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Sample records for machine simulations loco

  1. Matlab Based LOCO

    Energy Technology Data Exchange (ETDEWEB)

    Portmann, Greg; /LBL, Berkeley; Safranek, James; Huang, Xiaobiao; /SLAC

    2011-10-18

    The LOCO algorithm has been used by many accelerators around the world. Although the uses for LOCO vary, the most common use has been to find calibration errors and correct the optics functions. The light source community in particular has made extensive use of the LOCO algorithms to tightly control the beta function and coupling. Maintaining high quality beam parameters requires constant attention so a relatively large effort was put into software development for the LOCO application. The LOCO code was originally written in FORTRAN. This code worked fine but it was somewhat awkward to use. For instance, the FORTRAN code itself did not calculate the model response matrix. It required a separate modeling code such as MAD to calculate the model matrix then one manually loads the data into the LOCO code. As the number of people interested in LOCO grew, it required making it easier to use. The decision to port LOCO to Matlab was relatively easy. It's best to use a matrix programming language with good graphics capability; Matlab was also being used for high level machine control; and the accelerator modeling code AT, [5], was already developed for Matlab. Since LOCO requires collecting and processing a relative large amount of data, it is very helpful to have the LOCO code compatible with the high level machine control, [3]. A number of new features were added while porting the code from FORTRAN and new methods continue to evolve, [7][9]. Although Matlab LOCO was written with AT as the underlying tracking code, a mechanism to connect to other modeling codes has been provided.

  2. Is there LOCOS after LOCOS?

    Science.gov (United States)

    Deleonibus, S.

    1997-07-01

    Decreasing the field oxide thickness, increasing the temperature or oxidation pressure in a LOCOS type isolation improves field oxide thinning. Under the above regimes, the bird's beak growth results from a reaction-limited mechanism during the linear part of the oxidation process. The latter property is of major importance for the future shrink of LOCOS isolation towards sub-0.1 μm CMOS designs. Market pressure, because of the strong demand for low-voltage and low-power ULSI devices, is defining the framework. Matching the trend in depth-of-focus reduction in lithography tools and limiting process complexity will have to be weighed constantly. The reduction of isolation dimension losses to zero is not as urgent as it used to be. Shallow trench isolation has not come to maturity because of the technically difficult and economically practicable trade-off to be found between planarization and device leakage. Refilling and planarization process standards have not yet been established despite the major progress made in chemical mechanical polishing. The contradiction betwen the planarization issue and the need for an abrupt step at the isolation/active-area edge in order to avoid subthreshold leakage of the MOS active sidewalls still has to be solved. After a brief historical review, we point out and reconsider the main advantages and drawbacks of LOCOS type and shallow trench isolation processes. Within that framework, the impact of isolation design rules on device integration density and isolation performance is reviewed and commented on.

  3. Simulating Turing machines on Maurer machines

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2008-01-01

    In a previous paper, we used Maurer machines to model and analyse micro-architectures. In the current paper, we investigate the connections between Turing machines and Maurer machines with the purpose to gain an insight into computability issues relating to Maurer machines. We introduce ways to

  4. Machine Learning and Cosmological Simulations

    Science.gov (United States)

    Kamdar, Harshil; Turk, Matthew; Brunner, Robert

    2016-01-01

    We explore the application of machine learning (ML) to the problem of galaxy formation and evolution in a hierarchical universe. Our motivations are two-fold: (1) presenting a new, promising technique to study galaxy formation, and (2) quantitatively evaluating the extent of the influence of dark matter halo properties on small-scale structure formation. For our analyses, we use both semi-analytical models (Millennium simulation) and N-body + hydrodynamical simulations (Illustris simulation). The ML algorithms are trained on important dark matter halo properties (inputs) and galaxy properties (outputs). The trained models are able to robustly predict the gas mass, stellar mass, black hole mass, star formation rate, $g-r$ color, and stellar metallicity. Moreover, the ML simulated galaxies obey fundamental observational constraints implying that the population of ML predicted galaxies is physically and statistically robust. Next, ML algorithms are trained on an N-body + hydrodynamical simulation and applied to an N-body only simulation (Dark Sky simulation, Illustris Dark), populating this new simulation with galaxies. We can examine how structure formation changes with different cosmological parameters and are able to mimic a full-blown hydrodynamical simulation in a computation time that is orders of magnitude smaller. We find that the set of ML simulated galaxies in Dark Sky obey the same observational constraints, further solidifying ML's place as an intriguing and promising technique in future galaxy formation studies and rapid mock galaxy catalog creation.

  5. On the numerical simulation of machining processes

    OpenAIRE

    Vaz Jr.,M.

    2000-01-01

    Numerical simulation of machining processes can be traced back to the early seventies when finite element models for continuous chip formation were proposed. The advent of fast computers and development of new techniques to model large plastic deformations have favoured machining simulation. Relevant aspects of finite element simulation of machining processes are discussed in this paper, such as solution methods, material models, thermo-mechanical coupling, friction models, chip separation an...

  6. In Loco Parentis Indulgentis?

    Science.gov (United States)

    Pitts, James H.

    1980-01-01

    Examines significant aspects of student personnel work vis a vis student development. Reveals that "in loco parentis" has been a manifestation of a more overarching philosophical belief that colleges should foster the development of the whole student. (Author)

  7. In Loco Parentis Revisited?

    Science.gov (United States)

    Morrill, Richard L.; And Others

    1986-01-01

    Two perspectives are presented on some of the questions raised as the doctrine of the college 'in loco parentis' re-emerges as a campus issue, including student, parent, and institutional expectations. (MSE)

  8. Determination of Induction Machine Parameters by Simulation

    OpenAIRE

    Dr. E.A. Anazia; Engr. Samson Ugochukwu; Dr. J. C. Onuegbu; Engr. Onyedikachi S.N

    2016-01-01

    A 38.1 Watt fractional horse power induction laboratory test motor model was created using MotorSolve 5.2; an electrical machine design application. Initial machine parameters such as voltage, speed, and main dimensions were selected and fed into the application and simulations ran. The simulated results were presented and analyzed. Unlike other induction machine parameter identification process, this method is simple, flexible and accurate since it does not involve rigorous mathe...

