in machining instability will be studied. Process damping is a useful phenomenon that can be exploited to improve the limited productivity of low speed machining. In this study, experiments are performed to evaluate the performance of process damping of milling under different tool helix geometries. The results showed that the helix of 42° angle is significantly increase process damping performance in machining titanium alloy.

Shaharun, M. A.; Yusoff, A. R.; Reza, M. S.; Jalal, K. A.

2012-09-01

136

Contamination-Free Electrical-Discharge Machining  

NASA Technical Reports Server (NTRS)

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.

Schmidt, Mark G.

1987-01-01

137

Electrical-Discharge Machining Of Perpendicular Passages  

NASA Technical Reports Server (NTRS)

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.

Malinzak, R. Michael; Booth, Gary N.

1996-01-01

138

A Fast Algorithm for Multi-Machine Scheduling Problems with Jobs of Equal Processing Times  

E-print Network

A Fast Algorithm for Multi-Machine Scheduling Problems with Jobs of Equal Processing Times preemption on m identical machines with given release and deadline times. The goal is to produce a schedule processing time p and needs to be allocated on one of the m identical machines. Jobs are not allowed

Paris-Sud XI, Université de

139

Gaussian Processes for Machine Learning Where Are We, And Where Could We Go?  

E-print Network

Gaussian Processes for Machine Learning Where Are We, And Where Could We Go? Matthias Seeger Max Matthias Seeger (MPI BioKyb) Gaussian Processes for Machine Learning NIPS WS Talk, 10/12/05 1 / 12 #12;Outline 1 Where Are We? What Do We Need in Machine Learning? Key Techniques A General Framework 2 Where

Seeger, Matthias

140

Design and Testing of a Friction Stir Processing Machine for Laboratory Research  

SciTech Connect

This presentation describes the design, fabrication and testing of a friction stir processing machine. The machine is intended to be a flexible research tool for a broad range of friction stir processing studies. The machine design also addresses the need for an affordable, robust design for general laboratory use.

Karen S. Miller; Rodney J. Bitsoi; Eric D. Larsen; Herschel B. Smartt

2006-08-01

141

Robotics and Computer Integrated Manufacturing 18 (2002) 233239 Diagnosis of multi-operational machining processes through  

E-print Network

design information. The virtual machining concept is applied to isolate faults between operations variations from all operations. For example, a machining process could have many operations. At each single for the multi-operational machining process. Mantripragada and Whitney [3] adopted the concept of output

Zhou, Shiyu

142

The Evolutionary Design Model (EDM) for the design of complex engineered systems : Masdar City as a case study  

E-print Network

This thesis develops a framework for constructing an Evolutionary Design Model (EDM) that would enhance the design of complex systems through an efficient process. The framework proposed is generic and suggests a group of ...

Alfaris, Anas (Anas Faris)

2009-01-01

143

Statistical process control (SPC) for coordinate measurement machines  

SciTech Connect

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.

Escher, R.N.

2000-01-04

144

EDM surface effects on the fatigue strength of a 15 vol% SiC p\\/Al metal matrix composite material  

Microsoft Academic Search

The effects of electrical discharge machining (EDM) on the surface quality and subsequent performance of a 15 vol% SiC particulate reinforced A356 Al under monotonic and fatigue loading conditions are investigated. Surface and subsurface conditions after EDM surface sparking of the material were compared with the same material after careful surface polishing. Tensile tests were performed on the as-received material

M. Ramulu; G. Paul; J. Patel

2001-01-01

145

Integrated quality control architecture for multistage machining processes  

NASA Astrophysics Data System (ADS)

To solve problems concerning the process quality prediction control for the multistage machining processes, a integrated quality control architecture is proposed in this paper. First, a hierarchical multiple criteria decision model is established for the key process and the weight matrix method stratified is discussed. Predictive control of the manufacturing quality is not just for on-site monitoring and control layer, control layer in the enterprise, remote monitoring level of quality exists a variety of target predictive control demand, therefore, based on XML to achieve a unified description of manufacturing quality information, and in different source of quality information between agencies to achieve the transfer and sharing. This will predict complex global quality control, analysis and diagnosis data to lay a good foundation to achieve a more practical, open and standardized manufacturing quality with higher levels of information integration system.

Yang, Jie; Liu, Guixiong

2010-12-01

146

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

NASA Astrophysics Data System (ADS)

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.

Goswami, D.; Chakraborty, S.

2014-11-01

147

Metaheuristics to minimise makespan on parallel batch processing machines with dynamic job arrivals  

Microsoft Academic Search

Batch processing machines that can process a group of jobs simultaneously are often encountered in semiconductor manufacturing and metal heat treatment. This research investigates the scheduling problem on parallel batch processing machines in the presence of dynamic job arrivals and non-identical job sizes. The processing time and ready time of a batch are equal to the largest processing time and

Huaping Chen; Bing Du; George Q. Huang

2010-01-01

148

Towards an EDM Measurement in Radium-225  

NASA Astrophysics Data System (ADS)

The existence of an atomic electric dipole moment (EDM) would violate both the time and parity symmetries of nature, and so the measurement of one would give a valuable window into physics beyond the standard model. Here we describe recent progress towards measurement of the EDM of radium-225, which is expected to be abnormally large compared to other species. Neutral cold radium atoms are loaded from a magneto-optic trap into an optical dipole trap (ODT), which is mechanically translated to move the radium into the science region. We then transfer the atoms to a second, standing wave ODT suitable for the EDM measurement. In the near future, we plan to optically pump and observe nuclear spin precession. This research is supported by DOE, Office of Nuclear Physics contract No. DE-AC02-06CH11357.

Dietrich, Matthew; Bailey, K.; Greene, J.; Holt, R.; Kalita, M.; Korsch, W.; Lu, Z.-T.; Mueller, P.; O'Connor, T.; Parker, R.; Singh, J.

2012-06-01

149

New laser machining processes for shape memory alloys  

NASA Astrophysics Data System (ADS)

Due to special material properties, shape memory alloys (SMA) are finding increasing attention in micro system technology. However, only a few processes are available for the machining of miniaturized SMA-components. In this connection, laser material processing offers completely new possibilities. This paper describes the actual status of two projects that are being carried out to qualify new methods to machine SMA components by means of laser radiation. Within one project, the laser material ablation process of miniaturized SMA- components using ultra-short laser pulses (pulse duration: approx. 200 fs) in comparison to conventional laser material ablation is being investigated. Especially for SMA micro- sensors and actuators, it is important to minimize the heat affected zone (HAZ) to maintain the special mechanical properties. Light-microscopic investigations of the grain texture of SMA devices processed with ultra-short laser pulses show that the HAZ can be neglected. Presently, the main goal of the project is to qualify this new processing technique for the micro-structuring of complex SMA micro devices with high precision. Within a second project, investigations are being carried out to realize the induction of the two-way memory effect (TWME) into SMA components using laser radiation. By precisely heating SMA components with laser radiation, local tensions remain near the component surface. In connection with the shape memory effect, these tensions can be used to make the components execute complicated movements. Compared to conventional training methods to induce the TWME, this procedure is faster and easier. Furthermore, higher numbers of thermal cycling are expected because of the low dislocation density in the main part of the component.

Haferkamp, Heinz; Paschko, Stefan; Goede, Martin

2001-04-01

150

An experimental investigation of cylindrical wire electrical discharge turning process  

Microsoft Academic Search

The cylindrical wire electrical discharge turning (CWEDT) process was developed to generate precise cylindrical forms on hard,\\u000a difficult to machine materials. A precise, flexible, and corrosion-resistant submerged rotary spindle was designed and added\\u000a to a conventional five-axis CNC wire electrical discharge machine (EDM) to enable the generation of free-form cylindrical\\u000a geometries. The hardness and strength of the work material are

Mohammad Jafar Haddad; Fereshteh Alihoseini; Mostafa Hadi; Meysam Hadad; Alireza Fadaei Tehrani; Aminollah Mohammadi

2010-01-01

151

A passivated electrode batch \\/spl mu\\/EDM technology for bulk metal transducers and packages  

Microsoft Academic Search

Batch mode micro-electro-discharge machining (muEDM) is a lithography-compatible microfabrication method suitable for making devices from bulk metals, including stainless steel. In high-density patterns, spurious discharges through debris can cause workpiece edge rounding, fast tool wear, and mushroom-shaped metal recasting of the tool. This paper reports a Si coating technique that acts as a discharge barrier on the sidewalls of batch

Mark T. Richardson; Yogesh B. Gianchandani

2005-01-01

152

Material removal rate and electrode wear study on the EDM of silicon carbide  

Microsoft Academic Search

In this work, a material removal rate (MRR) and electrode wear (EW) study on the die-sinking electrical discharge machining (EDM) of siliconised or reaction-bonded silicon carbide (SiSiC) has been carried out. The selection of the above-mentioned conductive ceramic was made taking into account its wide range of applications in the industrial field: high-temperature gas turbines, bearings, seals and lining of

C. J. Luis; I. Puertas; G. Villa

2005-01-01

153

Parallel astronomical data processing with Python: Recipes for multicore machines  

NASA Astrophysics Data System (ADS)

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.

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

2013-08-01

154

In-process EDM truing to generate complex contours on metal-bond, superabrasive grinding wheels for precision grinding structural ceramics  

SciTech Connect

The demand and use of precision grinding of structural ceramics continue to increase as the worldwide advanced ceramic industry surpasses $20 billion is sales. Included in this industry are engineering structural ceramics, electronic ceramics, bioceramics and others. These materials are used in applications such as engine components, casting and extrusion dies, bearings, medical implants, nozzles, thermal insulators, and more. Along with the variety of ceramic applications comes a broad range of precision requirements, which in turn leads to various required processes to accommodate a spectrum of specifications. A process for grinding ceramic components to micrometer tolerances was employed and further developed at Lawrence Livermore National Laboratory for two separate grinding projects.

Piscotty, M.A.; Davis, P.J.; Saito, T.T.; Blaedel, K.L.; Griffith, L.

1997-08-01

155

A high-efficiency approach for fabricating mass micro holes by batch micro EDM  

NASA Astrophysics Data System (ADS)

This work is a follow-up study based on previous research. The study presents a novel approach for effective production of mass micro holes. Initially, a set of micro w-EDM mechanisms is designed and mounted on the developed precise tabletop CNC machine tool to fabricate the micro electrode array. The tension of the micro wire is precisely controlled by a magnetic force. Furthermore, micro vibrations of the wire during discharging are effectively suppressed by the developed vibration suppression system. To fabricate the mass micro holes, a microstructure array with a high-aspect ratio of 10 × 10 micro squared electrodes, width and height of 21 µm and 700 µm, respectively, for each electrode and 24 µm spacing between two electrodes is fabricated first by using the proposed 'reverse w-EDM' machining strategy. The electrodes array is directly utilized to drill the mass micro holes by bath micro EDM on the same machine. An array of 900 through-holes of the same size is successfully fabricated via the modified peck-drilling method on a 30 µm thick stainless-steel plate. A tip at the free end of the micro electrode is designed and fabricated as a circular-pyramid shape. Experimental results verified that the spiky end form eliminates debris adhering to the edges of the micro holes. Analytical results demonstrate satisfactory hole geometric accuracy, dimensional accuracy and surface roughness. Furthermore, mass micro holes can be fabricated efficiently using the proposed technique.

Chen, Shun-Tong

2007-10-01

156

Landers, Ulsoy, and Furness 1 Process Monitoring and Control of Machining Operations  

E-print Network

Landers, Ulsoy, and Furness 1 Process Monitoring and Control of Machining Operations Robert G . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 #12;Landers, Ulsoy, and Furness 2 1 INTRODUCTION Machining operations (e.g., drilling, milling phenomena naturally occur in machining operations which are detrimental to this objective. In this chapter

Landers, Robert G.

157

An Integrated Process Planning System for Machining and Inspection  

E-print Network

, and measurement operation information. A mechanism to link tolerance requirements and machining feature-between machining operations. Measurement of each critical tolerance is also planned by the developed system proper adjustments to the immediate subsequent machining operation(s). A software prototype was developed

Boyer, Edmond

158

MACHINE LEARNING IN REMOTE SENSING DATA PROCESSING Gustavo Camps-Valls  

E-print Network

and development in both directions. #12;2. TRADITIONAL MACHINE LEARNING FOR REMOTE SENSING In this section, weMACHINE LEARNING IN REMOTE SENSING DATA PROCESSING Gustavo Camps-Valls Image Processing Laboratory gustavo.camps@uv.es, http://www.uv.es/gcamps ABSTRACT Remote sensing data processing deals with real

Camps-Valls, Gustavo

159

Optimization analysis on the economy of the electro-discharge machining process using electronic pulse generator  

Microsoft Academic Search

Research is yet to be clone on the direct economy of the electro-discharge machining process which is a vital criterion for the users of the machine. In this paper an expression for contribution rate, as a function of process variables, which is a direct indicator to measure the economic objectives of the process for a production system is derived and

S. K. MUKHERJEE; M. N. PAL

1981-01-01

160

Intelligent Signal Processing Group, IMM, DTU / Jan Larsen 1 Search for sounds a machine learning approach  

E-print Network

Intelligent Signal Processing Group, IMM, DTU / Jan Larsen 1 Search for sounds ­ a machine learning Processing Group, IMM, DTU / Jan Larsen 2 Search for sounds ­ a machine learning approach The digital music will play a key role in future systems #12;Intelligent Signal Processing Group, IMM, DTU / Jan Larsen 3

161

A review of machining monitoring systems based on artificial intelligence process models  

Microsoft Academic Search

Many machining monitoring systems based on artificial intelligence (AI) process models have been successfully developed in\\u000a the past for optimising, predicting or controlling machining processes. In general, these monitoring systems present important\\u000a differences among them, and there are no clear guidelines for their implementation. In order to present a generic view of\\u000a machining monitoring systems and facilitate their implementation, this

Jose Vicente Abellan-Nebot; Fernando Romero Subirón

2010-01-01

162

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. ...

163

Cycle Time Reduction for Optimization Of Injection Molding Machine Parameters for Process Improvement  

Microsoft Academic Search

Injection molding is a worldwide business that companies around the world use as a predominant method in manufacturing. Optimizing the parameters of the injection molding machine is critical to improve manufacturing processes. This research focuses on the optimization of injection molding machine parameters using one material. Suggestions for process improvements are made based on the results of a designed experiment.

James Henderson; Aaron K. Ball; James Z. Zhang

164

Human DNA repair process recorded in action Published on Machines Like Us (http://  

E-print Network

Human DNA repair process recorded in action Published on Machines Like Us (http:// machineslikeus." University of California, Davis [1] Biology © Copyright MachinesLikeUs.com Source URL: http://machineslikeus.com/news/human-dna.com) Home > View content Human DNA repair process recorded in action By NLN Created 01/29/2009 - 15:35 A key

Kowalczykowski, Stephen C.

165

An improved mixed integer linear formulation and lower bounds for minimizing makespan on a flow shop with batch processing machines  

Microsoft Academic Search

This paper considers a flow shop scheduling problem with batch processing machines. Each batch processing machine has a limited\\u000a capacity and can process a group of jobs, each of them having a different known capacity requirement, simultaneously. Job\\u000a processing time on each machine is known and arbitrary. The processing time of a batch on each machine is the longest processing

Ali Husseinzadeh Kashan; Behrooz Karimi

2009-01-01

166

Scheduling Jobs with Variable Job Processing Times on Unrelated Parallel Machines  

PubMed Central

m unrelated parallel machines scheduling problems with variable job processing times are considered, where the processing time of a job is a function of its position in a sequence, its starting time, and its resource allocation. The objective is to determine the optimal resource allocation and the optimal schedule to minimize a total cost function that dependents on the total completion (waiting) time, the total machine load, the total absolute differences in completion (waiting) times on all machines, and total resource cost. If the number of machines is a given constant number, we propose a polynomial time algorithm to solve the problem. PMID:24982933

Zhang, Guang-Qian; Wang, Jian-Jun; Liu, Ya-Jing

2014-01-01

167

Processing and Damping Properties of Sputtered NiTi Thin Films for Tools in Machining Processes  

Microsoft Academic Search

Nowadays, many manufacturing processes require the machining of complex forms with a high aspect ratio or cavities. Tools\\u000a with a long overhang length are a common method to meet these requirements. Typical examples for this are boring bars for\\u000a bore-turning and the milling with very long cutters. These tools tend to vibrate strongly due to their slender shape. The\\u000a stress-induced

F. Kahleyss; R. Lima de Miranda; T. Surmann; C. Zamponi; C. Machai; D. Biermann; E. Quandt

2011-01-01

168

Flotation machine and process for removing impurities from coals  

DOEpatents

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.

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

1997-02-11

169

Flotation machine and process for removing impurities from coals  

DOEpatents

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.

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

1995-12-05

170

Flotation machine and process for removing impurities from coals  

DOEpatents

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.

Szymocha, Kazimierz (Edmonton, CA); Ignasiak, Boleslaw (Edmonton, CA); Pawlak, Wanda (Edmonton, CA); Kulik, Conrad (Newark, CA); Lebowitz, Howard E. (Mountain View, CA)

1995-01-01

171

Flotation machine and process for removing impurities from coals  

DOEpatents

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.

Szymocha, Kazimierz (Edmonton, CA); Ignasiak, Boleslaw (Edmonton, CA); Pawlak, Wanda (Edmonton, CA); Kulik, Conrad (Newark, CA); Lebowitz, Howard E. (Mountain View, CA)

1997-01-01

172

A MONTE CARLO SEQUENTIAL ESTIMATION OF POINT PROCESS OPTIMUM FILTERING FOR BRAIN MACHINE INTERFACES  

E-print Network

1 A MONTE CARLO SEQUENTIAL ESTIMATION OF POINT PROCESS OPTIMUM FILTERING FOR BRAIN MACHINE Monte Carlo Sequential Estimation for Point Processes.................................................29 Simulation of Monte Carlo Sequential Estimation on Neural Spike Train Decoding............32 Interpretation

Slatton, Clint

173

Preset Electrodes for Electrical-Discharge Machining  

NASA Technical Reports Server (NTRS)

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.

Coker, Bill E.

1987-01-01

174

Search for electron EDM with laser cooled radioactive atom  

NASA Astrophysics Data System (ADS)

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.

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

175

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

NASA Astrophysics Data System (ADS)

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.

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

176

Analysis and prediction of dimensions and cost of laser micro-machining internal channel fabrication process  

NASA Astrophysics Data System (ADS)

This paper presents the utilisation of Response Surface Methodology (RSM) as the prediction tool for the laser micro-machining process. Laser internal microchannels machined using pulsed Nd:YVO4 laser in polycarbonate were investigated. The experiments were carried out according to 33 factorial Design of Experiment (DoE). In this work the three input process set as control parameters were laser power, P; pulse repetition frequency, PRF; and sample translation speed, U. Measured responses were the channel width and the micro-machining operating cost per metre of produced microchannels. The responses were sufficiently predicted within the set micro-machining parameters limits. Two factorial interaction (2FI) and quadratic polynomial regression equations for both responses were constructed. It is proposed that the developed prediction equations can be used to find locally optimal micro-machining process parameters under experimental and operational conditions.

Shadi, K.; Brabazon, D.

2010-06-01

177

Sensorless control of induction machines with different designs — Impact on signal processing  

Microsoft Academic Search

This paper addresses the sensorless control scheme of induction machines using transient voltage excitation at zero and low frequencies. The method is based on saliency detection through the use of pulse excitation and the evaluation of the response of the machine line currents changes. Different signal processing structures are necessary for the rotor position estimation. The estimation algorithm of the

T. M. Wolbank; M. K. Metwally

2009-01-01

178

Machine tractable dictionaries as tools and resources for natural language processing  

Microsoft Academic Search

This paper discusses three different but related large-scale computational methods for the transformation of machine readable dictionaries (MRDs) into machine tractable dictionaries, i.e., MRDs converted into a format usable for natural language processing tasks. The MRD used is .