  9. COMPUTER SIMULATION OF A STIRLING REFRIGERATING MACHINE

    Directory of Open Access Journals (Sweden)

    V.V. Trandafilov

    2015-10-01

    Full Text Available In present numerical research, the mathematical model for precise performance simulation and detailed behavior of Stirling refrigerating machine is considered. The mathematical model for alpha Stirling refrigerating machine with helium as the working fluid will be useful in optimization of these machines mechanical design. Complete non-linear mathematical model of the machine, including thermodynamics of helium, and heat transfer from the walls, as well as heat transfer and gas resistance in the regenerator is developed. Non-dimensional groups are derived, and the mathematical model is numerically solved. Important design parameters are varied and their effect on Stirling refrigerating machine performance determined. The simulation results of Stirling refrigerating machine which include heat transfer and coefficient of performance are presented.

  10. SIMULATION OF MULTI-SUPPORT MACHINE VIBRATIONS

    Directory of Open Access Journals (Sweden)

    N. N. Hurski

    2009-01-01

    Full Text Available The paper considers problems pertaining to simulation of multi-support machine vibrations by means of  ADMOS programming product. A mathematical model of the multi-support machine is presented and its main geometric and physical and mechanical parameters are given in the paper. The paper reveals analysis results of the vibration processes and observes variables in time and frequency areas. The investigations have made it possible to obtain amplitude and frequency and statistical characteristics  of  the machine mass centre acceleration during its motion along various types of roads

  11. Modelling and simulation of multitechnological machine systems

    Energy Technology Data Exchange (ETDEWEB)

    Holopainen, T. (ed.) [VTT Manufacturing Technology, Espoo (Finland)

    2001-07-01

    The Smart Machines and Systems 2010 (SMART) technology programme 1997-2000 aimed at supporting the machine and electromechanical industries in incorporating the modern technology into their products and processes. The public research projects in this programme were planned to accumulate the latest research results and transfer them for the benefit of industrial product development. The major research topic in the SMART programme was called Modelling and Simulation of Multitechnological Mechatronic Systems. The behaviour of modern machine systems and subsystems addresses many different types of physical phenomena and their mutual interactions: mechanical behaviour of structures, electromagnetic effects, hydraulics, vibrations and acoustics etc. together with associated control systems and software. The actual research was carried out in three separate projects called Modelling and Simulation of Mechtronic Machine Systems for Product Development and Condition Monitoring Purposes (MASI), Virtual Testing of Hydraulically Driven Machines (HYSI), and Control of Low Frequency Vibration of a Mobile Machine (AKSUS). This publication contains the papers presented at the final seminar of these three research projects, held on November 30th at Otaniemi Espoo. (orig.)

  12. Development of Virtual Simulation System for Remote Collaborative Surface Machining

    Institute of Scientific and Technical Information of China (English)

    R.S.Lee; Y.S.Lin; Y.C.Kao; C. H. She

    2006-01-01

    Most researches about virtual machine tool are emphasized on simulations of machine motion and machining process for single machine. In this paper, a virtual simulation system for remote collaborative surface machining is developed. The motion command of machine tool is generated by an interpolator, which can derive synchronized motion commands according to feedrate. Thus, the system can estimate the machining time. For universal assembly of five-axis virtual machine tool, it is based on the D-H notation representation and machining constraints consideration. The remote collaborative virtual manufacturing system based on the CORBA technology is proposed in this paper. It demonstrated that the developed virtual machine tool can be used to verify and simulate the machining process for the collaboration of the surface design and manufacturing team.

  13. Machine Learning and Cosmological Simulations II: Hydrodynamical Simulations

    CERN Document Server

    Kamdar, Harshil M; Brunner, Robert J

    2015-01-01

    We extend a machine learning (ML) framework presented previously to model galaxy formation and evolution in a hierarchical universe using N-body + hydrodynamical simulations. In this work, we show that ML is a promising technique to study galaxy formation in the backdrop of a hydrodynamical simulation. We use the Illustris Simulation to train and test various sophisticated machine learning algorithms. By using only essential dark matter halo physical properties and no merger history, our model predicts the gas mass, stellar mass, black hole mass, star formation rate, $g-r$ color, and stellar metallicity fairly robustly. Our results provide a unique and powerful phenomenological framework to explore the galaxy-halo connection that is built upon a solid hydrodynamical simulation. The promising reproduction of the listed galaxy properties demonstrably place ML as a promising and a significantly more computationally efficient tool to study small-scale structure formation. We find that ML mimics a full-blown hydro...

  14. Loco signaling pathway in longevity.

    Science.gov (United States)

    Lin, Yuh-Ru; Parikh, Hardik; Park, Yongkyu

    2011-05-01

    Despite the various roles of regulator of G protein signaling (RGS) protein in the G protein signaling pathway that have been defined, the function of RGS has not been characterized in longevity signaling pathways. We found that reduced expression of Loco, a Drosophila RGS protein, resulted in a longer lifespan of flies with stronger resistance to stress, higher MnSOD activity and increased fat content. In contrast, overexpression of the loco gene shortened the fly lifespan significantly, lowered stress resistance and reduced fat content, also indicating that the RGS domain containing GTPase-activating protein (GAP) activity is related to the regulation of longevity. Interestingly, expressional changes of yeast RGS2 and rat RGS14, homologs to the fly Loco, also affected oxidative stress resistance and longevity in the respective species. It is known that Loco inactivates inhibitory Gαi•GTP protein to reduce activity of adenylate cyclase (AC) and RGS14 interacts with activated H-Ras and Raf-1 kinases, which subsequently inhibits ERK phosphorylation. We propose that Loco/RGS14 protein may regulate stress resistance and longevity as an activator in AC-cAMP-PKA pathway and/or as a molecular scaffold that sequesters active Ras and Raf from Ras•GTP-Raf-MEK-ERK signaling pathway. Consistently, our data showed that downregulation of Loco significantly diminishes cAMP amounts and increases p-ERK levels with higher resistance to the oxidative stress.

  15. SIMULATED MACHINES FOR SOIL TREATMENT FOR FELLING AND SLASH AREAS

    Directory of Open Access Journals (Sweden)

    Alekseev A. E.

    2013-10-01

    Full Text Available The article presents the results of a simulation of functioning machines for tillage in AutoCAD Mechanical environment, the algorithm of machine work and the results of numerical experiments on the developed model

  16. Simulation and Optimization of Turning-Milling Complex Machining

    Directory of Open Access Journals (Sweden)

    Shihong Guo

    2013-05-01

    Full Text Available In this study, the turning-milling complex processing simulation platform is established based on the simulation and optimization platform of VERICUT NC machining, with WFL M65 turning-milling complex machining center as the research object; taking barrel body parts as an example, the simulation machining and related process issues checking in machining process is made and the analysis and optimization of effect factors is made for processing efficiency. The application indicates that: the research results effectively realize the simulation of the turning-milling complex machining process and the correctness verification and process optimization of the NC machining program, improve the processing efficiency and the processing quality, well improve the application level of enterprise turning-milling complex machining center, promote the development of the turning-milling complex machining technology.

  17. Changes in the loco-regional cerebral blood flow (r.C.B.F.) during a simulation of weightlessness

    Science.gov (United States)

    Guell, A.; Dupui, Ph.; Barrere, M.; Fanjaud, G.; Bes, A.; Kotowskaia, A.

    Experiments of prolonged bedrest in antiorthostatic position are conducted in order to simulate cardio-circulatory modifications observed in weightlessness. Until now, no studies of r.C.B.F. have been effected in these conditions. Six young, healthy volunteers (average age 23.8) were placed in strict bedrest and in antiorthostatic position -4° for 7 days. The r.C.B.F. measurements were studied by 133Xe inhalation method using a 32 detectors system. Studies were made first in basal conditions, then between the 6th and 12th hr, and finally between the 72nd and the 78th hr after the beginning of the experiment. Three of the subjects received 0.450 mg of Clonidine daily during the experiment. In the subjects having taken no Clonidine, we observed a constant increase in r.C.B.F. (12, 17 and 16% respectively) in the first 12 hr; at the 72nd hour, all values had returned to basal state. This findings agrees with the well known notion of a rapid correction of hemodynamic disturbances observed in the first days of weightlessness. In the subjects treated with Clonidine, the increase of r.C.B.F. did not occur. Several mechanicsms of action are possible; the Clonidine affecting either the heart by inhibiting volemic atrial receptors, or the brain by direct vasoconstriction.

  18. Perspective: Machine learning potentials for atomistic simulations

    Science.gov (United States)

    Behler, Jörg

    2016-11-01

    Nowadays, computer simulations have become a standard tool in essentially all fields of chemistry, condensed matter physics, and materials science. In order to keep up with state-of-the-art experiments and the ever growing complexity of the investigated problems, there is a constantly increasing need for simulations of more realistic, i.e., larger, model systems with improved accuracy. In many cases, the availability of sufficiently efficient interatomic potentials providing reliable energies and forces has become a serious bottleneck for performing these simulations. To address this problem, currently a paradigm change is taking place in the development of interatomic potentials. Since the early days of computer simulations simplified potentials have been derived using physical approximations whenever the direct application of electronic structure methods has been too demanding. Recent advances in machine learning (ML) now offer an alternative approach for the representation of potential-energy surfaces by fitting large data sets from electronic structure calculations. In this perspective, the central ideas underlying these ML potentials, solved problems and remaining challenges are reviewed along with a discussion of their current applicability and limitations.

  19. The Lunar Occultation Observer (LOCO) mission concept

    Science.gov (United States)

    Miller, Richard S.

    2007-09-01

    The hard X-ray sky has tremendous potential for future discoveries and is one of the last electromagnetic regimes without a sensitive all-sky survey. A new approach to such a survey is to utilize the Moon as an occulting disk. The Lunar Occultation Observer (LOCO) mission concept, based on this Lunar Occultation Technique (LOT) and incorporating advanced inorganic scintillators as a detection medium, represents a sensitive and cost effective option for NASA's Beyond Einstein Black Hole Finder Probe or a future Explorer-class mission. We present the motivating factors for the LOT, outline developmental details and simulation results, as well as give preliminary estimates for source detection sensitivity.

  20. El loco y el idiota.

    OpenAIRE

    Alfredo Fierro Bardají

    1982-01-01

    El loco y el idiota -denominados así, según el uso cotidiano y vulgar, inmisericordemente despectivo -sin duda alguna son las dos figuras paradigmáticas de enajenación de la razón, el uno por desarreglo, el otro por defecto. El loco es el trastornado en su razón, el que se ha hecho un desbarajuste con un poder anímico esencialmente orientado a crear orden, a producir ideas claras y distintas. El idiota es el deficiente en su razón, el que participa de ella en medida tan escasa que se queda en...

  1. The New In Loco Parentis.

    Science.gov (United States)

    Thomas, Nancy L.

    1991-01-01

    Traditionally, colleges have had right to act in place of student's parents and duty to protect his safety, morals, and welfare. Dramatic changes in this approach occurred after World War II including rejection of the loco parentis role by courts, but trend is away from freedom and flexibility of 1960s as illustrated by policy changes at Boston…

  2. Is "In Loco Parentis" Dead?

    Science.gov (United States)

    Zirkel, Perry A.; Reichner, Henry F.