Yorick Wilks; Dan Fass; Cheng-ming Guo; James E. Mcdonald; Tony Plate; Brian M. Slator

1988-01-01

179

Process Parameters Optimization for Energy Saving in Paper Machine Dryer Section  

Microsoft Academic Search

Due to high energy consumption in the Chinese paper industry, this study considers higher-energy efficiency for the multicylinder dryer section of paper machines. A common situation in the Chinese paper industry is that energy is consumed in extensive mode. In order to improve the energy efficiency of the paper machine dryer section, deeper analysis and optimization of process parameters are

Yugang Li; Huanbin Liu; Jigeng Li; Jinsong Tao

2011-01-01

180

The self-excitation process in electrical rotating machines operating in pulsed power regime  

Microsoft Academic Search

The self-excitation process in pulsed air-core rotating generators is fundamental in assuring record values of power density and compactness. This paper analyzes the conditions for the self-excitation process in pulsed electrical machines used as power supplies for electromagnetic launchers, using the analogy and methods of the positive-feedback in control systems. In the classical “ferromagnetic” electrical machines in the self-excitation process,

M. D. Driga; S. B. Pratap; A. W. Walls; J. R. Kitzmiller

2001-01-01

181

Processing and Damping Properties of Sputtered NiTi Thin Films for Tools in Machining Processes  

NASA Astrophysics Data System (ADS)

Nowadays, many manufacturing processes require the machining of complex forms with a high aspect ratio or cavities. Tools with a long overhang length are a common method to meet these requirements. Typical examples for this are boring bars for bore-turning and the milling with very long cutters. These tools tend to vibrate strongly due to their slender shape. The stress-induced transformation of austenite to martensite and the distinctive hysteresis loop allow the NiTi shape memory alloys (SMA) to absorb vibration energy. This article describes the innovative approach to dampen process vibrations by coating the tool shafts of cutting tools with long overhang with NiTi thin films. It explores how these thin films can be applied on polished tungsten carbide shafts and how their modal parameters are modified by these coatings. In a further step, this knowledge is used to calculate stability charts of corresponding machining processes. The study reported in this article identified the stabilizing effects of coatings with a thickness of 2-4 ?m on milling processes. The minimum stability limit was increased by up to 200%.

Kahleyss, F.; de Miranda, R. Lima; Surmann, T.; Zamponi, C.; Machai, C.; Biermann, D.; Quandt, E.

2011-07-01

182

Neuro-fuzzy and neural network-based prediction of various responses in electrical discharge machining of AISI D2 steel  

Microsoft Academic Search

In the present research, two neuro-fuzzy models and a neural network model are presented for predictions of material removal\\u000a rate (MRR), tool wear rate (TWR), and radial overcut (G) in die sinking electrical discharge machining (EDM) process for American Iron and Steel Institute D2 tool steel with copper\\u000a electrode. The discharge current (I\\u000a p), pulse duration (T\\u000a on), duty cycle

Mohan Kumar Pradhan; Chandan Kumar Biswas

2010-01-01

183

An Open Architecture Real-Time Controller for Machining Processes  

Microsoft Academic Search

This paper presents an open architecturecontroller (OAC) for advanced machining anddescribes the OAC testbed at the Universityof Michigan. Because our OAC is designed forfully open systems, it does not depend on specifichardware or software components. Thisopenness includes software resuability whichenables integration of a wide range of monitoringand control features. Besides openness,our OAC system provides guaranteedreal-time operation, an important requirementfor advanced...

Galip Ulsoy; Jaehyun Park; Kang G. Shin; Yansong Shan; Yoram Koren; Zbigniew J. Pasek

1995-01-01

184

Parallel processing: a smart compiler and a dumb machine  

Microsoft Academic Search

Multiprocessors and vector machines, the only successful parallel architectures, have coarse-grained parallelism that is hard for compilers to take advantage of. We've developed a new fine-grained parallel architecture and a compiler that together offer order-of-magnitude speedups for ordinary scientific code.

Joseph A. Fisher; John R. Ellis; John C. Ruttenberg; Alexandru Nicolau

1984-01-01

185

1nEDM collaboration A. Serebrov, PSI Report 2002  

E-print Network

1nEDM collaboration A. Serebrov, PSI Report 2002 A new precision measurement of the neutron electric dipole moment (EDM) PSI, February 2003 E. Aleksandrov9 , M. Balabas9 , G. Ban4 , G. Bison8 , K Corpusculaire, Caen, France 5 PNPI, St. Petersburg Nuclear Physics Institute, Gatchina, Russia 6 PSI, Paul

Titov, Anatoly

186

Using multiple FPGA architectures for real-time processing of low-level machine vision functions  

Microsoft Academic Search

In this paper, we investigate the use of multiple field programmable gate array (FPGA) architectures for real-time machine vision processing. The use of FPGAs for low level processing represents an excellent tradeoff between software and special purpose hardware implementations. A library of modules that implement common low-level machine vision operations is presented. These modules are designed with gate-level hardware components

Thomas H. Drayer; William E. King; Joeseph G. Tront; R. W. Conners; Philip A. Araman

1995-01-01

187

A transputer-based shuffle-shift machine for image processing and reconstruction  

Microsoft Academic Search

A message-passing multicomputer is presented, and its application to image processing and reconstruction is outlined. The multicomputer may be seen as a one-dimensional array of computing nodes with bidirectional shuffle and shift connections. The resulting shuffle-shift machine is well suited for tasks like image processing and image reconstruction. A sample shuffle-shift machine has been built using transputers. The hardware and

H. Schomberg

1990-01-01

188

Boundary Processing of HHT Using Support Vector Regression Machines  

Microsoft Academic Search

In order to better restrain the end effects in Hilbert-Huang Transform, support vector regression machines (SVRM), which have\\u000a the superiority in the time series prediction, are adopted to extend the data at the both ends. In the application of SVRM,\\u000a the parameters have a great influence on the performance of generalization. In this paper the influence of parameters is discussed,

Wu Wang; Xueyao Li; Rubo Zhang

2007-01-01

189

Power metallurgy tool electrodes for electrical discharge machining  

Microsoft Academic Search

Electrodes in electrical discharge machining (EDM) can be compared with cutting tools in conventional machining. Tool performance is one of the important factors that determine the quality of the machined component. Due to the ease of manufacturing and control over the properties of electrodes, the powder metallurgy (P\\/M) technique has an advantage over other methods of electrode fabrication. P\\/M electrodes

M. P. Samuel; P. K. Philip

1997-01-01

190

An Investigation of Machining Characteristics in Micro-scale Milling Process  

SciTech Connect

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.

Ku, Min-Su; Kang, Ik-Soo [School of Mechanical Engineering, Pusan National University, San 30, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Kim, Jeong-Suk [School of Mechanical Engineering / Engineering Research Center for Net Shape and Die Manufacturing, Pusan National University, San 30, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of)

2011-01-17

191

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

DOEpatents

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.

Jones, Raymond Joseph (Duanesburg, NY); Bojappa, Parvangada Ganapathy (Schenectady, NY); Kirkpatrick, Francis Lawrence (Galway, NY); Schotsch, Margaret Jones (Clifton Park, NY); Rajan, Rajiv (Guilderland, NY); Wei, Bin (Mechanicville, NY)

2002-01-01

192

Hardening effect on machined surface for precise hard cutting process with consideration of tool wear  

NASA Astrophysics Data System (ADS)

During hard cutting process there is severe thermodynamic coupling effect between cutting tool and workpiece, which causes quenching effect on finished surfaces under certain conditions. However, material phase transformation mechanism of heat treatment in cutting process is different from the one in traditional process, which leads to changes of the formation mechanism of damaged layer on machined workpiece surface. This paper researches on the generation mechanism of damaged layer on machined surface in the process of PCBN tool hard cutting hardened steel Cr12MoV. Rules of temperature change on machined surface and subsurface are got by means of finite element simulation. In phase transformation temperature experiments rapid transformation instrument is employed, and the effect of quenching under cutting conditions on generation of damaged layer is revealed. Based on that, the phase transformation points of temperature under cutting conditions are determined. By experiment, the effects of cutting speed and tool wear on white layer thickness in damaged layer are revealed. The temperature distribution law of third deformation zone is got by establishing the numerical prediction model, and thickness of white layer in damaged layer is predicted, taking the tool wear effect into consideration. The experimental results show that the model prediction is accurate, and the establishment of prediction model provides a reference for wise selection of parameters in precise hard cutting process. For the machining process with high demanding on surface integrity, the generation of damaged layer on machined surface can be controlled precisely by using the prediction model.

Yue, Caixu; Liu, Xianli; Ma, Jing; Liu, Zhaojing; Liu, Fei; Yang, Yongheng

2014-11-01

193

PLANS FOR A NEUTRON EDM EXPERIMENT AT SNS  

SciTech Connect

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.

ITO, TAKEYASU [Los Alamos National Laboratory

2007-01-31

194

Manipulation of Ultracold Radium Atoms for a Nuclear EDM Measurement  

NASA Astrophysics Data System (ADS)

We describe recent progress towards measurement of the nuclear electric dipole moment (EDM) of radium. Neutral ultracold radium is loaded from a magneto-optic trap into an optical dipole trap (ODT), which is mechanically translated to move the radium into the science region. Here the atoms are observed and transferred into a second ODT suitable for EDM measurements. Short and long term prospects for upcoming permanent EDM measurements are discussed. Research supported by DOE, Office of Nuclear Physics, under contract DE-AC02-06CH11357.

Dietrich, M. R.; Bailey, K.; Greene, J. P.; Holt, R. J.; Kalita, M.; Korsch, W.; Lu, Z.-T.; Mueller, P.; Parker, R. H.; Singh, J.; Sulai, I. A.; O'Connor, T. P.

2011-06-01

195

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

SciTech Connect

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.

Johnston, Derek

2008-06-16

196

Noun-Noun Compound Machine Translation: A Feasibility Study on Shallow Processing  

E-print Network

of the NN compound (i.e. use deep processing), or sim- ply use the source language word forms to carry outNoun-Noun Compound Machine Translation: A Feasibility Study on Shallow Processing Takaaki Tanaka% of words in the BNC are NN compounds. More- over, if we plot the relative token coverage of the most

Baldwin, Timothy

197

An integrated method of independent component analysis and support vector machines for industry distillation process monitoring  

Microsoft Academic Search

For the complex operation and multi-loop control in the industry distillation process, the diagnosis of the complex fault has become more and more difficult. An integrated method of independent component analysis (ICA) and support vector machines (SVM) is proposed to detect and diagnose industry distillation process faults. The ICA is used for feature extraction and data reduction from original features.

Cuimei Bo; Xu Qiao; Guangming Zhang; Yangjin Bai; Shi Zhang

2010-01-01

198

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

SciTech Connect

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.

Schubert, A. [Fraunhofer Institute for Machine Tools and Forming Technology IWU, Chemnitz, 09126 (Germany); Chair Micromanufacturing Technology, Chemnitz University of Technology, Chemnitz, 09107 (Germany); Edelmann, J.; Gross, S.; Meichsner, G.; Wolf, N.; Schneider, J. [Fraunhofer Institute for Machine Tools and Forming Technology IWU, Chemnitz, 09126 (Germany); Zeidler, H.; Hackert, M. [Chair Micromanufacturing Technology, Chemnitz University of Technology, Chemnitz, 09107 (Germany)

2011-01-17

199

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

NASA Technical Reports Server (NTRS)

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.

Friedrich, Craig R.; Warrington, Robert O.

1995-01-01

200

Progress towards an atomic EDM measurement of Ra-225  

NASA Astrophysics Data System (ADS)

We are searching for the permanent electric dipole moment (EDM) of the Radium-225 nucleus. A nonzero nuclear EDM is a signature of CP- and T-violating interactions within nuclei. Currently, the best experimental limits on these interactions are derived from EDM measurements of Mercury-199. The Ra-225 radioisotope (half-life of 15 days) is an attractive alternative because, due to its peculiar shape (nuclear octupole deformation), it is predicted to be a few hundred to a few thousand times more sensitive to these types of interactions than Hg-199. In our measurement scheme, Ra atoms are first laser cooled and trapped in a magneto-optical trap and then transferred to an optical dipole trap (ODT), both of which have already been demonstrated. The ODT is moved to a magnetically-shielded science chamber, and then the atoms are transferred to a perpendicular ODT in which the EDM will be measured. Transfer efficiencies between the two ODT's as high as 60% have been demonstrated. We will report on progress towards measurements of atomic properties necessary for the EDM search and the EDM search itself. Research supported by DOE, Office of Nuclear Physics, contract No. DE-AC02-06CH11357.

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

2012-03-01

201

The effect of WC grain size and cobalt content on properties and electrical discharge machining of WC-Co composites  

E-print Network

. The peculiar decrease in thermal and electrical conductivities wss due to porosity which was 1'ound to increase with cobalt content. A wire electrical discharge machine (EDM) with pulse type power supply was used and specimen surfaces were assessed.... There are two types of electrical discharge machines: the ram-type and wire EDM. The ram-type machine uses a die to I'abricate the workpiece shape. The die material ranges from brass, steel or even WC-Co composites'. The wire EDM uses a metallic wire to cut...

Tsai, Wei-Lung

1988-01-01

202

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

NASA Astrophysics Data System (ADS)

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-emission 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.

Blau, P. J.; Howe, J. Y.; Coffey, D. W.; Trejo, R. M.; Kenik, E. D.; Jolly, B. C.; Yang, N.

2012-08-01

203

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

SciTech Connect

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.

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

2012-01-01

204

On the performance enhancement of self-tuning adaptive control for time-varying machining processes  

Microsoft Academic Search

This paper investigates efficient approaches to improve the performance of a self-tuning adaptive control system for time-varying machining processes. The milling process is a typical time-varying system because of variations of the cutting conditions, e.g., the change of cutting depths and variation of the cutting materials. On the other hand, the milling processes are considered as typically non-minimum phases since

Y. H. Peng

2004-01-01

205

Processing and properties of ultra-high temperature ceramics for space applications  

Microsoft Academic Search

The processing and the properties of two ultra-high temperature ceramics (UHTCs) designed for the manufacturing of aerospace sharp-shaped hot-structures are presented, along with the results obtained in the electrical discharge machining (EDM) of these UHTCs into sharp hot-structure components.The powder mixtures in the (ZrB2–SiC)-based systems were brought to full density by hot-pressing. The hot-pressed bodies were characterized by fine and

F. Monteverde; A. Bellosi; Luigi Scatteia

2008-01-01

206

Scheduling precedence-constrained jobs with stochastic processing times on parallel machines  

Microsoft Academic Search

We consider parallel machine scheduling problems where the jobs are subject to precedence constraints, and the processing times of jobs are governed by independent probability distributions. The objective is to minimize the weighted sum of job completion times ?, w, C, in expectation, where w, ⪈ 0. Building upon an LP-relaxation from [3] and an idle time charging scheme from

Martin Skutella; Marc Uetz

2001-01-01

207

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

NASA Technical Reports Server (NTRS)

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.

Roberts, F. E., III

1995-01-01

208

The Recognition of Cucumber Disease Based on Image Processing and Support Vector Machine  

Microsoft Academic Search

A new method of recognizing cucumber leaf disease based on computer image processing and Support Vector Machine (SVM) is studied to improve recognition accuracy and efficiency. At first, vector median filter was applied to remove noise of the acquired color images of cucumber disease leaf. Then a method of statistic pattern recognition and mathematics morphology was introduced to segment images

Tian Youwen; Li Tianlai; Niu Yan

2008-01-01

209

Solar activity detection and prediction using image processing and machine learning techniques  

Microsoft Academic Search

The objective of the research in this dissertation is to develop the methods for automatic detection and prediction of solar activities, including prominence eruptions, emerging flux regions and solar flares. Image processing and machine learning techniques are applied in this study. These methods can be used for automatic observation of solar activities and prediction of space weather that may have

Gang Fu

2007-01-01

210

Process Control in Next-Generation Sewing Machines: A Project Overview  

Microsoft Academic Search

SYNOPSIS The sewing machine created in the XIX century has roughly remained unchanged in its basic technologies. Although a great range of mechanical and electronic technologies has boosted its development enormously, the process of sewing itself, however, although perfected in many aspects, has remained uncontrolled.Many of the phenomena occurring at high-speed sewing (up to 10000 stitches per minute) are still

Helder Carvalho; João L. Monteiro

211

Computer-based diagnostic monitoring to enhance the human-machine interface of complex processes  

Microsoft Academic Search

There is a growing interest in introducing an automated, on-line, diagnostic monitoring function into the human-machine interfaces (HMIs) or control rooms of complex process plants. The design of such a system should be properly integrated with other HMI systems in the control room, such as the alarms system or the Safety Parameter Display System (SPDS). This paper provides a conceptual

1992-01-01

212

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

DOEpatents

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.

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

1991-06-11

213

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

DOEpatents

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.

Copley, Stephen M. (Palos Verdes, CA); Tao, Hongyi (Covina, CA); Todd-Copley, Judith A. (Palos Verdes, CA)

1991-01-01

214

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

NASA Astrophysics Data System (ADS)

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.

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

2014-09-01

215

Multibody simulation of machine tools as mechatronic systems for optimization of motion dynamics in the design process  

Microsoft Academic Search

Increasing demands on the productivity of machine tools and their growing technological complexity call for improved methods in future product development processes. The paper explains the application of integrated CAx tools for setting up a virtual prototype that will permit evaluation and optimization of the entire machine tool's motion dynamics in early phases of the development process. Based on the

Gunther Reinhart; Martin Weissenberger

1999-01-01

216

Punching in industrial wood machining: an alternative production process to drilling  

Microsoft Academic Search

Drilling of wood is besides milling, sawing and grinding one of the most important production processes in industrial furniture\\u000a manufacturing. For the body assembly and the fixing of fittings, boreholes are essential. They have immediate effect on quality\\u000a and production costs. The process step drilling limits the output of stationary and throughfeed machines, because the workpieces\\u000a have to be stopped

J. Hesselbach; H.-W. Hoffmeister; T. Loohß

2007-01-01

217

3D finite element simulation of tunnel boring machine construction processes in deep water conveyance tunnel  

Microsoft Academic Search

Applying stiffness migration method, a 3D finite element mechanical model is established to simulate the excavation and advance\\u000a processes. By using 3D nonlinear finite element method, the tunnel boring machine (TBM) excavation process is dynamically\\u000a simulated to analyze the stress and strain field status of surrounding rock and segment. The maximum tensile stress of segment\\u000a ring caused by tunnel construction

Denghua Zhong; Dawei Tong

2009-01-01

218

Monocular depth perception using image processing and machine learning  

NASA Astrophysics Data System (ADS)

This paper primarily exploits some of the more obscure, but inherent properties of camera and image to propose a simpler and more efficient way of perceiving depth. The proposed method involves the use of a single stationary camera at an unknown perspective and an unknown height to determine depth of an object on unknown terrain. In achieving so a direct correlation between a pixel in an image and the corresponding location in real space has to be formulated. First, a calibration step is undertaken whereby the equation of the plane visible in the field of view is calculated along with the relative distance between camera and plane by using a set of derived spatial geometrical relations coupled with a few intrinsic properties of the system. The depth of an unknown object is then perceived by first extracting the object under observation using a series of image processing steps followed by exploiting the aforementioned mapping of pixel and real space coordinate. The performance of the algorithm is greatly enhanced by the introduction of reinforced learning making the system independent of hardware and environment. Furthermore the depth calculation function is modified with a supervised learning algorithm giving consistent improvement in results. Thus, the system uses the experience in past and optimizes the current run successively. Using the above procedure a series of experiments and trials are carried out to prove the concept and its efficacy.

Hombali, Apoorv; Gorde, Vaibhav; Deshpande, Abhishek

2011-10-01

219

Application of machine learning and expert systems to Statistical Process Control (SPC) chart interpretation  

NASA Technical Reports Server (NTRS)

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.

Shewhart, Mark

1991-01-01

220

Progress toward an EDM measurement in Ra-225  

NASA Astrophysics Data System (ADS)

We are developing an EDM search based on laser-cooled and trapped Ra-225 (half-life = 15 d) atoms. Due to octupole deformation of the nucleus, Ra-225 is predicted to be 2-3 orders of magnitude more sensitive to T-violating interactions than Hg-199, which currently sets the most stringent limits in the nuclear sector. In preparation of an EDM measurement, we have trapped radium atoms first in a MOT and then transferred them to a far-off-resonant optical dipole trap. We will report progress towards the EDM search and the measurements of relevant atomic properties. This work is supported by DOE, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357.

Sulai, I. A.; Trimble, W. L.; Parker, R. H.; Bailey, K.; Greene, J. P.; Holt, R. J.; Korsch, W.; Lu, Z. T.; Mueller, P.; O'Connor, T. P.; Singh, J.

2010-03-01

221

Modeling of spark erosion rate in microwire-EDM  

Microsoft Academic Search

Micro-wire electro-discharge machining (WEDM) has been identified as a micromachining process for the fabrication of components\\u000a of size down to the micrometer level. This process is derived from WEDM, and the principle of both the process is similar,\\u000a yet due to significant scaling down of the micro-WEDM process, lots of modifications in the circuit design, wire diameter,\\u000a stresses developed, and

Saradindu Das; Suhas S. Joshi

2010-01-01

222

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

PubMed Central

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

Salehi, Mojtaba

2010-01-01

223

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

PubMed

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

Salehi, Mojtaba; Bahreininejad, Ardeshir

2011-08-01

224

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

NASA Astrophysics Data System (ADS)

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.

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

2012-06-01

225

Improvement of fatigue life of electrical discharge machined AISI D2 tool steel by TiN coating  

Microsoft Academic Search

This work presents the effects of titanium nitride (TiN) coating by physical vapor deposition (PVD) on the fatigue life of AISI D2 tool steel, which was electrical discharge machined (EDM) at various machining parameters, such as pulse current and pulse-on duration. Surface hardness, surface roughness, residual stress and fatigue strength were measured. Experimental results indicate that EDM treatment has a

Y. H. Guu; H. Hocheng

2001-01-01

226

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

NASA Astrophysics Data System (ADS)

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.

Ilyas, Ismet P.

2013-06-01

227

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

NASA Astrophysics Data System (ADS)

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.

Sharma, S.

2013-10-01

228

Rescheduling frequency in an FMS with uncertain processing times and unreliable machines  

Microsoft Academic Search

This paper studies the scheduling\\/rescheduling problem in a multi-resource FMS environment. Several reactive scheduling policies are proposed to address the effects of machine breakdowns and processing time variations. Both off-line and on-line scheduling methods are tested under a variety of experimental conditions. The performance of the system is measured for mean tardiness and makespan criteria. The relationships between scheduling frequency

Suleyman Karabuk

1999-01-01

229

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

NASA Astrophysics Data System (ADS)

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.

Trochimczuk, R.; Ku?mierowski, T.

2014-11-01

230

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

Microsoft Academic Search

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

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

2011-01-01

231

Non-stationary Policy Learning in 2-player Zero Sum Games Content Areas: machine learning, Markov decision processes, reinforcement learning  

E-print Network

Non-stationary Policy Learning in 2-player Zero Sum Games Content Areas: machine learning, Markov over the space of stochastic actions. Many previous machine learning approaches apply to single agent decision processes, reinforcement learning Abstract A key challenge in multiagent environments is the con

He, Sheng

232

The nEDM experiment at the SNS  

NASA Astrophysics Data System (ADS)

The nEDM collaboration proposes to measure the neutron electric dipole moment at the Spallation Neutron Source (Oak Ridge National Laboratory). The nEDM is a clear signature of CP violation. According to the Standard Model the nEDM is very small (˜10-31 e cm), but many theories predict much higher values. In the proposed experiment polarized cold neutrons from the SNS would be trapped in liquid helium at a temperature of about 400 mK. The neutron spin would precess in a very uniform magnetic field ( H ˜ 30 mG), and the experiment would measure the change in the precession frequency when a very strong electric field ( E ˜ 50 kV/cm) is applied. Polarized 3He atoms serve as a co-magnetometer. The goal of the experiment is to measure the nEDM with an accuracy of ˜9 × 10-28 e cm, which is more than an order of magnitude better than existing results.

Tsentalovich, E. P.

2014-01-01

233

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

NASA Astrophysics Data System (ADS)

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.

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

2012-09-01

234

Abrasive micro-blasting to improve surface integrity of electrical discharge machined WC–Co composite  

Microsoft Academic Search

This study investigates the improvement of surface integrity of wire electrical discharge machined (EDM) WC–Co composite by abrasive micro-blasting. The thermally damaged recast layer generated by EDM has craters, cracks, and bubbles, which deteriorate the surface mechanical properties. The micro-blasting, using 6–12 and 4–20?m size SiC abrasive, enables the removal of the recast layer and is suitable for micro mechanical

Jun Qu; Albert J. Shih; Ronald O. Scattergood; Jie Luo

2005-01-01

235

Electrical discharge machining of B 4C–TiB 2 composites  

Microsoft Academic Search

The interrelationships between the microstructure and electrical discharge machining (EDM) behaviour of B4C–TiB2 composites with respectively 30, 40 and 60vol.% TiB2 are investigated. Special attention was given to the influence of the grain size on the EDM behaviour by producing composites with an ultrafine TiB2 phase using in situ synthesis during PECS. The experimental work revealed that 40vol.% of TiB2

Olivier Malek; Jef Vleugels; Kim Vanmeensel; Shuigen Huang; Junhu Liu; Sven Van den Berghe; Amit Datye; Kuang-Hsi Wu; Bert Lauwers

2011-01-01

236

Wire electric discharge machining induced titanium hydride in Ti–46Al–2Cr alloy  

Microsoft Academic Search

Wire electric discharge machining (Wire-EDM) induced a new phase in Ti–46Al–2Cr (in at.%) intermetallic alloy has been identified by using X-ray diffraction technique. The new phase is found to be neither TiO2 nor Al2O3, but well consistent with fcc structure titanium hydride with the lattice parameter of 4.49–4.50 Å. The new phase exists in the wire-EDM cut alloy surface layer

G. W. Qin; K. Oikawa; G. D. W. Smith; S. M. Hao

2003-01-01

237

Cooperative optimization of reconfigurable machine tool configurations and production process plan  

NASA Astrophysics Data System (ADS)

The production process plan design and configurations of reconfigurable machine tool (RMT) interact with each other. Reasonable process plans with suitable configurations of RMT help to improve product quality and reduce production cost. Therefore, a cooperative strategy is needed to concurrently solve the above issue. In this paper, the cooperative optimization model for RMT configurations and production process plan is presented. Its objectives take into account both impacts of process and configuration. Moreover, a novel genetic algorithm is also developed to provide optimal or near-optimal solutions: firstly, its chromosome is redesigned which is composed of three parts, operations, process plan and configurations of RMTs, respectively; secondly, its new selection, crossover and mutation operators are also developed to deal with the process constraints from operation processes (OP) graph, otherwise these operators could generate illegal solutions violating the limits; eventually the optimal configurations for RMT under optimal process plan design can be obtained. At last, a manufacturing line case is applied which is composed of three RMTs. It is shown from the case that the optimal process plan and configurations of RMT are concurrently obtained, and the production cost decreases 6.28% and nonmonetary performance increases 22%. The proposed method can figure out both RMT configurations and production process, improve production capacity, functions and equipment utilization for RMT.

Xie, Nan; Li, Aiping; Xue, Wei

2012-09-01

238

Metallurgical Analysis of Crack Initiation of Wire-Cut Electrical Discharge-Machined Spline Actuators Made of 17-4 PH Stainless Steel  

Microsoft Academic Search

Spline actuators made of investment cast 17-4 PH (precipitation hardening) stainless steel were found to contain micro-cracks.\\u000a The cracked actuators were subjected to optical and scanning electron microscopy and hardness testing, which revealed that\\u000a the failure occurred due to fatigue crack initiation and growth after electrical discharge machining (EDM). The rehardened\\u000a layer produced by the EDM remained after machining, and

Ahmad-Reza Etemadi; Bahram Fazel; Armin Emami

239

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

NASA Astrophysics Data System (ADS)

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.

Elkaseer, A.; Brousseau, E. B.

2014-04-01

240

Optical dipole trapping of radium atoms for EDM search  

NASA Astrophysics Data System (ADS)

We are developing an EDM search based on laser-cooled and trapped Ra-225 (half-life = 15 d) atoms. Due to octupole deformation of the nucleus, Ra-225 is predicted to be 2-3 orders of magnitude more sensitive to T-violating interactions than Hg-199, which currently sets the most stringent limits in the nuclear sector. Recently, we have succeeded in transferring Ra-226 atoms from a MOT into an optical dipole trap formed by a fiber laser beam at 1550 nm. For the EDM measurement, the cold atoms will be moved into the neighboring vacuum chamber inside magnetic shields where a pair of electrodes apply a 10 kV cm-1electric field. This work is supported by DOE, Office of Nuclear Physics under contract No. DE-AC02-06CH11357.

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

2010-03-01

241

Near net shape processing of RE Ba Cu O bulk superconductor by machining binder-added precursors  

NASA Astrophysics Data System (ADS)

Several practical applications of melt-textured bulk superconductors require the complex-shaped products such as curved, ring-shaped, and drilled blocks rather than simple shaped pellets. In general, complex-shaped bulk products are prepared by machining melt-grown massive blocks. However, melt-textured bulks are often damaged when they are mechanically machined. With the aim of reducing such damages, we have investigated the preparation of the complex-shaped bulk superconductors by previously machining the precursors compacted with organic binders. The mixed powders of Y123 and Y211 were pressed into pellets, for which the organic binder was added are machined into complex-shaped bodies. After removal of the organic components, melt-processing was performed in air, which led to a reproducible fabrication of complex-shaped bulk products. The superconducting properties were not degraded with this process.

Fujikura, M.; Nariki, S.; Sakai, N.; Hirabayashi, I.; Murakami, M.

2005-10-01

242

Automated process planning method to machine A B-Spline free-form feature on a mill–turn center  

Microsoft Academic Search

In this paper, we present a methodology for automating the process planning and NC code generation for a widely encountered class of free-form features that can be machined on a 3-axis mill–turn center. The free-form feature family that is considered is that of extruded protrusions whose cross-section is a closed, periodic B-Spline curve. In this methodology, for machining a part

Nikhil Date; Prakash Krishnaswami; V. V. Satish K. Motipalli

2009-01-01

243

Image processing as a tool to improve machine performance and process control  

Microsoft Academic Search

Image processing has been used as a tool to determine the trash content in cotton webs. The experiments showed that in particular seed coat particles are difficult to separate from the cotton during cleaning processes whereas neps, leaf and wooden fragments can easily be removed. A correlation between the number of seed coat particles and USTER-imperfections in the yarn has

D. Veit; I. Hormes; J. Bergmann; B. Wulfhorst

1996-01-01

244

Page 296 Courses: Education: Multiple Subject (EDMS) Sonoma State University 2011-2012 Catalog Education: Multiple Subject (EDMS)  

E-print Network

and written language, literature study and composing strategies. Grade only. edMS 464 teAChinG reAdinG And lAnGuAGe they confront in our educational system. They will analyze what it means to be a teacher today in our elementaryAChinG SeCOnd lAnGuAGe leArnerS (3) This course examines first and second language acquisition and major

Ravikumar, B.

245

Page 298 Courses: Education: Multiple Subject (EDMS) Sonoma State University 2010-2011 Catalog Education: Multiple Subject (EDMS)  

E-print Network

and written language, literature study and composing strategies. Grade only. edMS 464 teAChinG reAdinG And lAnGuAGe they confront in our educational system. They will analyze what it means to be a teacher today in our elementaryAChinG SeCOnd lAnGuAGe leArnerS (3) This course examines first and second language acquisition and major

Ravikumar, B.

246

Tool Path Planning Generation For Finish Machining of Freeform Surfaces in the Cybercut Process Planning Pipeline  

E-print Network

for the finishing operation. Machining large surfaces withmachining op- eration. Tools of small diameter are used for the finishing operation.machining criterion of specified design- tolerance. Feed-forward Marching Most of the cutting operation

Wright, Paul K; Dornfeld, David; Sundararajan, V.; Misra, Debananda

2007-01-01

247

Process Modeling In Cold Forging Considering The Process-Tool-Machine Interactions  

NASA Astrophysics Data System (ADS)

In this paper, a methodic approach is presented for the determination and modeling of the axial deflection characteristic for the whole system of stroke-controlled press and tooling system. This is realized by a combination of experiment and FE simulation. The press characteristic is uniquely measured in experiment. The tooling system characteristic is determined in FE simulation to avoid experimental investigations on various tooling systems. The stiffnesses of press and tooling system are combined to a substitute stiffness that is integrated into the FE process simulation as a spring element. Non-linear initial effects of the press are modeled with a constant shift factor. The approach was applied to a full forward extrusion process on a press with C-frame. A comparison between experiments and results of the integrated FE simulation model showed a high accuracy of the FE model. The simulation model with integrated deflection characteristic represents the entire process behavior and can be used for the calculation of a mathematical process model based on variant simulations and response surfaces. In a subsequent optimization step, an adjusted process and tool design can be determined, that compensates the influence of the deflections on the workpiece dimensions leading to high workpiece accuracy. Using knowledge on the process behavior, the required number of variant simulations was reduced.

Kroiss, Thomas; Engel, Ulf; Merklein, Marion

2010-06-01

248

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

NASA Technical Reports Server (NTRS)

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.

Fiebrich, Rolf-Dieter

1987-01-01

249

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

NASA Astrophysics Data System (ADS)

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.

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

2005-11-01

250

Hybrid metaheuristics for solving a fuzzy single batch-processing machine scheduling problem.  

PubMed

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

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

2014-01-01

251

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

PubMed

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

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

2011-01-01

252

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

NASA Technical Reports Server (NTRS)

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.

Alsberg, H.; Nathan, R.

1975-01-01

253

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

PubMed Central

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

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

2014-01-01

254

Modeling of Electrical Discharge Machining Process Using Conventional Regression Analysis and Genetic Algorithms  

NASA Astrophysics Data System (ADS)

An attempt was made to model input-output relationships of an electrical discharge machining process based on the experimental data (collected according to a central composite design) using multiple regression analysis. Three input parameters, such as peak current, pulse-on-time and pulse-duty-factor, and two outputs, namely, material removal rate (MRR) and surface roughness (SR) had been considered for the said modeling. The value of regression coefficient was determined for each model. The performances of the developed models were tested with the help of some test cases collected through the real experiments and were found to be satisfactory. It had been posed as an optimization problem and solved using a genetic algorithm to determine the set(s) of optimal parameters for ensuring the maximum MRR and minimum SR. It was also formulated as a multi-objective optimization problem and a Pareto-optimal front of solutions had been obtained.

Maji, Kuntal; Pratihar, Dilip Kumar

2011-10-01

255

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

NASA Technical Reports Server (NTRS)

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.

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

1976-01-01

256

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

NASA Astrophysics Data System (ADS)

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.

Plank, Harald

2015-02-01

257

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

PubMed

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. PMID:25580777

Plank, Harald

2015-02-01

258

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

NASA Technical Reports Server (NTRS)

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.

Thomson, F.

1975-01-01

259

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

SciTech Connect

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.

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

1997-06-01

260

Solar activity detection and prediction using image processing and machine learning techniques  

NASA Astrophysics Data System (ADS)

The objective of the research in this dissertation is to develop the methods for automatic detection and prediction of solar activities, including prominence eruptions, emerging flux regions and solar flares. Image processing and machine learning techniques are applied in this study. These methods can be used for automatic observation of solar activities and prediction of space weather that may have great influence on the near earth environment. The research presented in this dissertation covers the following topics: (i) automatic detection of prominence eruptions (PEs), (ii) automatic detection of emerging flux regions (EFRs), and (iii) automatic prediction of solar flares. In detection of prominence eruptions, an automated method is developed by combining image processing and pattern recognition techniques. Consecutive Ha solar images are used as the input. The image processing techniques, including image transformation, segmentation and morphological operations are used to extract the limb objects and measure the associated properties. The pattern recognition techniques, such as Support Vector Machine (SVM), are applied to classify all the objects and generate a list of identified the PEs as the output. In detection of emerging flux regions, an automatic detection method is developed by using multi-scale circular harmonic filters. Kalman filter and SVM. The method takes a sequence of consecutive Michelson Doppler Imager (MDI) magnetograms as the input. The multi-scale circular harmonic filters are applied to detect bipolar regions from the solar disk surface and these regions are traced by Kalman filter until their disappearance. Finally, a SVM classifier is applied to distinguish EFRs from the other regions based on statistical properties. In solar flare prediction, it is modeled as a conditional density estimation (CDE) problem. A novel method is proposed to solve the CDE problem using kernel-based nonlinear regression and moment-based density function reconstruction techniques. This method involves two main steps. In the first step, kernel-based nonlinear regression techniques are applied to predict the conditional moments of the target variable, such as flare peak intensity or flare index. In the second step, the condition density function is reconstructed based on the estimated moments. The method is compared with the traditional double-kernel density estimator, and the experimental results show that it yields the comparable performance of the double-kernel density estimator. The most important merit of this new method is that it can handle high dimensional data effectively, while the double-kernel density estimator has confined to the bivariate case due to the difficulty of determining optimal bandwidths. The method can be used to predict the conditional density function of either flare peak intensity or flare index, which shows that our method is of practical significance in automated flare forecasting.

Fu, Gang

2007-07-01

261

Application of system engineering processes to analyze and predict engine cooling fan system noise for off-highway machines  

Microsoft Academic Search

System Engineering processes were applied to create a Cooling Fan System Noise Analysis Tool for a back-hoe loader machine. The Cooling Fan System Noise Analysis Tool combined elements of aeroacoustic theory, Fan Law, sound power measurements and particle image velocimetry into a single computer analysis tool. The cooling fan system consisted of a cooling fan, multiple radiators in front of

Christopher P. Masini; J. Adin Mann

2005-01-01

262

The effects of powder suspended dielectrics on the thermal influenced zone by electrodischarge machining with small discharge energies  

Microsoft Academic Search

EDM is used to machine every electrically conductive material by removing material through electrical discharges in a dielectric fluid. During machining the heat intensity from the spark melts a part of the workpiece. This liquid phase of the material resolidifies rapidly and builds the recast layer. A lot of work has been done before to explain the physical principles governing

F. Klocke; D. Lung; G. Antonoglou; D. Thomaidis

2004-01-01

263

A study of abrasive water jet machining process on glass\\/epoxy composite laminate  

Microsoft Academic Search

Surface roughness (Ra) and kerf taper ratio (TR) characteristics of an abrasive water jet machined surfaces of glass\\/epoxy composite laminate were studied. Taguchi's design of experiments and analysis of variance were used to determine the effect of machining parameters on Ra and TR. Hydraulic pressure and type of abrasive materials were considered as the most significant control factor in influencing

M. A. Azmir; A. K. Ahsan

2009-01-01

264

Machines of life: catalogue, stochastic process modeling, probabilistic reverse engineering and the PIs- from Aristotle to Alberts  

E-print Network

Molecular machines consist of either a single protein or a macromolecular complex composed of protein and RNA molecules. Just like their macroscopic counterparts, each of these nano-machines has an engine that "transduces" input energy into an output form which is then utilized by its coupling to a transmission system for appropriate operations. The theory of heat engines, pioneered by Carnot, rests on the second law of equilibrium thermodynamics. However, the engines of molecular machines, operate under isothermal conditions far from thermodynamic equilibrium. Moreover, one of the possible mechanisms of energy transduction, popularized by Feynman and called Brownian ratchet, does not even have any macroscopic counterpart. But, {\\it molecular machine is not synonymous with Brownian ratchet}; a large number of molecular machines actually execute a noisy power stroke, rather than operating as Brownian ratchet. The man-machine analogy, a topic of intense philosophical debate in which many leading philosophers like Aristotle and Descartes participated, was extended to similar analogies at the cellular and subcellular levels after the invention of optical microscope. The idea of molecular machine, pioneered by Marcelo Malpighi, has been pursued vigorously in the last fifty years. It has become a well established topic of current interdisciplinary research as evident from the publication of a very influential paper by Alberts towards the end of the twentieth century. Here we give a non-technical overview of the strategies for (a) stochastic modeling of mechano-chemical kinetic processes, and (b) model selection based on statistical inference drawn from analysis of experimental data. It is written for non-experts and from a broad perspective, showing overlapping concepts from several different branches of physics and from other areas of science and technology.