    1987-01-01

    The concept "in loco parentis" is discussed in relation to its historical place in education and its current status. The doctrine has expanded from its original idea of "restraint and correction" to figure significantly in court cases involving corporal punishment, student searches, school rules, correlative duties, and…

  3. Machine learning and cosmological simulations - II. Hydrodynamical simulations

    Science.gov (United States)

    Kamdar, Harshil M.; Turk, Matthew J.; Brunner, Robert J.

    2016-04-01

    We extend a machine learning (ML) framework presented previously to model galaxy formation and evolution in a hierarchical universe using N-body + hydrodynamical simulations. In this work, we show that ML is a promising technique to study galaxy formation in the backdrop of a hydrodynamical simulation. We use the Illustris simulation to train and test various sophisticated ML algorithms. By using only essential dark matter halo physical properties and no merger history, our model predicts the gas mass, stellar mass, black hole mass, star formation rate, g - r colour, and stellar metallicity fairly robustly. Our results provide a unique and powerful phenomenological framework to explore the galaxy-halo connection that is built upon a solid hydrodynamical simulation. The promising reproduction of the listed galaxy properties demonstrably place ML as a promising and a significantly more computationally efficient tool to study small-scale structure formation. We find that ML mimics a full-blown hydrodynamical simulation surprisingly well in a computation time of mere minutes. The population of galaxies simulated by ML, while not numerically identical to Illustris, is statistically robust and physically consistent with Illustris galaxies and follows the same fundamental observational constraints. ML offers an intriguing and promising technique to create quick mock galaxy catalogues in the future.

  4. Study on Simulation of Machining Errors Caused by Cutting Force

    Institute of Scientific and Technical Information of China (English)

    SHAO Xiaodong; ZHANG Liu; LIN Zhaoxu

    2006-01-01

    Machining errors caused by cutting force are studied in this paper, and an algorithm to simulate errors is putted forward. In the method, continuous machining process is separated into many machining moments. The deformation of work-piece and cutter at every moment is calculated by finite element method. The machined work-piece is gained by Boolean operation between deformed work-piece and cutter. By analyzing data of final work-piece, machining errors are predicted. The method is proved true by experiment.

  5. El loco y el idiota.

    Directory of Open Access Journals (Sweden)

    Alfredo Fierro Bardají

    1982-01-01

    Full Text Available El loco y el idiota -denominados así, según el uso cotidiano y vulgar, inmisericordemente despectivo -sin duda alguna son las dos figuras paradigmáticas de enajenación de la razón, el uno por desarreglo, el otro por defecto. El loco es el trastornado en su razón, el que se ha hecho un desbarajuste con un poder anímico esencialmente orientado a crear orden, a producir ideas claras y distintas. El idiota es el deficiente en su razón, el que participa de ella en medida tan escasa que se queda en un grado subhumano, a la altura de los brutos animales. La razón -una cierta determinación ideológica y práctica de la razón -crea al idiota y al loco como necesarios antagonistas para poder desarrollar su aventura histórica. Relegados a los rincones de la escena donde la razón occidental moderna despliega sus hazañas, en ningún modo son personajes secundarios de la historia. En su penumbra y su mutismo revelan sobre la razón secretos que ésta, en toda su cartesiana autoconciencia, nunca quiso ni pudo vislumbrar.

  6. Motion Simulation Analysis of Rail Weld CNC Fine Milling Machine

    Science.gov (United States)

    Mao, Huajie; Shu, Min; Li, Chao; Zhang, Baojun

    CNC fine milling machine is a new advanced equipment of rail weld precision machining with high precision, high efficiency, low environmental pollution and other technical advantages. The motion performance of this machine directly affects its machining accuracy and stability, which makes it an important consideration for its design. Based on the design drawings, this article completed 3D modeling of 60mm/kg rail weld CNC fine milling machine by using Solidworks. After that, the geometry was imported into Adams to finish the motion simulation analysis. The displacement, velocity, angular velocity and some other kinematical parameters curves of the main components were obtained in the post-processing and these are the scientific basis for the design and development for this machine.

  7. Simulation of machine interference in randomly changing environments

    Directory of Open Access Journals (Sweden)

    Sztrik J.

    2002-01-01

    Full Text Available The simulation tool lcpSim can be used to investigate special level crossing problems of queuing systems of type HYPOk / HYPOr / 1 // n embedded in different Markovian environments (recently referred to as Markov modulated ones. Our observed system consists of n heterogeneous machines (requests and a server that 'repairs' the broken machines according to the most commonly used service disciplines, such as FIFO, LIFO, PPS, HOL, Preemptive Priorities (Resume, Repeat, Transfer, Polling, Nearest. We specify a maximum number of stopped machines for an operating system and our aim is to give the main steady-state performance measures of the system, such as, server utilization, machine utilization, mean waiting times, mean response times, the probability of an operating system and the mean operating time of the system. These values can be calculated by lcpSim level crossing problem Simulation package for different random environment types and service disciplines.

  8. Three-dimensional direct particle simulation on the Connection Machine

    Science.gov (United States)

    Dagum, Leonardo

    1991-01-01

    This paper presents the algorithms necessary for an efficient data parallel implementation of a 3D particle simulation. In particular, a general master/slave algorithm and a fast sorting algorithm are described and the use of these algorithms in a particle simulation is outlined. A particle simulation using these algorithms has been implemented on a 32768 processor Connection Machine that is capable of simulating over 30 million particles at an average rate of 2.4-microsec/particle/step. Results are presented from the simulation of flow over an Aeroassisted Flight Experiment geometry at 100 km altitude.

  9. An advanced machining simulation environment employing workpiece structural analysis

    Directory of Open Access Journals (Sweden)

    A.A. Becker

    2006-04-01

    Full Text Available Purpose: The study aims to reduce the surface dimensional error due to the part deflection during the machining of thin wall structures, thus, reduce machining costs and lead times by producing “right first time” components.Design/methodology/approach: The proposed simulation environment involves a data model, an analytical force prediction model, a material removal model and an FE analysis commercial software package. It focuses on the development of the simulation environment with a multi-level machining error compensation approach.Findings: The developed simulation environment can predict and reduce the form error, which is a limitation of the existing approaches.Research limitations/implications: The energy consumption, temperature change and residual stress are not studied in this research.Practical implications: The developed method provides a platform to deliver new functionality for machining process simulation. The convergence of the proposed integrated system can be achieved quickly after only a few iterations, which makes the methodology reliable and efficient.Originality/value: The study offers an opportunity to satisfy tight tolerances, eliminate hand-finishing processes and assure part-to-part accuracy at the right first time, which is a limitation of previous approaches.

  10. Decentralized real-time simulation of forest machines

    Science.gov (United States)

    Freund, Eckhard; Adam, Frank; Hoffmann, Katharina; Rossmann, Juergen; Kraemer, Michael; Schluse, Michael

    2000-10-01

    To develop realistic forest machine simulators is a demanding task. A useful simulator has to provide a close- to-reality simulation of the forest environment as well as the simulation of the physics of the vehicle. Customers demand a highly realistic three dimensional forestry landscape and the realistic simulation of the complex motion of the vehicle even in rough terrain in order to be able to use the simulator for operator training under close-to- reality conditions. The realistic simulation of the vehicle, especially with the driver's seat mounted on a motion platform, greatly improves the effect of immersion into the virtual reality of a simulated forest and the achievable level of education of the driver. Thus, the connection of the real control devices of forest machines to the simulation system has to be supported, i.e. the real control devices like the joysticks or the board computer system to control the crane, the aggregate etc. Beyond, the fusion of the board computer system and the simulation system is realized by means of sensors, i.e. digital and analog signals. The decentralized system structure allows several virtual reality systems to evaluate and visualize the information of the control devices and the sensors. So, while the driver is practicing, the instructor can immerse into the same virtual forest to monitor the session from his own viewpoint. In this paper, we are describing the realized structure as well as the necessary software and hardware components and application experiences.

  11. Materiality of a simulation: Scratch reading machine, 1931

    Directory of Open Access Journals (Sweden)

    Craig Saper

    2009-12-01

    Full Text Available Using Bob Brown's reading machine and the prepared texts for his machine, called readies, both designed in 1930, as an example of scratch turntablist techniques, suggests an alternative to narrow definitions of literacy and new ways to appreciate the history of scratch techniques. Brown's machine resembles the turntablist’s ability to rapidly shift reading (its direction, speed, and repetition rather than slowly flipping the pages of a book. Punctuation marks, in the readies, become visual analogies. For movement we see em-dashes (— that also, by definition, indicate that the sentence was interrupted or cut short. The old uses of punctuation, such as employment of periods to mark the end of a sentence, disappear. The result looks like a script for a turntablist’s performance, and dj Herc starts to sound like a reading teacher. An online simulation of Brown's machine, http://www.readies.org, reproduce, or approximate, the motion, scratch, jerking, flickering, and visual effects produced or illuminated with the machine. Those supplemental aspects of reading are always already part of reading. The supplement (movement, visuality, mechanicity to traditional notions of literacy usually remain part of an implicate process. The reading machine and scratch techniques are not simply a new conduit for the same supposedly natural process. The scratch reading highlights what Jacques Derrida calls the "virtual multimedia" (of reading print on paper. The increasing prevalence, even omnipresent and [to some critics] epidemic, use of text(ing machines, something outside or beside traditional literacy, the scratch-meaning becomes foregrounded. Brown's machine puts the natural process of reading under erasure or scratch (simply by adjusting the speed, direction, and layout. dj Herc did the same for music.

  12. Simulation of induced radioactivity for Heavy Ion Medical Machine

    CERN Document Server

    Jun-Kui, Xu; Wu-Yuan, Li; Wang, Mao; Jia-Wen, Xia; Xi-Meng, Chen; Wei-Wei, Yan; Chong, Xu

    2013-01-01

    For radiation protection and environmental impact assessment purpose, the radioactivity induced by carbon ion of Heavy Ion Medical Machine (HIMM) was studied. Radionuclides in accelerator component, cooling water and air at target area which are induced from primary beam and secondary particles are simulated by FLUKA Monte Carlo code. It is found that radioactivity in cooling water and air is not very important at the required beam intensity and energy which is needed for treatment, radionuclides in accelerator component may cause some problem for maintenance work, suitable cooling time is needed after the machine are shut down.

  13. Accelerated Monte Carlo simulations with restricted Boltzmann machines

    Science.gov (United States)

    Huang, Li; Wang, Lei

    2017-01-01

    Despite their exceptional flexibility and popularity, Monte Carlo methods often suffer from slow mixing times for challenging statistical physics problems. We present a general strategy to overcome this difficulty by adopting ideas and techniques from the machine learning community. We fit the unnormalized probability of the physical model to a feed-forward neural network and reinterpret the architecture as a restricted Boltzmann machine. Then, exploiting its feature detection ability, we utilize the restricted Boltzmann machine to propose efficient Monte Carlo updates to speed up the simulation of the original physical system. We implement these ideas for the Falicov-Kimball model and demonstrate an improved acceptance ratio and autocorrelation time near the phase transition point.

  14. Accelerate Monte Carlo Simulations with Restricted Boltzmann Machines

    CERN Document Server

    Huang, Li

    2016-01-01

    Despite their exceptional flexibility and popularity, the Monte Carlo methods often suffer from slow mixing times for challenging statistical physics problems. We present a general strategy to overcome this difficulty by adopting ideas and techniques from the machine learning community. We fit the unnormalized probability of the physical model to a feedforward neural network and reinterpret the architecture as a restricted Boltzmann machine. Then, exploiting its feature detection ability, we utilize the restricted Boltzmann machine for efficient Monte Carlo updates and to speed up the simulation of the original physical system. We implement these ideas for the Falicov-Kimball model and demonstrate improved acceptance ratio and autocorrelation time near the phase transition point.