Debashish Chowdhury

2012-03-14

265

Simple Machines  

NSDL National Science Digital Library

Through a five-lesson series with five activities, students are introduced to six simple machines—inclined plane, wedge, screw, lever, pulley, wheel-and-axle—as well as compound machines, which are combinations of two or more simple machines. Once students understand about work (work = force x distance), they become familiar with the machines' mechanical advantages, and see how they make work easier. Through an introduction to compound machines, students begin to think critically about machine inventions and their pervasive roles in our lives. After learning about Rube Goldberg contraptions—absurd inventions that complete simple tasks in complicated ways—they evaluate the importance and usefulness of the many machines around them. Through the hands-on activities, students draw designs for contraptions that could move a circus elephant into a rail car, create a construction site ramp design by measuring different inclined planes and calculating the ideal vs. actual mechanical advantage of each, compare the theoretical and actual mechanical advantages of different pulley systems conceived to save a whale, build and test grape catapults made with popsicle sticks and rubber bands, and follow the steps of the engineering design process to design and build Rube Goldberg machines.

Integrated Teaching and Learning Program,

266

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)

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 µm 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.

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

2014-08-01

267

The Feasibility Analysis of Electrical-Discharge Machining of Carbon-Carbon Composites  

Microsoft Academic Search

The objective of this research is to investigate the feasibility of using Electrical-Discharge Machining (EDM) for carbon-carbon composite materials as well as the effects of major machining parameters. The material was machined by electrical-discharge sinker using copper electrode. The mechanism of material removal has been revealed by the morphology of debris. The material removal rate, the surface topography and the

H. Hocheng; Y. H. Guu; N. H. Tai

1998-01-01

268

On the Machining Dynamics of Turning and Micro-milling Processes  

E-print Network

Excessive vibrations continue to be a major hurdle in improving machining efficiency and achieving stable high speed cutting. To overcome detrimental vibrations, an enhanced understanding of the underlying nonlinear dynamics is required. Cutting...

Halfmann, Eric

2012-10-19

269

Permanent EDM measurement in Cs using nonlinear magneto-optic rotation  

E-print Network

We use the technique of chopped nonlinear magneto-optic rotation in a paraffin-coated Cs vapor cell to look for a permanent electric dipole moment (EDM) in the atom. The signature of the EDM is a shift in the Larmor precession frequency correlated with application of an electric field. Using a field of 2.6 kV/cm, we place an upper limit on the electron EDM of $ 7.7 \\times 10^{-22} $ e-cm. This limit can be improved by 5 to 6 orders-of-magnitude (and brought below the current best experimental limit) with simple improvements to the technique.

Ravi, Harish; Natarajan, Vasant

2015-01-01

270

The electron and neutron EDM from supersymmetric see-saw thresholds  

E-print Network

We consider the corrections that arise at one loop when integrating out heavy fields in supersymmetric models. We show that, in type-I see-saw models, complex A and B terms of the heavy right-handed neutrino give radiative contributions to the neutron EDM, as well as new dominant contributions to the electron EDM. Type-II and type-III see-saw also predict a pure gauge correction that makes complex the masses of the weak gauginos. All the see-saw models can predict observable EDM for the electron and for the neutron in a peculiar ratio.

Gian F. Giudice; Paride Paradisi; Alessandro Strumia

2010-03-11

271

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

NASA Technical Reports Server (NTRS)

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.

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

1975-01-01

272

High precision batch mode micro-electro-discharge machining of metal alloys using DRIE silicon as a cutting tool  

NASA Astrophysics Data System (ADS)

This paper reports recent advances in batch mode micro-electro-discharge machiningEDM) for high precision micromachining of metal alloys such as stainless steel. High-aspect-ratio silicon microstructures with fine feature sizes formed by deep reactive ion etching are used as cutting tools. To machine workpiece features with widths ?10 µm, a silicon dioxide coating is necessary to passivate the sidewalls of the silicon tools from spurious discharges. In the machined workpieces, a minimum feature size of ?7 µm and an aspect ratio up to 3.2 are demonstrated by the batch mode µEDM of stainless steel 304 and titanium (Grade 1) substrates. Machining rates up to ?5 µm min-1 in feature depth are achieved in batch mode micromachining of typical microfluidic structures, including arrays of channels and cavities of different sizes. The machined features are uniform across a die-scale area of 5 × 5 mm2. Other machining characteristics are also discussed.

Li, Tao; Bai, Qing; Gianchandani, Yogesh B.

2013-09-01

273

A novel laser micro\\/nano-machining system for FPD process  

Microsoft Academic Search

Laser machining technology has potential to be adopted as micro- and nano-fabrication equipments in the field of flat panel display (FPD) industry. The equipments repair short, open or protrusion defects by cutting and welding using high-power laser. The equipments should be able to carry large sized mother glass and have high productivity and accuracy. To meet the requirements, the equipment

Kihyun Kim; Young-Man Choi; Dea-Gab Gweon; Moon G. Lee

2008-01-01

274

Support vector machines for quality monitoring in a plastic injection molding process  

Microsoft Academic Search

Support vector machines (SVMs) are receiving increased attention in different application domains for which neural networks (NNs) have had a prominent role. However, in quality monitoring little attention has been given to this more recent development encompassing a technique with foundations in statistic learning theory. In this paper, we compare C-SVM and ?-SVM classifiers with radial basis function (RBF) NNs

Bernardete Ribeiro

2005-01-01

275

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

NASA Technical Reports Server (NTRS)

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.

Knuth, Kevin H.

2003-01-01

276

On the effect of electrodischarge machining parameters on the fatigue life of AISI D6 tool steel  

Microsoft Academic Search

The effects of current setting and pulse-on time on the fatigue lives of AISI D6 tool steel specimens produced using three-dimensional cavity machining are investigated. Optical and scanning electron microscopy, microprobe analysis and microhardness tests have been used to study the characteristics of the machined and fractured specimens. The results have confirmed the deteriorating effect of electrodischarge machining (EDM) on

O. A. Abu Zeid

1997-01-01

277

A New Limit on the Permanent Electric Dipole Moment (EDM) of ^199Hg  

NASA Astrophysics Data System (ADS)

A finite permanent electric dipole moment (EDM) of a particle or atom would violate time reversal symmetry (T), and would also imply violation of the combined charge conjugation and parity symmetry (CP) through the CPT theorem. EDMs are suppressed in the standard model of particle physics (SM), lying many orders of magnitude below current experimental sensitivity. It is generally accepted, however, that extra sources of CP violation are needed to account for baryogenesis and many theories beyond the SM, such as supersymmetry, naturally predict EDMs within experimental reach. To date, EDM searches have yielded null results. The most precise and significant limits have been set on the EDM of the neutronootnotetextC.A. Baker, et al., Phys. Rev. Lett. 97, 131801 (2006)., the electronootnotetextB.C. Regan, et al., Phys. Rev. Lett. 88, 071805 (2002)., and the ^ 199Hg atomootnotetextM.V. Romalis, et al., Phys. Rev. Lett. 86, 2505 (2001)., leading to tight constraints on sypersymmetric extensions of the SM. I will describe the results from a new experimental search for the EDM of ^199 Hg. We find d(^199Hg) = (0.49 ±1.29stat±0.76syst) x10-29 e cm, and interpret this as a new upper bound, d(^199Hg) < 3.1x10-29 e cm (95% C.L.)ootnotetextW.C. Griffith, et al., ArXiv:0901.2328v1.. This result improves our previous ^ 199Hg limit by a factor of 7 and offers a yet more exacting probe of possible new sources of CP violation. The experiment utilizes a stack of four spin-polarized Hg vapor cells in a common B-field. The middle two cells have oppositely directed E-fields, resulting in EDM-sensitive Larmor shifts of opposite sign; the outer two cells, enclosed by the high voltage (HV) electrodes and thus placed at E = 0, are free of EDM effects and instead allow cancelation of B- field gradient noise and checks for spurious HV-correlated B- field shifts. The dataset consists of 166 runs, with each run lasting roughly 24 hours and comprising several hundred E- field reversals. Measurements were performed for nine different vapor cells, four electrodes, two cell-containing vessels, and multiple vapor cell and electrode orientations. An unknown, HV- correlated, EDM-mimicking offset was added to the fitted values of the middle cell precession frequencies. This fixed blind offset masked the measured EDM and was revealed only after the data collection, data cuts, and error analysis were complete. In addition to experimental results, I will briefly outline the resulting new upper bounds on fundamental CP violating parameters.

Loftus, Thomas H.

2009-05-01

278

A structured approach to the automatic planning of machining operations for rotational parts based on computer integration of standard design and process data  

Microsoft Academic Search

The traditional procedure for developing a manufacturing process plan involves a number of interconnected steps beginning\\u000a with the initial design and culminating in the instructions for the machine that makes the part. When performed manually,\\u000a the procedure is very tedious, time consuming, and often, inconsistent. This paper presents an alternative method, called\\u000a the Automated Machining-Operations Process-Planning System (AMOPPS), to automatically

C.-H. Yeh; G. W. Fischer

1991-01-01

279

Electro Discharge Machining of Titanium Nitride-Aluminium Oxide Composite for Optimum Process Criterial Yield  

Microsoft Academic Search

Titanium nitride-aluminium oxide (TiN–Al2O3) is a new generation ceramic composite material having potential for many industrial applications as it possesses high resistance to thermal degradation, anti-wear and anti-abrasion properties. But conventional machining of such ceramic composite is difficult to perform for some of its peculiar properties like anisotropy, low thermal conductivity, and abrasive nature of the reinforcing phases. In the

D. Bhaduri; A. S. Kuar; S. Sarkar; S. K. Biswas; S. Mitra

2009-01-01

280

Toolbit Mounted Thin Film Zinc Oxide Sensors for Process Control in Lathe and Milling Machine Applications  

Microsoft Academic Search

Thin films (1.8 microns thick) of ZnO have been deposited on tungsten carbide tool inserts by rf diode sputtering. The goal is to use ZnO film as a sensor to monitor acoustic emission generated during cutting or t ool fracture. The sensor has detected resonances in the machine structure in the 100 Hz to 20 KHz range as well as

Brian Bischoff; S. Ramalingam; William P. Robbins

1987-01-01

281

A discrete-event simulation approach to predict power consumption in machining processes  

Microsoft Academic Search

Whereas in the past the sustainable use of resources and the reduction of waste have mainly been looked at from an ecological\\u000a point of view, resource efficiency recently becomes more and more an issue of cost saving as well. In manufacturing engineering\\u000a especially the reduction of power consumption of machine tools and production facilities is in the focus of industry,

Roland Larek; Ekkard Brinksmeier; Daniel Meyer; Thorsten Pawletta; Olaf Hagendorf

282

Recycle process for depleted-uranium machining chips by vacuum-induction remelt. Final report  

Microsoft Academic Search

The objective of the effort described in this report was to develop a method by which oxidized machining chips of depleted uranium, DU-3\\/4 titanium, generated in the production of large caliber penetrators, could be recycled as part of the charge in melting and casting of the alloy. The melting of this material was carried out by means of vacuum-induction techniques.

C. E. Latham-Brown; D. Vanderkooi

1987-01-01

283

Machine Vision  

NSDL National Science Digital Library

An overview of a generic image-based machine vision system is provided on this Web site (1). The tutorial describes the main components of such a system, how its accuracy is measured, and what scientific and industrial applications benefit from machine vision. A more technical perspective of machine vision technology is given in an online publication of the Automated Imaging Association (2). Monthly feature articles discuss breaking issues related to machine vision, and several technical papers can be downloaded, which are sorted into categories such as three dimensional imaging and nanotechnology. Researchers from the MIT's Artificial Intelligence Laboratory (3) are investigating how to enable a computer to interpret visual and audio signals from its human user. By using machine perception systems to track the user's gaze, for example, the computer could ascertain the focus of the user's attention, thereby facilitating interaction between the human and the computer. The project's homepage includes numerous research papers, as well as video demonstrations of some of its systems. Machine vision is also finding its way into vehicles. A March 2003 news article (4) highlights a field test in Michigan of a collision avoidance system that uses, among other things, machine vision to warn drivers that they are approaching a slower or stopped object too quickly. The 3D Computer Vision Group at Carnegie Mellon University (5) is involved in several projects, including three dimensional object recognition and humanoid robot vision. Many of the group's recent publications are available for download. NASA's Mars Exploration Rovers, the second of which was launched in July 2003, have vision systems that will let them safely navigate rough terrain. These systems are described in this conference paper (6), including specifics of the stereo vision algorithm and insights into future missions. A new implementation of machine vision comes from a former researcher from Cambridge University. His shape recognition system, which is detailed in this news article (7), is reportedly much more related to human visual processes than existing techniques. For additional developments related to this evolving technology, Machine Vision News (8) has information about worldwide research and new applications of machine vision systems.

Leske, Cavin.

284

Extreme Kicking Machine  

NSDL National Science Digital Library

In this design challenge activity follow up to "Kicking Machine", learners add a hands-free feature to their Kicking Machine. Learners modify their kicking machine to have it either release the pendulum or rubber band while standing three feet away or have it automatically feed balls into the kicking machine, one after another. They must figure out how to integrate the new feature into the existing structure and use the design process to make sure the modified kicking machine works properly. Educators can use this activity to demonstrate simple machines and kinetic/potential energy.

2012-08-20

285

Automatic Inspection During Machining  

NASA Technical Reports Server (NTRS)

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.

Ransom, Clyde L.

1988-01-01

286

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

SciTech Connect

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.

Meena, A.; El Mansori, M.; Ghidossi, P. [Arts et Metiers ParisTech, LMPF-EA 4106, Rue Saint Dominique, BP 508, 51006, Chalons-en-Champagne, Cedex (France)

2011-01-17

287

Machine Tool Design and Operation Strategies for Green Manufacturing  

E-print Network

Burden Analysis for Machining Operation using LCA Method,machining including machine tool design, process planning, and machine operationmachining, strategies to reduce the energy consumption of machine tools in the design and operation

2010-01-01

288

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

PubMed Central

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

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

2014-01-01

289

Mean Machines.  

ERIC Educational Resources Information Center

Suggests scales as alternative representations of numerical concepts and operations that can be used as arithmetic-mean machines, adding machines, multiplication machines, and geometric-mean machines. (ASK)

Flores, Alfinio

1998-01-01

290

Effect of single and multi-channel electrodes application on EDM fast hole drilling performance  

Microsoft Academic Search

This paper presents a comparative experimental investigation of electrical discharge machining fast hole drilling of aerospace\\u000a alloys, namely Inconel 718 and Ti–6Al–4V. A series of experiments was carried out using electrical discharge machining process\\u000a in order to explore the influence of electrode type and material, i.e., single and multi-channel tubular electrodes made of\\u000a brass and copper materials. The comparisons were

Oguzhan Yilmaz; M. Ali Okka

2010-01-01

291

Reduction of machining errors of a three-axis machine tool by on-machine measurement and error compensation system  

Microsoft Academic Search

This paper suggests a method to reduce the machining errors of a three-axis machine tool by implementing an on-machine measurement with a touch probe. Probing errors of a touch probe and positioning errors of a machine tool, inevitably included in the measurement data, are compensated for to obtain the true machining errors for the repeated machining process. Positioning errors of

J. P. Choi; B. K. Min; S. J. Lee

2004-01-01

292

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

SciTech Connect

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.

Not Available

1987-09-01

293

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

NASA Technical Reports Server (NTRS)

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.

Jobson, Daniel J.

1990-01-01

294

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)

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.

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

1977-01-01

295

C-C1-02: Data Extraction From Text, Step 1: Preparing Test for Machine Processing  

PubMed Central

Background: Natural language processing (NLP) uses software to assist in the extraction of information from clinical text, a process usually performed entirely by chart abstractors. Before NLP can be applied the text in question must be prepared for machine processing. In research settings this pre- processing work often involves several successive and related tasks, requiring substantial amounts of time and attention from people representing various types of clinical, scientific and technical expertise. Appreciating the tasks and participants involved in pre-processing clinical text can make the work more manageable, efficient, and effective. Methods: The information presented here comes from case study analyses of three small-scale projects involving preparation of clinical text (pathology reports, radiology reports, and progress notes) for processing by the Cancer Text Information Extraction System. Supplementing these experiences is information from anecdotal conversations with natural language processing experts. Results: Ten separate pre-processing tasks were identified: obtaining source feeds, assessing completeness, de-duplication, universe description, cleaning and formatting, de-identification, database loading, sampling, preparation of the NLP system input feed, and quality assurance. Nine types of expertise or task participants required for preprocessing were identified: IRB representative, source-system manager, network/dbase administrator, programmer, statistician, investigator, informaticist, clinical domain expert, and manual chart abstractor. Conclusions: Pre-processing clinical text is an important phase and potentially challenging aspect of extracting information from clinical text using NLP. Because researchers require accurate information about the larger universe of documents or patients represented by the sampled and processed text, pre-processing can present numerous challenges, the solutions to which draw on many areas of expertise in a multi-step and sometimes iterative process.

Carrell, David

2010-01-01

296

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

NASA Technical Reports Server (NTRS)

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.

1973-01-01

297

Single Machine Scheduling and Due Date Assignment with Past-Sequence-Dependent Setup Time and Position-Dependent Processing Time  

PubMed Central

This paper considers single machine scheduling and due date assignment with setup time. The setup time is proportional to the length of the already processed jobs; that is, the setup time is past-sequence-dependent (p-s-d). It is assumed that a job's processing time depends on its position in a sequence. The objective functions include total earliness, the weighted number of tardy jobs, and the cost of due date assignment. We analyze these problems with two different due date assignment methods. We first consider the model with job-dependent position effects. For each case, by converting the problem to a series of assignment problems, we proved that the problems can be solved in O(n4) time. For the model with job-independent position effects, we proved that the problems can be solved in O(n3) time by providing a dynamic programming algorithm. PMID:25258727

Zhao, Chuan-Li; Hsu, Hua-Feng

2014-01-01

298

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)

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.

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

1976-01-01

299

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

ERIC Educational Resources Information Center

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…

International Educational Data Mining Society, 2012

2012-01-01

300

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

ERIC Educational Resources Information Center

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…

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

2010-01-01

301

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

ERIC Educational Resources Information Center

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…

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

2009-01-01

302

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

DOEpatents

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.

Lee, Ching-Pang (Cincinnati, OH); Johnson, Robert Alan (Simpsonville, SC); Wei, Bin (Mechanicville, NY); Wang, Hsin-Pang (Rexford, NY)

2002-01-01

303

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

PubMed

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

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

2014-06-01

304

Non-traditional machining techniques  

SciTech Connect

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.

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

2008-01-01

305

Machining: An Introduction  

NSDL National Science Digital Library

Basic machining processes are introduced on this site that is devoted to engineering fundamentals. Descriptions and illustrations of drilling, turning, grinding, and other common processes are provided for people with little to no prior machining knowledge. A waterjet is a non-traditional machining technology that uses high pressure streams of water with abrasive additives rather than solid cutting instruments to slice through metal and other materials.

2008-04-23

306

78 FR 68981 - Electronic Retirement Processing  

Federal Register 2010, 2011, 2012, 2013, 2014

...or SF 3100), or data or images obtained from such documents, including images stored in EDMS, that are...digital form by means of image scanning or other forms of...be acceptable records for processing by the retirement and...

2013-11-18

307

78 FR 14233 - Electronic Retirement Processing  

Federal Register 2010, 2011, 2012, 2013, 2014

...or SF 3100), or data or images obtained from such documents, including images stored in EDMS, that are...digital form by means of image scanning or other forms of...be acceptable records for processing by the retirement and...

2013-03-05

308

Measurement of an off-axis parabolic mirror using coordinates measurement machine and swing arm profilometer during the grinding process  

NASA Astrophysics Data System (ADS)

We present the measurement methods for off-axis parabolic mirrors using Coordinates Measurement Machine and Swing Arm Profilometer during the grinding process. An off-axis parabolic mirror with 1200mm in parent focal length, 360mm in off-axis displacement and 410mm in diameter is measured using the methods introduced in this paper. The convergence curves of the surface error are reported, which is reduced from 204.7?m in PV, 55.3?m in rms to 1.1?m in PV, 0.3?m in rms after 39 iterations of grinding. Besides, the measurement methods are able to control the parent focal length and off-axis displacement to less than 0.1mm tolerance. An interferometric result is presented, which validates the measurement methods.