  15. Waveform interative techniques for device transient simulation on parallel machines

    Energy Technology Data Exchange (ETDEWEB)

    Lumsdaine, A. [Univ. of Notre Dame, IN (United States); Reichelt, M.W. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1993-12-31

    In this paper we describe our experiences with parallel implementations of several different waveform algorithms for performing transient simulation of semiconductor devices. Because of their inherent computation and communication structure, waveform methods are well suited to MIMD-type parallel machines having a high communication latency - such as a cluster of workstations. Experimental results using pWORDS, a parallel waveform-based device transient simulation program, in conjunction with PVM running on a cluster of eight workstations demonstrate that parallel waveform techniques are an efficient and faster alternative to standard simulation algorithms.

  16. Physics-Based Haptic Simulation of Bone Machining.

    Science.gov (United States)

    Arbabtafti, M; Moghaddam, M; Nahvi, A; Mahvash, M; Richardson, B; Shirinzadeh, B

    2011-01-01

    We present a physics-based training simulator for bone machining. Based on experimental studies, the energy required to remove a unit volume of bone is a constant for every particular bone material. We use this physical principle to obtain the forces required to remove bone material with a milling tool rotating at high speed. The rotating blades of the tool are modeled as a set of small cutting elements. The force of interaction between a cutting element and bone is calculated from the energy required to remove a bone chip with an estimated thickness and known material stiffness. The total force acting on the cutter at a particular instant is obtained by integrating the differential forces over all cutting elements engaged. A voxel representation is used to represent the virtual bone and removed chips for calculating forces of machining. We use voxels that carry bone material properties to represent the volumetric haptic body and to apply underlying physical changes during machining. Experimental results of machining samples of a real bone confirm the force model. A real-time haptic implementation of the method in a dental training simulator is described.

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

    Science.gov (United States)

    Wang, Sheng Ping; Padmanaban, Shivakumar

    2004-06-01

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

  18. Simulation Modeling and Analysis of Operator-Machine Ratio

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on a simulation model of a semiconductor manufacturer, operator-machine ratio (OMR) analysis is made using work study and time study. Through sensitivity analysis, it is found that labor utilization decreases with the increase of lot size.Meanwhile, it is able to identify that the OMR for this company should be improved from 1∶3 to 1∶5. An application result shows that the proposed model can effectively improve the OMR by 33%.

  19. Machine Learning and Cosmological Simulations I: Semi-Analytical Models

    OpenAIRE

    Kamdar, Harshil M.; Turk, Matthew J.; Brunner, Robert J.

    2015-01-01

    We present a new exploratory framework to model galaxy formation and evolution in a hierarchical universe by using machine learning (ML). Our motivations are two-fold: (1) presenting a new, promising technique to study galaxy formation, and (2) quantitatively analyzing the extent of the influence of dark matter halo properties on galaxies in the backdrop of semi-analytical models (SAMs). We use the influential Millennium Simulation and the corresponding Munich SAM to train and test various so...

  20. Simulation Process Analysis of Rubber Shock Absorber for Machine Tool

    Directory of Open Access Journals (Sweden)

    Chai Rong Xia

    2016-01-01

    Full Text Available The simulation on rubber shock absorber of machine tool was studied. The simple material model of rubber was obtained by through the finite element analysis software ABAQUS. The compression speed and the hardness of rubber material were considered to obtain the deformation law of rubber shock absorber. The location of fatigue were confirmed from the simulation results. The results shown that the fatigue position is distributed in the corner of shock absorber. The degree of deformation is increased with increasing of compress speed, and the hardness of rubber material is proportional to deformation.

  1. A novel approach in automatic estimation of rats' loco-motor activity

    Science.gov (United States)

    Anishchenko, Lesya N.; Ivashov, Sergey I.; Vasiliev, Igor A.

    2014-05-01

    The paper contains feasibility study of a method for bioradar monitoring of small laboratory animals loco-motor activity improved by using a corner reflector. It presents results of mathematical simulation of bioradar signal reflection from the animal with the help of finite-difference time-domain method. It was proved both by theoretical and experimental results that a corner reflector usage during monitoring of small laboratory animals loco-motor activity improved the effectiveness of the method by reducing the dependency of the power flux density level from the distance between antennas block and the object.

  2. Amp: A modular approach to machine learning in atomistic simulations

    Science.gov (United States)

    Khorshidi, Alireza; Peterson, Andrew A.

    2016-10-01

    Electronic structure calculations, such as those employing Kohn-Sham density functional theory or ab initio wavefunction theories, have allowed for atomistic-level understandings of a wide variety of phenomena and properties of matter at small scales. However, the computational cost of electronic structure methods drastically increases with length and time scales, which makes these methods difficult for long time-scale molecular dynamics simulations or large-sized systems. Machine-learning techniques can provide accurate potentials that can match the quality of electronic structure calculations, provided sufficient training data. These potentials can then be used to rapidly simulate large and long time-scale phenomena at similar quality to the parent electronic structure approach. Machine-learning potentials usually take a bias-free mathematical form and can be readily developed for a wide variety of systems. Electronic structure calculations have favorable properties-namely that they are noiseless and targeted training data can be produced on-demand-that make them particularly well-suited for machine learning. This paper discusses our modular approach to atomistic machine learning through the development of the open-source Atomistic Machine-learning Package (Amp), which allows for representations of both the total and atom-centered potential energy surface, in both periodic and non-periodic systems. Potentials developed through the atom-centered approach are simultaneously applicable for systems with various sizes. Interpolation can be enhanced by introducing custom descriptors of the local environment. We demonstrate this in the current work for Gaussian-type, bispectrum, and Zernike-type descriptors. Amp has an intuitive and modular structure with an interface through the python scripting language yet has parallelizable fortran components for demanding tasks; it is designed to integrate closely with the widely used Atomic Simulation Environment (ASE), which

  3. Data Simulation in Machine Olfaction with the R Package Chemosensors

    Science.gov (United States)