Jing, Hongwei; Lin, Changqing; Fan, Bin; Kuang, Long; Wu, Shibin; Wu, Fan; Fan, Tianquan

2012-09-01

309

Sandia's search for environmentally sound cleaning processes for the manufacture of electronic assemblies and precision machined parts  

SciTech Connect

As part of the DOE's commitment to minimizing waste at the national laboratories and its production agencies, Sandia has embarked on a program to reduce, and where feasible, eliminate hazardous liquid waste by-products of cleaning processes used in the manufacture of electronic assemblies and precision machined parts. The program is being carried out in conjunction with three DOE production agencies: Allied Signal-Kansas City Division, EG G Mound Applied Technologies, and General Electric Neutron Devices Division. We will discuss the methodology used to coordinate such a program across the DOE complex, involving as it does, hundreds of components and thousands of DOE-specified cleaning processes. We will also discuss three specific projects to replace chlorinated solvents in cleaning manufacturing processes: (1) alternative solvents used to remove solder flux residues during electronics assembly manufacture (2) alternative solvents used in ceramic header fabrication, and (3) alternative manufacturing processes that eliminate the need for solvent cleaning of precision optical components prior to mounting. 2 refs., 3 figs., 1 tab.

Oborny, M.C.; Lopez, E.P.; Frear, D.R. (Sandia National Labs., Albuquerque, NM (USA)); Benkovich, M.G. (Allied-Signal Aerospace Co., Kansas City, MO (USA). Kansas City Div.); Salerno, R.F.; Dichiaro, J.V. (EG and G Mound Applied Technologies, Miamisburg, OH (USA)); Ostheim, D.R.; Waterbury, R. Jr. (General Electric Co., Largo, FL (USA). Neutron Devices Dept.)

1990-01-01

310

Material Processing Laser Systems For Manufacturing  

NASA Astrophysics Data System (ADS)

Raycon Corporation is a builder of quality machine tools. Combining this with applications expertise to produce high technology production machinery systems using EDM, lasers and other processing methods to solve our customers' production problems is our product. The company has several standard laser machine systems which can be constructed from standard building blocks. The number of axes and travel, the controller requirements, and the required laser type, size and manufacturer are discussed with our customers, and the system to meet their needs is decided upon. These requirements are then built into a processing system for manufacturing use. Several of these systems which are in the field are described, and their purposes and how they accomplish their task are explained. Also, types of YAG and C02 lasers available are described and their optimum use explained. Some specific examples of type versus applications are: YAG low-divergence lasers for trepanning heat-resistant alloys for jet engine turbines; YAG oscillator-amplifier lasers for percussion drilling of cooling holes in jet engine turbine blades; and several special laser machine systems for processing automotive parts are discussed. A few words on laser safety are included to allay some common fears concerning the use of laser technology in the factory environment.

Taeusch, David R.; Ruselowski, John M.

1986-11-01

311

Edm deformation monitoring at the Colima Volcano before and during the 1997-2000 activity  

NASA Astrophysics Data System (ADS)

The 1997-2000 activity at Colima Volcano began in November 1997 with a series of seismic swarms and deformations of the summit lava dome. This activity reached a climax on 20 November 1998 with the extrusion of lava, accompanied by pyroclastic flows. From 10 February 1999, the explosion activity began and continued up to the time of paper preparation. Summit deformation was detected by Electronic Distance Measurement (EDM) surveys using a single frequency distancemeter DI3000s mounted on a theodolite Wild T2. Distance measurements were carried out from three base stations utilizing nine reflectors located around the volcano edifice. Reflectors were located on three different altitudes at the volcano edifice (3250, 3450, 3850 m).. After the destruction of two summit reflectors in July 1998 we continued the EDM surveys mainly with five reflectors remaining on the north flank of the volcano. EDM distance measurements taken from November 1997 to July 1998 showed maximum cumulative distance change of 0.5 cm/day on the summit reflectors that was interpreted in terms of inflation of the volcanic edifice in response to magma movement towards the surface.. EDM variations recorded in August 1998 - February 1999 from reflectors on the north flank of the volcano may reflect further inflation before extrusion of lava on 20 November 1998 and deflation after effusion ceased in February 1999.

RAMIREZ- RUIZ, J.; JIMENEZ, S.; ALATORRE-CHAVEZ, E.; BRETON, M.

2001-12-01

312

Review of the investigation of mixture formation and combustion process using rapid compression machine and direct visualization system  

NASA Astrophysics Data System (ADS)

This paper reviews of some applications of optical visualization systems to compute the fuel-air mixing process during early stage of mixture formation in Diesel Combustion Engines. A number of studies have contributed to the understanding of fuel air mixing in DI diesel engine. This review has shown that the mixture formation process affects initial flame development. The review also found that injection pressure has a great effect on the mixture formation then the flame development and combustion characteristics. The method of the simulation of real phenomenon of diesel combustion with optical access rapid compression machine is also reviewed and experimental results are presented. The application of these methods to the investigation of diesel sprays highlights mechanisms which govern propagation and distribution of the formation of a combustible fuel-air mixture. A summary of the implementation of constant volume chamber and optical visualization system are shown in the accompanying tables and figures. The visualization of the formation process of diesel spray and its combustion in the diesel combustion chamber of diesel engine has been recognized as one of the best ways to understand the characteristics of the mixture formation.

Jaat, M.; Khalid, Amir; Manshoor, B.; Ramsy, Him

2013-12-01

313

An analysis of metropolitan land-use by machine processing of earth resources technology satellite data  

NASA Technical Reports Server (NTRS)

A successful application of state-of-the-art remote sensing technology in classifying an urban area into its broad land use classes is reported. This research proves that numerous urban features are amenable to classification using ERTS multispectral data automatically processed by computer. Furthermore, such automatic data processing (ADP) techniques permit areal analysis on an unprecedented scale with a minimum expenditure of time. Also, classification results obtained using ADP procedures are consistent, comparable, and replicable. The results of classification are compared with the proposed U. S. G. S. land use classification system in order to determine the level of classification that is feasible to obtain through ERTS analysis of metropolitan areas.

Mausel, P. W.; Todd, W. J.; Baumgardner, M. F.

1976-01-01

314

GEFCom2012 Hierarchical Load Forecasting Gradient boosting machines and Gaussian processes  

E-print Network

discusses data cleansing, section 3 is on temperature forecasting, sections 4 and 5 introduce the GBM and GP. A brief introduction to Gaussian processes is provided in Appendix A. 2. Data cleansing A sensible first the algorithms detailed below performed acceptably well without further data cleansing. No adjustments were made

Ghahramani, Zoubin

315

Blind source separation: a new pre-processing tool for rotating machines monitoring?  

Microsoft Academic Search

Blind source separation (BSS) is a general signal processing method, which consists of recovering from a finite set of observations recorded by sensors, the contributions of different physical sources independently of the propagation medium and without any a priori knowledge of the sources. Recently, these methods paved a new way for the monitoring or the diagnosis of mechanical systems in

Guillaume Gelle; Maxime Colas; Christine Servière

2003-01-01

316

Machine Shop Grinding Machines.  

ERIC Educational Resources Information Center

This curriculum manual is one in a series of machine shop curriculum manuals intended for use in full-time secondary and postsecondary classes, as well as part-time adult classes. The curriculum can also be adapted to open-entry, open-exit programs. Its purpose is to equip students with basic knowledge and skills that will enable them to enter the…

Dunn, James

317

Machine Learning and NLP Research Interests  

E-print Network

Machine Learning and NLP Research Interests Machine Learning for Language Learning and Processing University of Edinburgh keller@inf.ed.ac.uk October 15, 2008 Goldwater et al. Machine Learning for Language 1 #12;Machine Learning and NLP Research Interests 1 Machine Learning and NLP Latent Variables Multi

Edinburgh, University of

318

Machining of uranium and uranium alloys  

SciTech Connect

Uranium and uranium alloys can be readily machined by conventional methods in the standard machine shop when proper safety and operating techniques are used. Material properties that affect machining processes and recommended machining parameters are discussed. Safety procedures and precautions necessary in machining uranium and uranium alloys are also covered. 30 figures.

Morris, T.O.

1981-12-14

319

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

PubMed

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 ? peptide (A?) and tau in Alzheimer's disease, ?-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 A? assembly relevant in Alzheimer's disease. PMID:25451064

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

2014-10-25

320

Production prove-out of a process for remelting depleted-uranium machining chips by vacuum induction. Final report, October 1983-October 1984  

SciTech Connect

An MM and T program to pursue a production prove-out of recycling depleted uranium machining chips in an existing vacuum-induction remelting system was conducted. A viable method of processing DU chips and generating briquettes for remelting was developed. A pilot lot of 80 finished, machined M833 penetrators, fabricated under the guidelines of this program, is available for ballistic testing. Included in this report is a general analysis of facility requirements to implement chip recycling into the Aerojet production cycle.

Skillern, C.G.; Vogel, R.L.

1985-03-01

321

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

NASA Astrophysics Data System (ADS)

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(?) 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(?) 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.

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

2014-09-01

322

Using machine learning techniques to interpret results from discrete event  

E-print Network

Using machine learning techniques to interpret results from discrete event simulation Dunja Mladeni machine learning techniques. The results of two simulators were processed as machine learning problems discovered. Key words: discrete event simulation, machine learning, artificial intelligence 1 Introduction

Mladenic, Dunja

323

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

SciTech Connect

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.

Seiz, J.B.

1997-04-01

324

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

NASA Astrophysics Data System (ADS)

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%.

Fang, Cheng; Butler, David Lee

2013-05-01

325

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

SciTech Connect

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.

Yoshimi, A. [RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Asahi, K.; Inoue, T.; Uchida, M.; Hatakeyama, N.; Tsuchiya, M.; Kagami, S. [Department of Physics, Tokyo Institute of Technology, Oh-okayama 2-12-1, Meguro, Tokyo 152-8551 (Japan)

2009-08-04

326

Broadband Velocity Modulation Spectroscopy of Molecular Ions for Use in the Jila Electron Edm Experiment  

NASA Astrophysics Data System (ADS)

The JILA electron electric dipole moment (eEDM) experiment will use a low-lying, metastable ^3?_1 state in trapped molecular ions of HfF^+ or ThF^+. Prior to this work, the low-lying states of these molecules had been investigated by PFI-ZEKE spectroscopy. However, there were no detailed studies of the electronic structure. The recently developed technique of frequency comb velocity modulation spectroscopy (VMS) provides broad-bandwidth, high-resolution, ion-sensitive spectroscopy, allowing the acquisition of 150 cm^{-1} of continuous spectra in 30 minutes over 1500 simultaneous channels. By supplementing this technique with cw-laser VMS, we have investigated the electronic structure of HfF^+ in the frequency range of 9950 to 14600 cm^{-1}, accurately fitting and assigning 16 rovibronic transitions involving 8 different electronic states including the X^1?^+ and a^3?_1 states. In addition, an observed ^3?_{0+} state with coupling to both the X and a states has been used in the actual eEDM experiment to coherently transfer population from the rovibronic ground state of HfF^+ to the eEDM science state. Furthermore, we report on current efforts of applying frequency comb VMS at 700 - 900 nm to the study of ThF^+, which has a lower energy ^3?_1 state and a greater effective electric field, and will provide increased sensitivity for a measurement of the eEDM. A. E. Leanhardt et. al., Journal of Molecular Spectroscopy 270, 1-25 (2011). B. J. Barker, I. O. Antonov, M. C. Heaven, K. A. Peterson, Journal of Chemical Physics 136, 104305 (2012). L. C. Sinclair, K. C. Cossel, T. Coffey, J. Ye, E. A. Cornell, Physical Review Letters 107, 093002 (2011). K.C. Cossel et. al., Chemical Physics Letters 546, 1-11 (2012).

Gresh, Daniel N.; Cossel, Kevin C.; Cornell, Eric A.; Ye, Jun

2013-06-01

327

Development of plasma chemical vaporization machining  

Microsoft Academic Search

Conventional machining processes, such as turning, grinding, or lapping are still applied for many materials including functional ones. But those processes are accompanied with the formation of a deformed layer, so that machined surfaces cannot perform their original functions. In order to avoid such points, plasma chemical vaporization machining (CVM) has been developed. Plasma CVM is a chemical machining method

Yuzo Mori; Kazuto Yamauchi; Kazuya Yamamura; Yasuhisa Sano

2000-01-01

328

Linear programming analysis of the $R$-parity violation within EDM-constraints  

E-print Network

The constraint on the $R$-parity violating supersymmetric interactions is discussed in the light of current experimental data of the electric dipole moment of neutron, $^{129}$Xe , $^{205}$Tl, and $^{199}$Hg atoms, and YbF and ThO molecules. To investigate the constraints without relying upon the assumption of the dominance of a particular combination of couplings over all the rest, an extensive use is made of the linear programming method in the scan of the parameter space. We give maximally possible values for the EDMs of the proton, deuteron, $^3$He nucleus, $^{211}$Rn, $^{225}$Ra, $^{210}$Fr, and the $R$-correlation of the neutron beta decay within the constraints from the current experimental data of the EDMs of neutron, $^{129}$Xe, $^{205}$Tl, and $^{199}$Hg atoms, and YbF and ThO molecules using the linear programming method. It is found that the $R$-correlation of the neutron beta decay and hadronic EDMs are very useful observables to constrain definite regions of the parameter space of the $R$-parity violating supersymmetry.

Nodoka Yamanaka; Toru Sato; Takahiro Kubota

2014-06-14

329

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

SciTech Connect

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.

Hennings-Yeomans, R.; Cooper, M.; Currie, S. A.; Makela, M. F.; Ramsey, J. C.; Tajima, S.; Womack, T. L. [Physics Division, Los Alamos National Laboratory, Los Alamos NM 87545 (United States); Long, J. C. [Department of Physics, Indiana University, 727 E. Third St. Bloomington, IN 47405-7105 (United States); Stanislaus, S. [Department of Physics and Astronomy, Valparaiso University, Valparaiso, IN 46383 (United States)

2010-08-04

330

Linear programming analysis of the R-parity violation within EDM-constraints  

NASA Astrophysics Data System (ADS)

The constraint on the R-parity violating supersymmetric interactions is discussed in the light of current experimental data of the electric dipole moment of neutron, 129Xe , 205Tl, and 199Hg atoms, and YbF and ThO molecules. To investigate the constraints without relying upon the assumption of the dominance of a particular combination of couplings over all the rest, an extensive use is made of the linear programming method in the scan of the parameter space. We give maximally possible values for the EDMs of the proton, deuteron, 3He nucleus, 211Rn, 225Ra, 210Fr, and the R-correlation of the neutron beta decay within the constraints from the current experimental data of the EDMs of neutron, 129Xe, 205Tl, and 199Hg atoms, and YbF and ThO molecules using the linear programming method. It is found that the R-correlation of the neutron beta decay and hadronic EDMs are very useful observables to constrain definite regions of the parameter space of the R-parity violating supersymmetry.

Yamanaka, Nodoka; Sato, Toru; Kubota, Takahiro

2014-12-01

331

Near net shape processing of RE–Ba–Cu–O bulk superconductor by machining binder-added precursors  

Microsoft Academic Search

Several practical applications of melt-textured bulk superconductors require the complex-shaped products such as curved, ring-shaped, and drilled blocks rather than simple shaped pellets. In general, complex-shaped bulk products are prepared by machining melt-grown massive blocks. However, melt-textured bulks are often damaged when they are mechanically machined. With the aim of reducing such damages, we have investigated the preparation of the

M. Fujikura; S. Nariki; N. Sakai; I. Hirabayashi; M. Murakami

2005-01-01

332

Numerical and experimental study on the effect of vibration of the tool in ultrasonic assisted EDM  

Microsoft Academic Search

In this paper the effect of ultrasonic vibration of the tool in the process of electrical discharge machining is investigated.\\u000a The ultrasonic vibration of the tool has significant effect on the dynamic behaviour of the vapour bubble generated between\\u000a the tool and the workpiece due to the electrical discharge. The computational simulation of the bubble behaviour is carried\\u000a out by

Mohammad T. Shervani-Tabar; Amir Abdullah; Mohammad R. Shabgard

2007-01-01

333

Kid Machine  

NSDL National Science Digital Library

This activity is on page 3 (continued on page 2) of the pdf, part of the Simple Machines Discovery Box. In this fun activity, learners "create" a complex machine by simulating the parts in action. Learners move their bodies and make sounds as if they are individual parts of a moving machine. Then learners discover what happens when part of a machine is broken and problem solve ways to fix it.

2012-06-26

334

Simple Machines  

NSDL National Science Digital Library

This is an online activity about simple machines. Learners will try their hand at putting these amazing devices to work. They will use several simple machines to help "build" a tree house. This is an excellent activity to demonstrate how science - in particular, simple machines - are at work in our everyday lives.

Cosi

2000-01-01

335

Electrostatic Machines  

NSDL National Science Digital Library

This website from Antonio Carlos M. De Queiroz, an associate professor at the Federal University of Rio de Janeiro, illustrates a number of different electrostatic machines. The site includes details and images of machines built by the professor as well as many other historical machines of this type. Some information is also available in Portugese.

De Queiroz, Antonio C.

2011-07-13

336

Simple Machines  

NSDL National Science Digital Library

This is a lesson about simple machines and how they relate to robots. Learners will gain an understanding of simple machines and how they may be used in our everyday lives. Students will also have an opportunity to design a Rube Goldberg Machine of their own. This is lesson 10 of 16 in the MarsBots learning module.

337

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

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.

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

2014-08-01

338

Advanced balancing using laser machining  

NASA Astrophysics Data System (ADS)

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.

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

1991-09-01

339

Experimental study of micro electrical discharge machining discharges  

NASA Astrophysics Data System (ADS)

Micro electrical discharge machining (?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 ?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 ?m gap sizes, 3-10 000 ?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 ne is obtained by optical emission spectroscopy diagnostics of the H?-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.

Bragança, I. M. F.; Rosa, P. A. R.; Dias, F. M.; Martins, P. A. F.; Alves, L. L.

2013-06-01

340

Meso-Machining Capabilities  

SciTech Connect

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, femtosecond 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 mechanical components and actuators which require meso-scale parts fabricated in a variety of materials. Subtractive meso-scale manufacturing processes expand the functionality of meso-scale components and complement silicon based MEMS and LIGA technologies.

BENAVIDES,GILBERT L.; ADAMS,DAVID P.; YANG,PIN

2001-06-01

341

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

NASA Astrophysics Data System (ADS)

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.

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

2011-04-01

342

DNA-based machines.  

PubMed

The base sequence in nucleic acids encodes substantial structural and functional information into the biopolymer. This encoded information provides the basis for the tailoring and assembly of DNA machines. A DNA machine is defined as a molecular device that exhibits the following fundamental features. (1) It performs a fuel-driven mechanical process that mimics macroscopic machines. (2) The mechanical process requires an energy input, "fuel." (3) The mechanical operation is accompanied by an energy consumption process that leads to "waste products." (4) The cyclic operation of the DNA devices, involves the use of "fuel" and "anti-fuel" ingredients. A variety of DNA-based machines are described, including the construction of "tweezers," "walkers," "robots," "cranes," "transporters," "springs," "gears," and interlocked cyclic DNA structures acting as reconfigurable catenanes, rotaxanes, and rotors. Different "fuels", such as nucleic acid strands, pH (H?/OH?), metal ions, and light, are used to trigger the mechanical functions of the DNA devices. The operation of the devices in solution and on surfaces is described, and a variety of optical, electrical, and photoelectrochemical methods to follow the operations of the DNA machines are presented. We further address the possible applications of DNA machines and the future perspectives of molecular DNA devices. These include the application of DNA machines as functional structures for the construction of logic gates and computing, for the programmed organization of metallic nanoparticle structures and the control of plasmonic properties, and for controlling chemical transformations by DNA machines. We further discuss the future applications of DNA machines for intracellular sensing, controlling intracellular metabolic pathways, and the use of the functional nanostructures for drug delivery and medical applications. PMID:24647836

Wang, Fuan; Willner, Bilha; Willner, Itamar

2014-01-01

343

MACHINE LEARNING FOR MULTI-MODALITY GENOMIC SIGNAL PROCESSING Sun-Yuan Kung and Man-Wai Mak  

E-print Network

in this respect. To further facilitate multi-modality fusion, a diver- sity of features may be extracted from each sensor by computational means. This is called feature di- versity. There are two basic fusion level of tens of thousands of genes, a promising advance towards a genome-wide exploration. Machine

Mak, Man-Wai

344

Cognitive signal processing: An emerging technology for the prediction of behavior of complex human\\/machine systems  

Microsoft Academic Search

One of the themes of central interest, to the public and private sectors alike, is the prediction of the behavior of complex human\\/animal\\/machine systems. Typical examples of such systems are the national economy, education systems, transportation systems, etc., as well as individual humans and animals viewed anatomically and physiologically as complex systems. This lecture presented a new approach to the

R. J. P. de Figueiredo

2009-01-01

345

Machine Tool Software  

NASA Technical Reports Server (NTRS)

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.