    Ziyatdinov, Andrey; Perera-Lluna, Alexandre

    2014-01-01

    In machine olfaction, the design of applications based on gas sensor arrays is highly dependent on the robustness of the signal and data processing algorithms. While the practice of testing the algorithms on public benchmarks is not common in the field, we propose software for performing data simulations in the machine olfaction field by generating parameterized sensor array data. The software is implemented as an R language package chemosensors which is open-access, platform-independent and self-contained. We introduce the concept of a virtual sensor array which can be used as a data generation tool. In this work, we describe the data simulation workflow which basically consists of scenario definition, virtual array parameterization and the generation of sensor array data. We also give examples of the processing of the simulated data as proof of concept for the parameterized sensor array data: the benchmarking of classification algorithms, the evaluation of linear- and non-linear regression algorithms, and the biologically inspired processing of sensor array data. All the results presented were obtained under version 0.7.6 of the chemosensors package whose home page is chemosensors.r-forge.r-project.org. PMID:24586410

  4. Data simulation in machine olfaction with the R package chemosensors.

    Directory of Open Access Journals (Sweden)

    Andrey Ziyatdinov

    Full Text Available In machine olfaction, the design of applications based on gas sensor arrays is highly dependent on the robustness of the signal and data processing algorithms. While the practice of testing the algorithms on public benchmarks is not common in the field, we propose software for performing data simulations in the machine olfaction field by generating parameterized sensor array data. The software is implemented as an R language package chemosensors which is open-access, platform-independent and self-contained. We introduce the concept of a virtual sensor array which can be used as a data generation tool. In this work, we describe the data simulation workflow which basically consists of scenario definition, virtual array parameterization and the generation of sensor array data. We also give examples of the processing of the simulated data as proof of concept for the parameterized sensor array data: the benchmarking of classification algorithms, the evaluation of linear- and non-linear regression algorithms, and the biologically inspired processing of sensor array data. All the results presented were obtained under version 0.7.6 of the chemosensors package whose home page is chemosensors.r-forge.r-project.org.

  5. Data simulation in machine olfaction with the R package chemosensors.

    Science.gov (United States)

    Ziyatdinov, Andrey; Perera-Lluna, Alexandre

    2014-01-01

    In machine olfaction, the design of applications based on gas sensor arrays is highly dependent on the robustness of the signal and data processing algorithms. While the practice of testing the algorithms on public benchmarks is not common in the field, we propose software for performing data simulations in the machine olfaction field by generating parameterized sensor array data. The software is implemented as an R language package chemosensors which is open-access, platform-independent and self-contained. We introduce the concept of a virtual sensor array which can be used as a data generation tool. In this work, we describe the data simulation workflow which basically consists of scenario definition, virtual array parameterization and the generation of sensor array data. We also give examples of the processing of the simulated data as proof of concept for the parameterized sensor array data: the benchmarking of classification algorithms, the evaluation of linear- and non-linear regression algorithms, and the biologically inspired processing of sensor array data. All the results presented were obtained under version 0.7.6 of the chemosensors package whose home page is chemosensors.r-forge.r-project.org.

  6. Simulation and analysis of resin flow in injection machine screw

    Institute of Scientific and Technical Information of China (English)

    Ling-feng LI; Samir MEKID

    2008-01-01

    A method with simulation and analysis of the resin flow in a screw is presented to ease the control of some problems that may affect the efficiency and the quality of the product among existing screws in an injection machine. The physical model of a screw is established to represent the stress, the strain, the relationship between velocity and stress, and the temperature of the cells. In this paper, a working case is considered where the velocity and the temperature distributions at any section of the flow are obtained. The analysis of the computational results shows an ability to master various parameters depending on the specifications.

  7. Is the "In Loco Parentis" Doctrine Dead?

    Science.gov (United States)

    Zirkel, Perry A.; Reichner, Henry F.

    1986-01-01

    Reviews history of the doctrine of "in loco parentis." Examines court opinions in which the doctrine has surfaced as an issue in the following areas of litigation: corporal punishment, student searches, school rules, correlative duties, and teacher-student relationship at the college level. Finds that the status and scope of the doctrine…

  8. Statistical simulations of machine errors for LINAC4

    CERN Document Server

    Baylac, M; Froidefond, E; Sargsyan, E

    2006-01-01

    LINAC 4 is a normal conducting H- linac proposed at CERN to provide a higher proton flux to the CERN accelerator chain. It should replace the existing LINAC 2 as injector to the Proton Synchrotron Booster and can also operate in the future as the front end of the SPL, a 3.5 GeV Superconductingg Proton Linac. LINAC 4 consists of a Radio-Frequency Quadrupole, a chopper line, a Drift Tube Linac (DTL) and a Cell Coupled DTL all operating at 352 MHz and finally a Side Coupled Linac at 704 MHz. Beam dynamics was studied and optimized performing end-to-end simulations. This paper presents statistical simulations of machine errors which were performed in order to validate the proposed design.

  9. Direct digital simulation of power semiconductor-controlled electrical machines

    Science.gov (United States)

    Bahnassy, H. M.

    1981-06-01

    Generalized computer programming techniques for simulating power semiconductor-controlled electric machines in coil-variable representation are presented. These techniques are developed primarily for implementation in large scale general purpose computer-aided design and analysis (CADA) circuit programs. To demonstrate the validity of the developed techniques, a coil-variable model of a brushless synchronous generator with an ac exciter and rotating rectifiers was constructed. The performance of the control system (thyristor voltage regulator) is represented by a transfer function block diagram model. The CADA circuit program used is the recently developed SUPER SCEPTRE program. The model is validated using the design data and test results of a 60 kVA brushless generator. Numerous computer simulation cases are presented including the steady state and transient conditions. Brushless generator performance under diode failure faults (opened-diode, shorted-diode) is simulated. The effects of the external faults, at the main generator terminals, on the main generator, as well as its excitation system currents, are simulated.