1988-01-01

346

: Helmholtz machine estimation .  

E-print Network

: Helmholtz machine density estimation . . : . . . (supervised learning) , (active learning) (query learning) [1, 3]. . (unsupervised learning), . , [5]. . Helmholtz machine , . Helmholtz machine : Helmholtz machine [2] . Helmholtz machine (generative network) (recognition network) . , , . Helmholtz machine (self

347

Kicking Machine  

NSDL National Science Digital Library

In this design challenge activity, learners build a machine that kicks a Ping-Pong ball into a cup lying on its side 12 inches away. Learners use a pendulum, a rubber band, or a combination of the two to do this and test the accuracy of their machines by shooting a Ping-Pong ball into a cup. Educators can use this activity to demonstrate simple machines and kinetic/potential energy. This activity can be followed up with "Extreme Kicking Machine" which adds an even greater challenge into the mix.

2012-08-20

348

Multi-objective optimization of process parameters in Electro-Discharge Diamond Face Grinding based on ANN-NSGA-II hybrid technique  

NASA Astrophysics Data System (ADS)

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.

Yadav, Ravindra Nath; Yadava, Vinod; Singh, G. K.

2013-09-01

349

Weka Machine Learning Project  

NSDL National Science Digital Library

If you are inspired to try the process, the Weka Machine Learning Project from Waikato University offers open source software that can be used for data mining tasks. Visitors can also find the projects 1993 to 2006 publications, many of which are available for free in as PDFs. The "related" section offers a number of links to further information on topics such as artificial intelligence and machine learning.

350

Human-machine interactions  

DOEpatents

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.

Forsythe, J. Chris (Sandia Park, NM); Xavier, Patrick G. (Albuquerque, NM); Abbott, Robert G. (Albuquerque, NM); Brannon, Nathan G. (Albuquerque, NM); Bernard, Michael L. (Tijeras, NM); Speed, Ann E. (Albuquerque, NM)

2009-04-28

351

Magnetic Shielding Studies for the nEDM Experiment at the SNS  

NASA Astrophysics Data System (ADS)

The nEDM Experiment at the SNS requires an overall magnetic shielding factor of order 10^5 to attenuate external background magnetic fields. At present, the shielding design includes an external (room-temperature) multi-layer ?-metal magnetic shield, a cryogenic (4 Kelvin) Pb superconducting shield, and a cryogenic (4 Kelvin) ferromagnetic shield composed of a Metglas winding. This presentation will discuss results from a number of R&D prototyping studies on the magnetic shielding design we have completed, including the formation of ?-metal to ?-metal magnetic seals across shielding gaps, optimized winding patterns for Metglas shields, studies of degaussing cycles, and methods for external background-field stabilization.

Malkowski, Susan; Plaster, Brad

2010-11-01

352

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

NASA Astrophysics Data System (ADS)

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.

Karcz, Maciej

353

Diamond machine tool face lapping machine  

DOEpatents

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.

Yetter, H.H.

1985-05-06

354

Effect of ultrasonic vibration of tool on electrical discharge machining of cemented tungsten carbide (WC-Co)  

Microsoft Academic Search

This paper deals with the effect of copper tool vibration with ultrasonic (US) frequency on the electrical discharge machining\\u000a (EDM) characteristics of cemented tungsten carbide (WC-Co). It was found that ultrasonic vibration of the tool (USVT) was\\u000a more effective in attaining a high material removal rate (MRR) when working under low discharge currents and low pulse times\\u000a (finishing regimes). In

Amir Abdullah; Mohammad R. Shabgard

2008-01-01

355

Machine learning and radiology.  

PubMed

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

Wang, Shijun; Summers, Ronald M

2012-07-01

356

Machine Learning and Radiology  

PubMed Central

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

Wang, Shijun; Summers, Ronald M.

2012-01-01

357

Electric machine  

SciTech Connect

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.

El-Refaie, Ayman Mohamed Fawzi (Niskayuna, NY); Reddy, Patel Bhageerath (Madison, WI)

2012-07-17

358

Simple Machines  

NSDL National Science Digital Library

How do you get a glove and a ball up to your tree house? One answer is to use a pulley. A pulley is a simple machine. In this original KET interactive, children learn about the basic workings of three simple machines.

2010-11-03

359

Nonplanar machines  

SciTech Connect

This talk examines methods available to minimize, but never entirely eliminate, degradation of machine performance caused by terrain following. Breaking of planar machine symmetry for engineering convenience and/or monetary savings must be balanced against small performance degradation, and can only be decided on a case-by-case basis. 5 refs.

Ritson, D. (Stanford Linear Accelerator Center, Menlo Park, CA (USA))

1989-05-01

360

Simple Machines  

NSDL National Science Digital Library

In this physical science mini-unit designed for grade 8 students, six groups of students each specialize in one of the six simple machines. As outlined here, the unit covers three to four class periods and deals with forces and motion, work and machines, and mechanical advantage. The teacher introduces students to these topics using the included PowerPoint presentation. Student groups do library or Internet research on their particular simple machine and then experiment with it in class. In culminating oral presentations, each group explains the function(s) of their machine, its mechanical advantage, and some of its everyday uses. The unit plan contains a worksheet for each simple machine group, a notes sheet, teacher pointers, and an assessment rubric.

Spaulding, Anna

2004-01-01

361

Machine coolant recycling system  

SciTech Connect

Machining processes at the 272W Site Fabrication Services (SFS) produce a waste stream consisting of dirty machine coolant. During use the coolant becomes contaminated with metal chips from milling, and oil, dirt and solvents from the machining process. The mixture is designated as a Washington State dangerous waste with WP02 (persistence), D007 (chromium) and D008 (lead) waste codes. This process results in the generation of 13.5 m{sup 3} of hazardous waste per year with an annual cost for coolant replacement, waste management and waste disposal of approximately $137,000. To identify alternatives to this situation, ICF Kaiser Hanford Company (ICF KH) North Environmental Services conducted a pollution prevention opportunity assessment (P20A) on the machining processes. A coolant recycler and sump sucker unit were selected as the most cost-effective waste reduction options. In December 1994, ICF KH received return on investment (ROI) funding from the U.S. Department of Energy Richland Operations Office (DOE-RL) to implement this option. The coolant recycling and the sump sucker units were purchased and installed in July 1995 at a total cost of $61,000. The sump sucker removes the dirty coolant from the fabrication machinery and filters it to remove shavings and sludge. The filtered coolant then is transferred to the coolant recycling system for further processing. The coolant recycling system reconditions the filtered coolant for use in the machining equipment, and mixes the concentrated coolant to the correct concentration. As a result of implementing this option, the annual generation of waste coolant was reduced by 12 m{sup 3}. The annual cost savings exceed $119,000 with an ROI of 186%. Additional benefits include reduced coolant usage; improved tool life, wheel life, finish, size control, corrosion protection, and operator working conditions; increase machine {open_quotes}up-time{close_quotes}; and reduced machine tool maintenance.

Grabner, T.A. [ICF Kaiser Hanford Company, Richland, WA (United States)

1996-12-31

362

Micro Machining Enhances Precision Fabrication  

NASA Technical Reports Server (NTRS)

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.

2007-01-01

363

Study of Airborne Dust Emission and Process Performance During Dry Machining of Aluminum-Silicon Alloy with PCD and CVD Diamond-Coated Tools  

Microsoft Academic Search

The generation of a fine mist of cutting fluid during conventional wet machining and the associated environmental and operator health concerns make environmentally benign machining and manufacturing a major research thrust both in the scientific and manufacturing communities. In this context, high-speed machining in combination with environmentally benign methods makes diamond-coated tooling a unique candidate for dry machining. Diamond coating

Prabhu U. Arumugam; Ajay P. Malshe; Stephen A. Batzer; Deepak G. Bhat

2003-01-01

364

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

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.

Hardt, D.E.; Masubuchi, K.; Paynter, H.M.; Unkel, W.C.

1983-04-01

365

Scribbling Machines  

NSDL National Science Digital Library

In this activity, learners explore electronics and motion by making a Scribbling Machine, a motorized contraption that moves in unusual ways and leaves a mark to trace its path. Itâs made from simple materials and is based on the idea of motion created by an offset motor. Try using harvested motors and switches from discarded toys and electronics to make your Scribbling Machine - this not only keeps costs down, but is a playful and inventive way to explore how everyday objects work. To take the activity further, you can also incorporate PicoCrickets to make your Scribbling Machine more intelligent and to explore computers.

Exploratorium

2013-01-30

366

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

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…

Texas State Technical Coll. System, Waco.

367

On Machine Capacitance Dimensional and Surface Profile Measurement System  

NASA Technical Reports Server (NTRS)

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.

Resnick, Ralph

1993-01-01

368

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

ERIC Educational Resources Information Center

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…

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

2011-01-01

369

Math Machines  

NSDL National Science Digital Library

The mission of the Math Machines organization is to "improve the quality of mathematical education, enhance the transfer of mathematical thinking into other classes, and increase students' ability to apply rigorous mathematics outside the classroom." Their website supports a National Science Foundation ATE grant-supported project designed to improve teaching in the areas of Mathematics, Science, and Technology at the high school and college levels. This improved learning results from using math, science, and technology principles to build and control various machines such as pointers and robots or "math machines", which are simple devices that provide an immediate, physical, dynamic expression to abstract mathematical equations. The website provides information links on Educational Theory, Classroom Activities, Project Workshops, Calculators & Programs, and Machine Construction Instructions for Building: Closed Circuits, Servo Motors, Controllers, Robot Boards and more. There is also contact information, an FAQ section, as well as upcoming events.

2010-05-18

370

Machine processing of remotely sensed data; Proceedings of the Fifth Annual Symposium, Purdue University, West Lafayette, Ind., June 27-29, 1979  

NASA Technical Reports Server (NTRS)

Papers are presented on techniques and applications for the machine processing of remotely sensed data. Specific topics include the Landsat-D mission and thematic mapper, data preprocessing to account for atmospheric and solar illumination effects, sampling in crop area estimation, the LACIE program, the assessment of revegetation on surface mine land using color infrared aerial photography, the identification of surface-disturbed features through a nonparametric analysis of Landsat MSS data, the extraction of soil data in vegetated areas, and the transfer of remote sensing computer technology to developing nations. Attention is also given to the classification of multispectral remote sensing data using context, the use of guided clustering techniques for Landsat data analysis in forest land cover mapping, crop classification using an interactive color display, and future trends in image processing software and hardware.

Tendam, I. M. (editor); Morrison, D. B.

1979-01-01

371

Man Machine Systems in Education.  

ERIC Educational Resources Information Center

This review of the research literature on the interaction between humans and computers discusses how man machine systems can be utilized effectively in the learning-teaching process, especially in secondary education. Beginning with a definition of man machine systems and comments on the poor quality of much of the computer-based learning material…

Sall, Malkit S.

372

Muonium production target for the muon g-2/EDM experiment at J-PARC  

NASA Astrophysics Data System (ADS)

There is more than three standard-deviations discrepancy between measurement and theoretical prediction of the muon anomalous magnetic moment. We are going to measure the precision value of muon g - 2 and search for physics beyond standard model. In addition, we can search for muon EDM which violates CP symmetry. CP violation in charged lepton sector is currently not found. We are developing the 'Ultra Cold Muon Beam' instead of tertiary muon beam with electric focusing. Ultra cold muon is realized by laser ionization of muonium (bound state of a muon and an electron) from the production target. Increase of muonium yield is essential for our experimental goal; 0.1ppm statistical precision. Muonium production experiment at J-PARC MLF MUSE is planned in 2012 autumn. In this paper, we discuss the development of muonium production target and positron detector for the study.

Kanda, Sohtaro

2014-08-01

373

Modeling Systematic Error Effects for a Sensitive Storage Ring EDM Polarimeter  

NASA Astrophysics Data System (ADS)

The Storage Ring EDM Collaboration has obtained a set of measurements detailing the sensitivity of a storage ring polarimeter for deuterons to small geometrical and rate changes. Various schemes, such as the calculation of the cross ratio [1], can cancel effects due to detector acceptance differences and luminosity differences for states of opposite polarization. Such schemes fail at second-order in the errors, becoming sensitive to geometrical changes, polarization magnitude differences between opposite polarization states, and changes to the detector response with changing data rates. An expansion of the polarimeter response in a Taylor series based on small errors about the polarimeter operating point can parametrize such effects, primarily in terms of the logarithmic derivatives of the cross section and analyzing power. A comparison will be made to measurements obtained with the EDDA detector at COSY-J"ulich. [4pt] [1] G.G. Ohlsen and P.W. Keaton, Jr., NIM 109, 41 (1973).

Stephenson, Edward; Imig, Astrid

2009-10-01

374

Trepanning of Al 2O 3 by electro-chemical discharge machining (ECDM) process using abrasive electrode with pulsed DC supply  

Microsoft Academic Search

Electro-chemical discharge machining (ECDM) of electrically non-conductive high-strength–high-temperature-resistant ceramics such as aluminium oxide (Al2O3) by trepanning method (i.e. orbital motion of tool) has shown the possibility of drilling large size holes by comparatively smaller electrodes efficiently and economically. However, at greater machined depth, the conventional electrode configurations and machining parameters show that machining performance gradually deteriorates with increase in tool

Sanjay K. Chak; P. Venkateswara Rao

2007-01-01

375

Drum cutter mining machine  

Microsoft Academic Search

A drum cutter mining machine includes a machine frame with a winch having a drive wheel to engage a rack or chain which extends along the path of travel by the mining machine to propel the machine along a mine face. The mining machine is made up of discrete units which include a machine body and machine housings joined to

K. Oberste-beulmann; H. Schupphaus

1980-01-01

376

The Answer Machine.  

ERIC Educational Resources Information Center

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;…

Feldman, Susan

2000-01-01

377

Introduction to Exploring Machines  

ERIC Educational Resources Information Center

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…

Early Childhood Today, 2006

2006-01-01

378

Machining in Microgravity  

Microsoft Academic Search

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

Graylan Vincent

2003-01-01

379

Simulating Turing Machines on Maurer Machines  

E-print Network

Simulating Turing Machines on Maurer Machines J.A. Bergstra1,2 and C.A. Middelburg3 1 Programming MB Eindhoven, the Netherlands keesm@win.tue.nl Abstract. Maurer machines are much closer to real computers than Turing machines. Computer instructions play a prominent part in Mau- rer machines. We show

van der Zwaag, Mark

380

Culture Machine  

NSDL National Science Digital Library

Culture Machine is a new, refereed, electronic journal encompassing cultural studies and cultural theory. The international editorial board of the interactive journal aims to "generat[e] research in culture and theory" by promoting and publishing "the most provocative of new work." The theme of the inaugural issue is Taking Risks with the Future. Content includes articles such as Life After Death of the Text by Johan Fornas, Cultural Studies in the Clouds: Mourning for Detail by Tadeusz Slawek, and The Future States of Politics by Kenneth Surin. Culture Machine is hosted by the University of Teesside, England.

381

Automated fiber pigtailing machine  

DOEpatents

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.

Strand, Oliver T. (Castro Valley, CA); Lowry, Mark E. (Castro Valley, CA)

1999-01-01

382

Automated fiber pigtailing machine  

DOEpatents

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.

Strand, O.T.; Lowry, M.E.

1999-01-05

383

Machinability of Stellite 6 hardfacing  

NASA Astrophysics Data System (ADS)

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.

Benghersallah, M.; Boulanouar, L.; Le Coz, G.; Devillez, A.; Dudzinski, D.

2010-06-01

384

Monitoring machine operations using on-line sensors  

Microsoft Academic Search

Monitoring machine operations and production process conditions using on-line sensors has drawn increasing attention recently. In this paper, we discuss a situation where an on-line sensor is used to monitor a randomly deteriorating machine operation. The machine condition is described by a finite number of states, and the machine deterioration follows a Markov process. It is assumed that the sensor

Linguo Gong; Kwei Tang

1997-01-01

385

Applications of Machine Learning in Information Retrieval.  

ERIC Educational Resources Information Center

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…

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

1999-01-01

386

Mechanisms and economy of molecular machines  

NASA Astrophysics Data System (ADS)

Cells contain millions of biomolecules that function as molecular machines. This paper reviews aspects of the mechanisms of these machines (alternative pathways and cooperativity) as well as the economic principles of their use in cells. The focus is on the machines that process the genetic information, in particular RNA polymerases.

Klumpp, Stefan

2012-11-01

387

Function Machine  

NSDL National Science Digital Library

This Java applet allows learners to explore simple linear functions. Students determine the algebraic form of a linear equation by entering inputs into the machine and by looking for patterns in the outputs. The function rules available are: integers from -10 to 10 are either added to, subtracted from, or multiplied by the input x to yield the output y.

2011-01-01

388

Decoding Machine  

NSDL National Science Digital Library

In this math lesson, learners explore variables and their uses. Learners pretend to be FBI agents and make a TOP SECRET tool that enables them to decode and find the values of hidden messages and words. Learners make their simple "decoding machines" out of paper and tape.

Lessonplans, Utah

2012-10-22

389

Leonardo's Machines  

NSDL National Science Digital Library

This Science NetLinks lesson will highlight some of Leonardo da Vinci's futuristic inventions, introducing the elements of machines. Through the use of student interactives, this lesson provides an interesting context in which students can begin to develop their ideas about the uniqueness of humans in the natural world.

Science Netlinks;

2003-03-05

390

Topic in Depth - Precision Machining  

NSDL National Science Digital Library

As technology advances and devices become smaller and more complex, the need for precision manufacturing processes is becoming increasingly important. A number of innovative techniques for precision machining have been developed to enable the construction and operation of such contrivances.

391

Reduce cycle time and work in process in a medical device factory : scheduling of needle hub molding machines  

E-print Network

Many manufacturing firms have improved their operations by implementing a work-in-process (WIP) limiting control strategy. This project explores the application of this concept to limit WIP and reduce cycle time for the ...

Yao, Jing, M. Eng. Massachusetts Institute of Technology

2007-01-01

392

Reduce cycle time and work in process in a medical device factory : scheduling policies for needle assembly machine  

E-print Network

Many manufacturing firms have improved their operations by implementing a work-in-process (WIP) limiting control strategy. This project explores the application of this concept to limit WIP and reduce cycle time for the ...

Meng, Kai, M. Eng. Massachusetts Institute of Technology

2007-01-01

393

Discrimination of raw and processed Dipsacus asperoides by near infrared spectroscopy combined with least squares-support vector machine and random forests  

NASA Astrophysics Data System (ADS)

Most herbal medicines could be processed to fulfill the different requirements of therapy. The purpose of this study was to discriminate between raw and processed Dipsacus asperoides, a common traditional Chinese medicine, based on their near infrared (NIR) spectra. Least squares-support vector machine (LS-SVM) and random forests (RF) were employed for full-spectrum classification. Three types of kernels, including linear kernel, polynomial kernel and radial basis function kernel (RBF), were checked for optimization of LS-SVM model. For comparison, a linear discriminant analysis (LDA) model was performed for classification, and the successive projections algorithm (SPA) was executed prior to building an LDA model to choose an appropriate subset of wavelengths. The three methods were applied to a dataset containing 40 raw herbs and 40 corresponding processed herbs. We ran 50 runs of 10-fold cross validation to evaluate the model's efficiency. The performance of the LS-SVM with RBF kernel (RBF LS-SVM) was better than the other two kernels. The RF, RBF LS-SVM and SPA-LDA successfully classified all test samples. The mean error rates for the 50 runs of 10-fold cross validation were 1.35% for RBF LS-SVM, 2.87% for RF, and 2.50% for SPA-LDA. The best classification results were obtained by using LS-SVM with RBF kernel, while RF was fast in the training and making predictions.

Xin, Ni; Gu, Xiao-Feng; Wu, Hao; Hu, Yu-Zhu; Yang, Zhong-Lin

2012-04-01

394

Machine Learning  

NASA Astrophysics Data System (ADS)

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.

Hoffmann, Achim; Mahidadia, Ashesh

395

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)

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%.

Klilou, Abdessamad; Belkouch, Said; Elleaume, Philippe; Le Gall, Philippe; Bourzeix, François; Hassani, Moha M'Rabet

2014-12-01

396

State-Machine Replication  

E-print Network

State-Machine Replication #12;The Problem Clients Server #12;The Problem Clients Server #12;The (state machine) #12;The Solution 1. Make server deterministic (state machine) State machine #12;The Solution 1. Make server deterministic (state machine) 2. Replicate server State machines #12;The Solution 1

Venkataramani, Arun

397

Simple Machines  

NSDL National Science Digital Library

Can you identify the six types of simple machines? 1. What do you know about Inclined Planes? Draw an example on your graphic organizer and state one fact.Inclined Plane 2. What do you know about levers? Draw an example on your graphic organizer and state one fact.Lever. 3. What do you know about pulleys? Draw an example on your graphic organizer and ...

Stewart, Miss

2010-03-24

398

Induction machine  

DOEpatents

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.

Owen, Whitney H. (Ogden, UT)

1980-01-01

399

An intelligent CNC machine control system architecture  

SciTech Connect

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.

Miller, D.J.; Loucks, C.S.

1996-10-01

400

Non-traditional ProcessingNon traditional Processing ME 4210: Manufacturing Processes and Engineering  

E-print Network

and Engineering Prof. J.S. Colton © GIT 2009 1 #12;ProcessesProcesses · Chemical machining El h i l hi i Processes and Engineering Prof. J.S. Colton © GIT 2009 2 #12;Chemical MachiningChemical Machining ME 4210: Manufacturing Processes and Engineering Prof. J.S. Colton © GIT 2009 3 #12;Chemical MachiningChemical Machining

Colton, Jonathan S.

401

Symposium on Machine Processing of Remotely Sensed Data, Purdue University, West Lafayette, Ind., June 29-July 1, 1976, Proceedings  

NASA Technical Reports Server (NTRS)

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.

1976-01-01

402

Processing of A-15 Nb sub 3 Si, Nb sub 3 Ge and Nb sub 3 (AlSi) superconducting ribbons by the chill-block spinning machine  

SciTech Connect

A processing technique for A-15 compounds which has improved mechanical and superconducting properties has been developed. This technique consists of rapid solidification of the alloy by the chill block spinning machine (CBSM) to form amorphous ribbons and by subsequent annealing crystallizes the stable or metastable fine grain flexible A-15 structure. The CBSM has been modified so that all the processing parameters could be controlled and optimized for each alloy composition. By the improved CBSM it was possible to form amorphous Nb{sub 3}Si, Nb{sub 3}Ge and Nb{sub 3}(AlSi) ribbons with more than 80% reproducible rate. Critical current density measurements are limited by contact resistance. A Cu plating technique was introduced in this research that made the contact resistance three orders of magnitude lower than that obtained by other methods. This plated coating also gave an additional mechanical support to the sample and acted as a shunt for thermal stabilization of the sample. J{sub c} of Nb{sub 3}Ge at 15 Tesla was 8 {times} 10{sup 8} A/m{sup 2}. The J{sub c} of Nb{sub 3}(AlSi) at 15 Tesla was 5 {times} 10{sup 10} A/m{sup 2}. The J{sub c} value observed in the Nb{sub 3}(AlSi) alloy at 15 Tesla is the highest reported value for any superconductor as of today.

Manzur, Tariq.

1989-01-01

403

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

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

Schmithorst, Vincent J.; Farah, Rola; Keith, Robert W.

2013-01-01

404

Measurement of Systematic Error Effects for a Sensitive Storage Ring EDM Polarimeter  

NASA Astrophysics Data System (ADS)

The Storage Ring EDM Collaboration was using the Cooler Synchrotron (COSY) and the EDDA detector at the Forschungszentrum J"ulich to explore systematic errors in very sensitive storage-ring polarization measurements. Polarized deuterons of 235 MeV were used. The analyzer target was a block of 17 mm thick carbon placed close to the beam so that white noise applied to upstream electrostatic plates increases the vertical phase space of the beam, allowing deuterons to strike the front face of the block. For a detector acceptance that covers laboratory angles larger than 9 ^o, the efficiency for particles to scatter into the polarimeter detectors was about 0.1% (all directions) and the vector analyzing power was about 0.2. Measurements were made of the sensitivity of the polarization measurement to beam position and angle. Both vector and tensor asymmetries were measured using beams with both vector and tensor polarization. Effects were seen that depend upon both the beam geometry and the data rate in the detectors.

Imig, Astrid; Stephenson, Edward

2009-10-01

405

Abrasive water jet machining of glass with stagnation effect  

Microsoft Academic Search

Abrasive water jet processes of glass are presented for crack-free machining of micro grooves and fluid polishing of micro channels with CFD analysis. In machining of the micro grooves, the abrasive is supplied to flow through intended machining area using the tapered masks. Stagnation under the jet and the horizontal flow on the machining area are controlled to generate crack-free

T. Matsumura; T. Muramatsu; S. Fueki

2011-01-01

406

Dynamic monocular machine vision  

Microsoft Academic Search

A new approach to real-time machine vision in dynamic scenes is presented based on special hardware and methods for feature extraction and information processing. Using integral spatio-temporal models, it by-passes the nonunique inversion of the perspective projection by applying recursive least squares filtering. By prediction error feedback methods similar to those used in modern control theory, all spatial state variables

Ernst Dieter Dickmanns; Volker Graefe

1988-01-01

407

Machine Design  

NSDL National Science Digital Library

This website, the homepage of Machine Design.com, contains resources on a variety of information for engineers and technicians related to devices, components, design applications, products, and systems in the manufacturing technology sector. The site also features a CAD library, eBooks, audiovisual aids, webinars, whitepapers and a reference center. Some of the resources require a free login. The page offers an RSS feed to keep users up to date on new resources. A free login may be required to access some of these items.

408

RISMA: A Rule-based Interval State Machine Algorithm for Alerts Generation, Performance Analysis and Monitoring Real-Time Data Processing  

NASA Astrophysics Data System (ADS)

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.

Laban, Shaban; El-Desouky, Aly

2013-04-01

409

International Conference on Machine Control & Guidance 2008 1 New Technologies for Telematics and Machine Control  

E-print Network

1st International Conference on Machine Control & Guidance 2008 1 New Technologies for Telematics and Machine Control Achiel STURM, Willem VOS Topcon Europe 1 SITE AUTOMATION ­ DOES IT PAY OFF? Processes, but are often carried out independently. Automating a job site by utilizing machine control is a way to increase

410

One-class support vector machines—an application in machine fault detection and classification  

Microsoft Academic Search

Fast incipient machine fault diagnosis is becoming one of the key requirements for economical and optimal process operation management. Artificial neural networks have been used to detect machine faults for a number of years and shown to be highly successful in this application area. This paper presents a novel test technique for machine fault detection and classification in electro-mechanical machinery

Hyun Joon Shin; Dong-Hwan Eom; Sung-Shick Kim

2005-01-01

411

Effect of workpiece properties on machinability in abrasive jet machining of ceramic materials  

Microsoft Academic Search

Abrasive jet machining (AJM), a specialized form of shot blasting using fine-grained abrasives, is an attractive micro-machining method for ceramic materials. In this paper, the machinability during the AJM process is compared to that given by the established models of solid particle erosion, in which the material removal is assumed to originate in the ideal crack formation system. However, it

M. Wakuda; Y. Yamauchi; S. Kanzaki

2002-01-01

412

Tunneling machine  

SciTech Connect

A diametrically compact tunneling machine for boring tunnels is disclosed. The machine includes a tubular support frame having a hollow piston mounted therein which is movable from a retracted position in the support frame to an extended position. A drive shaft is rotatably mounted in the hollow piston and carries a cutter head at one end. The hollow piston is restrained against rotational movement relative to the support frame and the drive shaft is constrained against longitudinal movement relative to the hollow piston. A plurality of radially extendible feet project from the support frame to the tunnel wall to grip the tunnel wall during a tunneling operation wherein the hollow piston is driven forwardly so that the cutter head works on the tunnel face. When the hollow piston is fully extended, a plurality of extendible support feet, which are fixed to the rearward and forward ends of the hollow piston, are extended, the radially extendible feet are retracted and the support frame is shifted forwardly by the piston so that a further tunneling operation may be initiated.

Snyder, L.L.

1980-02-19

413

Course info Machine Learning  

E-print Network

Course info Machine Learning Real life problems Lecture 1: Machine Learning Problem Qinfeng (Javen) Shi 28 July 2014 Intro. to Stats. Machine Learning COMP SCI 4401/7401 Qinfeng (Javen) Shi Lecture 1: Machine Learning Problem #12;Course info Machine Learning Real life problems Table of Contents I 1 Course

Shi, Qinfeng "Javen"

414

Socially guided machine learning  

E-print Network

Social interaction will be key to enabling robots and machines in general to learn new tasks from ordinary people (not experts in robotics or machine learning). Everyday people who need to teach their machines new things ...

Thomaz, Andrea Lockerd

2006-01-01

415

Electrochemical Machining Carves out Nanostructures  

NSDL National Science Digital Library

This news article from June 20, 2003 published by Great Britain's Institute of Physics, describes an electrochemical machining process that is being used to fabricate complex nanostructures. The work, produced by German and U.S. researchers, has the potential to compete with current lithographic processes.

Kalaugher, Liz

2008-04-23

416

Analysis of Surface Characteristics of AISI D2 Tool Steel Material Using Carbon Nano Tube  

Microsoft Academic Search

Recent developments in EDM have opened up new avenues for finishing of hard and brittle materials with nano surface finish, high tolerance and accuracy. Electrical discharge machining (EDM) is one of the important non- traditional machining processes. Carbon nano tube is having high Mechanical and Electrical Properties specifically High Electrical Conductivity. By using this property the multi wall carbon nano

S. Prabhu; B. K. Vinayagam

417

Microfabrication with femtosecond laser processing : (A) laser ablation of ferrous alloys, (B) direct-write embedded optical waveguides and integrated optics in bulk glasses.  

SciTech Connect

At Sandia National Laboratories, miniaturization dominates future hardware designs, and technologies that address the manufacture of micro-scale to nano-scale features are in demand. Currently, Sandia is developing technologies such as photolithography/etching (e.g. silicon MEMS), LIGA, micro-electro-discharge machining (micro-EDM), and focused ion beam (FIB) machining to fulfill some of the component design requirements. Some processes are more encompassing than others, but each process has its niche, where all performance characteristics cannot be met by one technology. For example, micro-EDM creates highly accurate micro-scale features but the choice of materials is limited to conductive materials. With silicon-based MEMS technology, highly accurate nano-scale integrated devices are fabricated but the mechanical performance may not meet the requirements. Femtosecond laser processing has the potential to fulfill a broad range of design demands, both in terms of feature resolution and material choices, thereby improving fabrication of micro-components. One of the unique features of femtosecond lasers is the ability to ablate nearly all materials with little heat transfer, and therefore melting or damage, to the surrounding material, resulting in highly accurate micro-scale features. Another unique aspect to femtosecond radiation is the ability to create localized structural changes thought nonlinear absorption processes. By scanning the focal point within transparent material, we can create three-dimensional waveguides for biological sensors and optical components. In this report, we utilized the special characteristics of femtosecond laser processing for microfabrication. Special emphasis was placed on the laser-material interactions to gain a science-based understanding of the process and to determine the process parameter space for laser processing of metals and glasses. Two areas were investigated, including laser ablation of ferrous alloys and direct-write optical waveguides and integrated optics in bulk glass. The effects of laser and environmental parameters on such aspects as removal rate, feature size, feature definition, and ablation angle during the ablation process of metals were studied. In addition, the manufacturing requirements for component fabrication including precision and reproducibility were investigated. The effect of laser processing conditions on the optical properties of direct-written waveguides and an unusual laser-induced birefringence in an optically isotropic glass are reported. Several integrated optical devices, including a Y coupler, directional coupler, and Mach-Zehnder interferometer, were made to demonstrate the simplicity and flexibility of this technique in comparison to the conventional waveguide fabrication processes.

Guo, Junpeng; McDaniel, Karen Lynn; Palmer, Jeremy Andrew; Yang, Pin; Griffith, Michelle Lynn; Vawter, Gregory Allen; Harris, Marc F.; Tallant, David Robert; Luk, Ting Shan; Burns, George Robert

2004-11-01

418

Turing Machines A Turing machine M is  

E-print Network

to perform computations. A function f is Turing-computable iff there exists some TM M such that f(x) = y iff1 Turing Machines A Turing machine M is: Q, a set of internal states. , the input alphabet. , tape of Turing machine M on input w Initial state q0, tape w, blanks around w, read-write head at first symbol

Bylander, Tom

419

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

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.

Keller, Brad M.; Nathan, Diane L.; Wang Yan; Zheng Yuanjie; Gee, James C.; Conant, Emily F.; Kontos, Despina [Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Applied Mathematics and Computational Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

2012-08-15

420

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  

PubMed Central

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 ? ? 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. PMID:22894417

Keller, Brad M.; Nathan, Diane L.; Wang, Yan; Zheng, Yuanjie; Gee, James C.; Conant, Emily F.; Kontos, Despina

2012-01-01

421

Development of plasma chemical vaporization machining  

NASA Astrophysics Data System (ADS)

Conventional machining processes, such as turning, grinding, or lapping are still applied for many materials including functional ones. But those processes are accompanied with the formation of a deformed layer, so that machined surfaces cannot perform their original functions. In order to avoid such points, plasma chemical vaporization machining (CVM) has been developed. Plasma CVM is a chemical machining method using neutral radicals, which are generated by the atmospheric pressure plasma. By using a rotary electrode for generation of plasma, a high density of neutral radicals was formed, and we succeeded in obtaining high removal rate of several microns to several hundred microns per minute for various functional materials such as fused silica, single crystal silicon, molybdenum, tungsten, silicon carbide, and diamond. Especially, a high removal rate equal to lapping in the mechanical machining of fused silica and silicon was realized. 1.4 nm (p-v) was obtained as a surface roughness in the case of machining a silicon wafer. The defect density of a silicon wafer surface polished by various machining method was evaluated by the surface photo voltage spectroscopy. As a result, the defect density of the surface machined by plasma CVM was under 1/100 in comparison with the surface machined by mechanical polishing and argon ion sputtering, and very low defect density which was equivalent to the chemical etched surface was realized. A numerically controlled CVM machine for x-ray mirror fabrication is detailed in the accompanying article in this issue.

Mori, Yuzo; Yamauchi, Kazuto; Yamamura, Kazuya; Sano, Yasuhisa

2000-12-01

422

From human-machine interaction to human-machine cooperation.  

PubMed

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

Hoc, J M

2000-07-01

423

A REVIEW ON THE ROTARY ULTRASONIC MACHINING OF ADVANCED CERAMICS  

Microsoft Academic Search

Advanced ceramics are likely candidates for many industrial applications due to their superior properties. However, their high machining costs lead to limited applications. Rotary ultrasonic machining (RUM) is one of the cost-effective machining processes available for drilling holes in advanced ceramics. This paper reports on investigations in the last few years on RUM process of advanced ceramics. Emphasis is given

C. Y. Khoo; Esah Hamzah; Izman Sudin

2008-01-01

424

DC Machine  

NSDL National Science Digital Library

The effect of the commutator is to produce a fixed spatial distribution of current directions in the armature conductors (shown as blue & green circles) independent of shaft rotation. The field created by these currents (armature reaction) is vertically directed along the quadrature axis. The field established by the excitation of the stator poles is directed along the horizontal direct axis. This package presents computer models of electric machines based on the space vector formulation leading to the assessment of the dynamic performance of open- and closed-loopac and dc drive systems. The Simulink/Matlab implementation is adopted because of its inherent integration of vectorized system representations in block diagram form, of numerical analysis methods, of graphical portrayal of time evolutions of signals combined with the simple realization of the functionality of controllers and power electronic excitations. The development of Simulink models of drive assemblies is a relatively simple task consisting of combining input-output block representation of the various components making up the system; these blocks can readily be reused (utilizing standard copy-and-paste techniques) to modify the system components or the configuration of the system. This approach provides a powerful design tool because of the ease of observing the effects of parameters modifications and of differing system configurations and control strategies.

Riaz, Mahmoud

2012-08-29

425

All Electric Injection Molding Machines: How Much Energy Can You Save?  

E-print Network

There are three basic types of injection molding machines (IMMs) currently on the market: hydraulic, all-electric, and hybrid. They each have a different way of driving machine processes. Hydraulic IMMs use hydraulic pumps, all-electric machines use...

Kanungo, A.; Swan, E.

2008-01-01

426

IDMME 2006 Grenoble, France, May 17-19, 2006 EVALUATION OF MACHINING DISPERSIONS FOR TURNING  

E-print Network

of machining aims to simulate the operations of machining by taking into account the dispersions of machining of simulation of machining allows to simulate the behaviour of the operations of the process plan consideringIDMME 2006 Grenoble, France, May 17-19, 2006 1 EVALUATION OF MACHINING DISPERSIONS FOR TURNING

Paris-Sud XI, Université de

427

Cold machining of high density tungsten and other materials  

NASA Technical Reports Server (NTRS)

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.

Ziegelmeier, P.

1969-01-01

428

Building and simulating protein machines  

NASA Astrophysics Data System (ADS)

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.

Katebi, Ataur Rahim

429

Parametric analysis on electrochemical discharge machining of silicon nitride ceramics  

Microsoft Academic Search

The electrochemical discharge machining (ECDM) process has a potential in the machining of silicon nitride ceramics. This\\u000a paper describes the development of a second order, non-linear mathematical model for establishing the relationship among machining\\u000a parameters, such as applied voltage, electrolyte concentration and inter-electrode gap, with the dominant machining process\\u000a criteria, namely material removal rate (MRR), radial overcut (ROC) and thickness

B. R. Sarkar; B. Doloi; B. Bhattacharyya

2006-01-01

430

Decomposition of forging die for high speed machining  

E-print Network

Today's forging die manufacturing process must be adapted to several evolutions in machining process generation: CAD/CAM models, CAM software solutions and High Speed Machining (HSM). In this context, the adequacy between die shape and HSM process is in the core of machining preparation and process planning approaches. This paper deals with an original approach of machining preparation integrating this adequacy in the main tasks carried out. In this approach, the design of the machining process is based on two levels of decomposition of the geometrical model of a given die with respect to HSM cutting conditions (cutting speed and feed rate) and technological constrains (tool selection, features accessibility). This decomposition assists machining assistant to generate an HSM process. The result of this decomposition is the identification of machining features.

Tapie, Laurent

2009-01-01

431

Aerosols generated during beryllium machining.  

PubMed

Some beryllium processes, especially machining, are associated with an increased risk of beryllium sensitization and disease. Little is known about exposure characteristics contributing to risk, such as particle size. This study examined the characteristics of beryllium machining exposures under actual working conditions. Stationary samples, using eight-stage Lovelace Multijet Cascade Impactors, were taken at the process point of operation and at the closest point that the worker would routinely approach. Paired samples were collected at the operator's breathing zone by using a Marple Personal Cascade Impactor and a 35-mm closed-faced cassette. More than 50% of the beryllium machining particles in the breathing zone were less than 10 microns in aerodynamic diameter. This small particle size may result in beryllium deposition into the deepest portion of the lung and may explain elevated rates of sensitization among beryllium machinists. PMID:10652683

Martyny, J W; Hoover, M D; Mroz, M M; Ellis, K; Maier, L A; Sheff, K L; Newman, L S

2000-01-01

432

On-machine dimensional verification. Final report  

SciTech Connect

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.

Rendulic, W.

1993-08-01

433

Can Machines BeCan Machines Be Polite?Polite?  

E-print Network

Can Machines BeCan Machines Be Polite?Polite? Michael A. CovingtonMichael A. Covington Artificial Intelligence CenterArtificial Intelligence Center #12;Can machines be polite?Can machines be polite? Machines have beenMachines have been annoying peopleannoying people ever since humanever since human--machine

Covington, Michael A.

434

RELATIONSHIP BETWEEN MACHINING FORCES AND DIAMOND TOOL WEAR DURING DUCTILE REGIME MACHINING OF SILICON NITRIDE  

Microsoft Academic Search

Silicon nitride by nature is hard and brittle. In previous works, it has been demonstrated that silicon nitride can be machined by single-edge diamond tool as an alternative to the traditional finishing process. But commercial viability of such diamond turning processes is limited by tool wear. In this paper, an attempt has been made to edge machine silicon nitride disks

Ravishankar Mariayyah; John P. Patten; Harish P. Cherukuri

2012-01-01

435

Applications of machine learning and rule induction  

Microsoft Academic Search

Machine learning is the study of computational methods for improving performance by mechanizing the acquisition of knowledge from experience. Expert performance requires much domain-specific knowledge, and knowledge engineering has produced hundreds of AI expert systems that are now used regularly in industry. Machine learning aims to provide increasing levels of automation in the knowledge engineering process, replacing much time-consuming human

Pat Langley; Herbert A. Simon

1995-01-01

436

Machining of high chromium hardfacing materials  

Microsoft Academic Search

Hardfacing materials with large chromium carbide are widely used in industry to increase the wear resistance of the component. Its manufacturing process is an important aspect of the overall economy of this technology. Inclusion of large chromium carbides in its microstructure makes these materials very difficult to machine. Development of PCBN tools has opened up the possibility to machine this

X. J. Ren; R. D. James; E. J. Brookes; L. Wang

2001-01-01

437

Advances in Diagnostic Techniques for Induction Machines  

Microsoft Academic Search

This paper investigates diagnostic techniques for electrical machines with special reference to induction machines and to papers published in the last ten years. A comprehensive list of references is reported and examined, and research activities classified into four main topics: 1) electrical faults; 2) mechanical faults; 3) signal processing for analysis and monitoring; and 4) artificial intelligence and decision-making techniques.

Alberto Bellini; Fiorenzo Filippetti; Carla Tassoni; GÉrard-AndrÉ Capolino

2008-01-01

438

Machining Damage in Edge Trimming of CFRP  

Microsoft Academic Search

Conventional machining processes such as turning, milling, drilling, abrasive cutting, and grinding are commonly used to bring composite parts to final shape and assembly requirements. However, due to the layered nature of these materials, their machining may generate undesirable defects such as delamination and high surface roughness. The service life of composite components is believed to be highly dependent on

Jamal Sheikh-Ahmad; Nebu Urban; Hossein Cheraghi

2012-01-01

439

Hybrid Quantum Cloning Machine  

E-print Network

In this work, we introduce a special kind of quantum cloning machine called Hybrid quantum cloning machine. The introduced Hybrid quantum cloning machine or transformation is nothing but a combination of pre-existing quantum cloning transformations. In this sense it creates its own identity in the field of quantum cloners. Hybrid quantum cloning machine can be of two types: (i) State dependent and (ii) State independent or Universal. We study here the above two types of Hybrid quantum cloning machines. Later we will show that the state dependent hybrid quantum-cloning machine can be applied on only four input states. We will also find in this paper another asymmetric universal quantum cloning machine constructed from the combination of optimal universal B-H quantum cloning machine and universal anti-cloning machine. The fidelities of the two outputs are different and their values lie in the neighborhood of ${5/6} $

Satyabrata Adhikari; A. K. Pati; Indranil Chakrabarty; B. S. Choudhury

2007-06-14

440

Interaction with Machine Improvisation  

NASA Astrophysics Data System (ADS)

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.

Assayag, Gerard; Bloch, George; Cont, Arshia; Dubnov, Shlomo

441

Simple Machines in the Community  

ERIC Educational Resources Information Center

The community can be a powerful context and mini-laboratory for cultivating students' common understandings of science and mathematics. On the island of Panay in the Philippines, the community was the starting place for a group of fifth- and sixth-grade students to explore simple machines in their daily lives. What students learned in the process

Bryan, Robert; Laroder, Aris; Tippins, Deborah; Emaz, Meliza; Fox, Ryan

2008-01-01

442

Consequences of heavy machining vis à vis the machine structure - typical applications  

NASA Astrophysics Data System (ADS)

StarragHeckert has built 5 axis machines since the middle of the 80s for heavy duty milling. The STC-Centres are predominantly utilised in the aerospace industry, especially for milling structural workpieces, casings or Impellers made out of titanium and steel. StarragHeckert has a history of building machines for high performance milling. The machining of these components includes high forces thus spreading the wheat from the chaff. Although FEM calculations and multi-body simulations are carried out in the early stages of development, this paper will illustrate how the real process stability with modal analysis and cutting trials is determined. The experiment observes chatter stability to identify if the machine devices are adequate for the application or if the design has to be improved. Machining parameters of industrial applications are demonstrating the process stability for five axis heavy duties milling of StarragHeckert machine.

Leuch, M.

2011-12-01

443

15 CFR 700.31 - Metalworking machines.  

Code of Federal Regulations, 2013 CFR

...section include: Bending and forming machines Boring machines Broaching machines Drilling and tapping machines Electrical discharge, ultrasonic and chemical erosion machines Forging machinery and hammers Gear cutting and...

2013-01-01

444

Machine learning methods in chemoinformatics  

PubMed Central

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

Mitchell, John B O

2014-01-01

445

Gestalt: Integrated Support for Implementation and Analysis in Machine Learning  

E-print Network

Gestalt: Integrated Support for Implementation and Analysis in Machine Learning Kayur Patel present Gestalt, a development environment designed to support the process of applying machine learning this significantly improves the ability of developers to find and fix bugs in machine learning systems. Our

Anderson, Richard

446

Machine Learning in Natural Language Georgios P. Petasis  

E-print Network

Machine Learning in Natural Language Processing Georgios P. Petasis Software and Knowledge@iit.demokritos.gr Abstract. This thesis examines the use of machine learning techniques in various tasks of natural language-entity recog- nition, and b) the creation of a new machine learning algorithm and its assessment on synthetic

Kouroupetroglou, Georgios

447

Minimizing Busy Time in Multiple Machine Real-time Scheduling  

E-print Network

Minimizing Busy Time in Multiple Machine Real-time Scheduling Rohit Khandekar1 , Baruch Schieber1 with a release time, a due date, a processing time and demand for machine capacity. The goal is to schedule all of the jobs non-preemptively in their release-time-deadline windows, subject to machine capacity constraints

Shachnai, Hadas

448

System on Programable Chip for Performance Estimation of Loom Machine  

E-print Network

System on programmable chip for the performance estimation of loom machine, which calculates the efficiency and meter count for weaved cloth automatically. Also it calculates the efficiency of loom machine. Previously the same was done using manual process which was not efficient. This article is intended for loom machines which are not modern.

Singh, Gurpreet; S, Surekha K; Pujari, S

2012-01-01

449

Fabrication, evaluation, and performance of machined metal grazing incidence telescopes  

Microsoft Academic Search

The fabrication, evaluation, and performance of machined grazing incidence metal optics for applications ranging from telescopes with imaging of minutes of arc to those with imaging in the less-than-10-arcsec range are reviewed. Issues considered in the fabrication process include the choice of machining substrate, the choice of machine tool, the choice of method for removing tool marks, and the choice

Stuart Bowyer; James Green

1988-01-01

450

Waterless Clothes-Cleaning Machine  

NASA Technical Reports Server (NTRS)

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.

Johnson, Glenn; Ganske, Shane

2013-01-01

451

Interactive Gumball Machine  

NSDL National Science Digital Library

In this activity, learners review the history of gumball machines and explore potential and kinetic energy, while working in teams to build a gumball slide. Teams then design and build their own interactive gumball machine.

2013-08-30

452

Infinite Time Turing Machines  

Microsoft Academic Search

Infinite time Turing machines extend the operation of ordinary Turing machines into transfinite ordinal time. By doing so, they provide a natural model of infinitary computability, a theoretical setting for the analysis of the power and limitations of supertask algorithms.

Joel David Hamkins

2002-01-01

453

LISP Machine Progress Report  

E-print Network

This informal paper introduces the LISP Machine, describes the goals and current status of the project, and explicates some of the key ideas. It covers the LISP machine implementation, LISP as a system language, ...

Bawden, Alan

1977-08-01

454

Stirling machine operating experience  

NASA Technical Reports Server (NTRS)

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.

Ross, Brad; Dudenhoefer, James E.

1991-01-01

455

Stirling machine operating experience  

NASA Astrophysics Data System (ADS)

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.

Ross, Brad A.; Dudenhoefer, James E.

456

Improving Energy Efficiency in CNC Machining  

NASA Astrophysics Data System (ADS)

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.

Pavanaskar, Sushrut S.

457

Internet Archive Wayback Machine  

NSDL National Science Digital Library

The Internet Archive is the "parent" site for two sites previously reviewed in the Scout Report, Election 2000 (see the July 13, 2001 Scout Report) and September11.archive.org (see the October 19, 2001 Scout Report). The Archive has been cataloging Webpages since its inception in 1996, and for their fifth anniversary has opened the archive to the public by launching their "Wayback Machine." To operate the "Machine," users type a URL into the search box, which will call up dated, archived pages of the site. The Internet Archive holds ten billion Webpages, making it the largest known database. Since announcing public access to the overall database, the site has experienced a great deal of traffic. They are in the process of adding servers, but users should be warned that, in the meantime, access may be tricky. The Internet Archive is a nonprofit, which has received funding from a number of sources including the Library of Congress and the National Science Foundation.

458

The Advantage of Machines  

NSDL National Science Digital Library

In this lesson, students learn about work as defined by physical science and see that work is made easier through the use of simple machines. Already encountering simple machines everyday, students will be learn about their widespread uses in improving everyday life. This lesson serves as the starting point for the Simple Machines Unit.

Integrated Teaching And Learning Program

459

Millikelvin Lab Machine Shop  

E-print Network

Millikelvin Lab OP105­112 Machine Shop OP132 Resistive Magnet Shop CICC Winding Area Transformers This building is home to the Millikelvin lab, the control room, the resistive magnet and machine shops, the CICC@magnet.fsu.edu (850) 644-4378 (850) 644-0534 2 MACHINE SHOP OP132 Vaughan Williams (A114*) williams

McQuade, D. Tyler

460

Talking Vending Machines  

E-print Network

're in the central Tokyo Station and you're thirsty so you go to the, you know, vending machine to buy a drink. Only this is not your average vending machine. Uh uh. This vending machine has opinions on what beverage you want. Sensors built into large touch panels...

Hacker, Randi

2011-02-02

461

Cable-Twisting Machine  

NASA Technical Reports Server (NTRS)

New cable-twisting machine is smaller and faster than many production units. Is useful mainly in production of short-run special cables. Already-twisted cable can be fed along axis of machine. Faster operation than typical industrial cable-twisting machines possible by using smaller spools of wire.

Kurnett, S.

1982-01-01

462

Find the Simple Machines  

NSDL National Science Digital Library

This is a web activity about simple machines. Learners will explore a lawn mower and identify six different simple machines which work together to help make our lives easier. This is an excellent activity for exploring how simple machines, and science in general, apply to learners' everyday lives.

Cosi

2000-01-01

463

Your Sewing Machine.  

ERIC Educational Resources Information Center

The programed instruction manual is designed to aid the student in learning the parts, uses, and operation of the sewing machine. Drawings of sewing machine parts are presented, and space is provided for the student's written responses. Following an introductory section identifying sewing machine parts, the manual deals with each part and its…

Peacock, Marion E.

464

What is Machine Learning? About the Course Example Machine Learning  

E-print Network

What is Machine Learning? About the Course Example Machine Learning DD2431 ¨Orjan Ekeberg Oct­Dec, 2007 What is Machine Learning? About the Course Example 1 What is Machine Learning? Definition A Hypothetical Project What is Machine Learning? About the Course Example 1 What is Machine Learning? Definition

Kjellström, Hedvig

465

What is Machine Learning? About the Course Example Machine Learning  

E-print Network

What is Machine Learning? About the Course Example Machine Learning DD2431 ¨Orjan Ekeberg Oct­Dec, 2007 #12;What is Machine Learning? About the Course Example 1 What is Machine Learning? Definition A Hypothetical Project #12;What is Machine Learning? About the Course Example 1 What is Machine Learning

Kjellström, Hedvig

466

What is Machine Learning? About the Course Example Machine Learning  

E-print Network

What is Machine Learning? About the Course Example Machine Learning DD2431 ¨Orjan Ekeberg Oct­Dec, 2008 #12;What is Machine Learning? About the Course Example 1 What is Machine Learning? Definition A Hypothetical Project #12;What is Machine Learning? About the Course Example 1 What is Machine Learning

Kjellström, Hedvig

467

What is Machine Learning? About the Course Example Machine Learning  

E-print Network

What is Machine Learning? About the Course Example Machine Learning DD2431 ¨Orjan Ekeberg Oct­Dec, 2008 What is Machine Learning? About the Course Example 1 What is Machine Learning? Definition A Hypothetical Project What is Machine Learning? About the Course Example 1 What is Machine Learning? Definition

Kjellström, Hedvig

468

Why Machine Learning and Games? Machine Learning in Video Games  

E-print Network

#12;Why Machine Learning and Games? Machine Learning in Video Games DrivatarsTM Reinforcement entertainment valueWhat is the best AI? #12;Why Machine Learning and Games? Machine Learning in Video Games;#12;Why Machine Learning and Games? Machine Learning in Video Games DrivatarsTM Reinforcement Learning

Hunt, Galen

469

Circular tests for HSM machine tools: Bore machining application  

E-print Network

operations lies in understanding the impact of machine tool behaviour on machining time and part qualityCircular tests for HSM machine tools: Bore machining application Abstract: Today's High-Speed Machining (HSM) machine tool combines productivity and part quality. The difficulty inherent in HSM

Paris-Sud XI, Université de

470

Primary Masters in Machine Learning  

E-print Network

Primary Masters in Machine Learning Student Handbook #12;#12;Page 1 Masters in Machine Learning:.......................................................................................8 Machine Learning Journal Club ..................................................................12 #12;Page 3 Introduction The field of machine learning is concerned with the question of how

471

Machining algebra for mapping volumes to machining operations for developing extensible generative CAPP  

Microsoft Academic Search

This paper presents geometric models for representing machining operations. The characteristic shapes produced by machining operations are represented in a uniform (canonical) form. The canonical representation is an algebraic expression that encodes the geometric shapes that can be produced by a process as a set of volumes resulting from two types of tool-workplace interactions. Each interaction is characterized by a

Arvind Shirur; Jami J. Shah; Kartheek Hirode

1998-01-01

472

Micro electro-discharge machining of ink jet nozzles: optimum selection of material and machining parameters  

Microsoft Academic Search

A comprehensive examination of ink jet nozzles manufactured by the micro electro-discharge machining (MEDM) process has been conducted as part of a study to develop an understanding of the effects of MEDM on the hole properties, the issuing jet directionality and stability and the subsequent ink jet printer performance. Ink jet orifices were machined into thin foils made of different

D. M. Allen; A. Lecheheb

1996-01-01

473

Imbalance rotating machine balancing  

NASA Astrophysics Data System (ADS)

Imbalance analysis is essential in the rotating machine. However, some problems still remain in the aspects of computational efficiency and accuracy. In the present paper, a new method was proposed for estimating the mass imbalance of a rotating shaft by using the vibration signals. This is a new method for the detection of a mass imbalance and its phase position. Based on the signal processing with FFT, an estimator was designed to detect the mass of imbalance. And an improved Lissajous diagram was also introduced with statistical analysis, which make it possible to compute the phase position of the mass imbalance efficiently and arranged at a certain location of the shaft. The proposed method was demonstrated and validated through several test examples.

Su, Hua; Choi, Han-Soo; Chong, Kil To

2005-12-01

474

Unified Universal Quantum Cloning Machine and Fidelities  

E-print Network

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.

Yi-Nan Wang; Han-Duo Shi; Zhao-Xi Xiong; Li Jing; Xi-Jun Ren; Liang-Zhu Mu; Heng Fan

2011-04-25

475

Unified universal quantum cloning machine and fidelities  

SciTech Connect

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.

Wang Yinan; Shi Handuo; Xiong Zhaoxi; Jing Li; Mu Liangzhu [School of Physics, Peking University, Beijing 100871 (China); Ren Xijun [School of Physics and Electronics, Henan University, Kaifeng 4750011 (China); Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2011-09-15

476

Experimental investigation on material migration phenomena in micro-EDM of reaction-bonded silicon carbide  

NASA Astrophysics Data System (ADS)

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.

Liew, Pay Jun; Yan, Jiwang; Kuriyagawa, Tsunemoto

2013-07-01

477

Environmental impact estimation of mold making process  

NASA Astrophysics Data System (ADS)

Increasing concern of environmental sustainability regarding depletion of natural resources and resulting negative environmental impact has triggered various movements to address these issues. Various regulations about product life cycle have been made and applied to industries. As a result, how to evaluate the environmental impact and how to improve current technologies has become an important issue to product developers. Molds and dies are very generally used manufacturing tools and indispensible parts to the production of many products. However, evaluating environmental impact in mold and die manufacturing is not well understood and not much accepted yet. The objective of this thesis is to provide an effective and straightforward way of environmental analysis for mold and die manufacturing practice. For this, current limitations of existing tools were identified. While conventional life cycle assessment tools provide a lot of life cycle inventories, reliable data is not sufficient for the mold and die manufacturer. Even with comprehensive data input, current LCA tools only provide another comprehensive result which is not directly applicable to problem solving. These issues are critical especially to the mold and die manufacturer with limited resource and time. This thesis addresses the issues based on understanding the needs of mold and die manufacturers. Computer aided manufacturing (CAM) is the most frequently used software tool and includes most manufacturing information including the process definition and sometimes geometric modeling. Another important usage of CAM software tools is problem identification by process simulation. Under the virtual environment, possible problems are detected and solved. Environmental impact can be handled in the same manner. To manufacture molds and dies with minimizing the associated environmental impact, possible environmental impact sources must be minimized before the execution in the virtual environment. Molds and dies are manufacturing intensive products and most of their environmental impact is generated by the energy consumption during the machining processes. Milling and EDM operations were selected as the most influential mold and die manufacturing processes. Process variability was found to be the key issue which must be addressed for reliable analysis. Acceleration and deceleration in the milling process and the dielectric contamination and resultant decrease of MRR in the EDM process were identified as main factors for the variability. Energy consumption of these two processes were analyzed and modeled including the variability. Experiments were carried out to validate and improve this model. Finally, this model is implemented as simulation software tools on the basis of CAM software (Esprit CAM(TM)). The CAM-based tool developed in this study can be more easily used in the mold and die manufacturing practice. Considering the variety of mold and die and their application, this tool would be just a small step to a long way to the environmentally benign mold and die manufacturing. However, with further research, the tool developed in this thesis will result in effective way to address environmentally benign mold and die manufacturing.

Kong, Daeyoung

478

Machinability of a Stainless Steel by Electrochemical Discharge Microdrilling  

SciTech Connect

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.

Coteata, Margareta; Pop, Nicolae; Slatineanu, Laurentiu ['Gheorghe Asachi' Technical University of Iasi, Department of Machine Manufacturing Technology, Blvd. D Mangeron 59A, 700050 Iasi (Romania); Schulze, Hans-Peter [Otto-von-Guericke-University Magdeburg, Institute of Fundamental Electrical Engineering and EMC Universitaetsplatz 2, D-39106 Magdeburg (Germany); Besliu, Irina [University 'Stefan cel Mare' of Suceava, Department of Technologies and Management, Str. Universitatii, 13, 720 229 Suceava (Romania)

2011-05-04

479

Effect of electric discharge machining on the fatigue life of Inconel 718  

NASA Technical Reports Server (NTRS)

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.

Jeelani, S.; Collins, M. R.

1988-01-01

480

Perspex machine: VII. The universal perspex machine  

NASA Astrophysics Data System (ADS)

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.

Anderson, James A. D. W.

2006-01-01

481

2006-1990: ENGAGING UNDERGRADUATE STUDENTS IN MACHINE LEARNING RESEARCH: PROGRESS, EXPERIENCES AND ACHIEVEMENTS  

E-print Network

2006-1990: ENGAGING UNDERGRADUATE STUDENTS IN MACHINE LEARNING RESEARCH: PROGRESS, EXPERIENCES Processing and Recognition, Blind Source Separation, , Image Processing, Natural Language Understanding, Human Machine Interface. He holds a number of patents in speech recognition area. Philip Chan, Florida

Anagnostopoulos, Georgios C.

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Characterizing forest canopy structure with lidar composite metrics and machine learning  

E-print Network

Characterizing forest canopy structure with lidar composite metrics and machine learning Kaiguang Laser scanner Canopy Biomass Carbon Machine learning Gaussian process Support vector machine Forest fuel scanners through the combined use of lidar composite metrics and machine learning models. Our so