  10. Machine Learning and Cosmological Simulations I: Semi-Analytical Models

    CERN Document Server

    Kamdar, Harshil M; Brunner, Robert J

    2016-01-01

    We present a new exploratory framework to model galaxy formation and evolution in a hierarchical universe by using machine learning (ML). Our motivations are two-fold: (1) presenting a new, promising technique to study galaxy formation, and (2) quantitatively analyzing the extent of the influence of dark matter halo properties on galaxies in the backdrop of semi-analytical models (SAMs). We use the influential Millennium Simulation and the corresponding Munich SAM to train and test various sophisticated machine learning algorithms (k-Nearest Neighbors, decision trees, random forests and extremely randomized trees). By using only essential dark matter halo physical properties for haloes of $M>10^{12} M_{\\odot}$ and a partial merger tree, our model predicts the hot gas mass, cold gas mass, bulge mass, total stellar mass, black hole mass and cooling radius at z = 0 for each central galaxy in a dark matter halo for the Millennium run. Our results provide a unique and powerful phenomenological framework to explore...

  11. Filter Feeding Mechanism Simulated Machine Paradigms – A Theoretical Approach

    Directory of Open Access Journals (Sweden)

    Channaveerappa. H,

    2014-01-01

    Full Text Available Bionics is the emerging branch of bio engineering where in the structures and functions of organism are utilized to construct a gadget that resembles the structure and performs similar function. The functional principles are also used to construct special gadgets to perform functions in the form of simulated robots. Animal models have also been used in creation of many structures/machines, for example the organization and flight mechanism of birds, echolocation in bats, and internal ear of mammals have been taken as blue prints to design aero planes, radars and telegraphic systems respectively. Here we are using ciliary feeding mechanisms in animals to create a machine that can be used for a particular purpose. Cilia are minute finger like protoplasmic extensions serve different functions like movement, creation of water current propelling and filter feeding in animals. In many invertebrates and lower chordates rotor movements of cilia create whirl pool of water current to obtain food material. Animals those use cilia for feeding are referred to ciliary feeders or filter feeders. The filter feeders are highly diverse in their habit but share common requirements. The filter feeders may be sessile or free swimming forms but the principles of feeding remains the same. In lower chordates the pharngometry of pharynx plays a decisive role in filter feeding. The filter feeding mechanism is highly evolved in animals through well designed evolutionary paradigms.

  12. Simulation and experimental results of hybrid electric machine with a novel flux control strategy

    Directory of Open Access Journals (Sweden)

    Paplicki Piotr

    2015-03-01

    Full Text Available The paper presents selected simulation and experimental results of a hybrid ECPMS-machine (Electric Controlled Permanent Magnet Synchronous Machine. This permanent magnets (PMs excited machine offers an extended magnetic field control capability which makes it suitable for battery electric vehicle (BEV drives. Rotor, stator and the additional direct current control coil of the machine are analyzed in detail. The control system and strategy, the diagram of power supply system and an equivalent circuit model of the ECPMS-machine are presented. Influence of the additional excitation on the performance parameters of the machine, such as: torque, efficiency, speed limits and back-EMF have also been discussed.

  13. SIMULATION SYSTEM FOR FIVE-AXIS NC MACHINING USING GENERAL CUTTING TOOL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A simulation system for five-axis NC machining using general cutting tools is presented. This system differs from other simulation system in that it not only focuses on the geometric simulation but also focuses on the collision detection which is usually not included in NC machining simulation. Besides all of these, estimating cutting forces is also discussed. In order to obtain high efficiency, all algorithms use swept volume modeling technique, so the simulation system is compact and can be performed efficiently.

  14. Modeling and Simulation of Process-Machine Interaction in Grinding of Cemented Carbide Indexable Inserts

    Directory of Open Access Journals (Sweden)

    Wei Feng

    2015-01-01

    Full Text Available Interaction of process and machine in grinding of hard and brittle materials such as cemented carbide may cause dynamic instability of the machining process resulting in machining errors and a decrease in productivity. Commonly, the process and machine tools were dealt with separately, which does not take into consideration the mutual interaction between the two subsystems and thus cannot represent the real cutting operations. This paper proposes a method of modeling and simulation to understand well the process-machine interaction in grinding process of cemented carbide indexable inserts. First, a virtual grinding wheel model is built by considering the random nature of abrasive grains and a kinematic-geometrical simulation is adopted to describe the grinding process. Then, a wheel-spindle model is simulated by means of the finite element method to represent the machine structure. The characteristic equation of the closed-loop dynamic grinding system is derived to provide a mathematic description of the process-machine interaction. Furthermore, a coupling simulation of grinding wheel-spindle deformations and grinding process force by combining both the process and machine model is developed to investigate the interaction between process and machine. This paper provides an integrated grinding model combining the machine and process models, which can be used to predict process-machine interactions in grinding process.

  15. Application of Maintenance Simulate System of NC Machine Tools in Teaching

    Directory of Open Access Journals (Sweden)

    He Xin

    2017-01-01

    Full Text Available The project design is the foundation of training, which can insure the usefulness of human resource development system. The Training Project Maintenance Simulate System of NC Machine Tools is presented based on analyzed contradiction between supply and demand. This paper introduces several scheme of Maintenance Simulate System of NC Machine Tools.

  16. Five-Phase Modular External Rotor PM Machines with Different Rotor Poles: A Comparative Simulation Study

    Directory of Open Access Journals (Sweden)

    A. S. Abdel-Khalik

    2012-01-01

    Full Text Available The performance of fault-tolerant modular permanent magnet machines depends on the proper selection of the pole and slot numbers which result in negligible coupling between phases. The preferred slot and pole number combinations eliminate the effect of low-order harmonics in the stator magnetomotive force and thereby the vibration and stray loss are reduced. In this paper, three external rotor machines with identical machine dimensions are designed with different slots per phase per pole ratios. A simulation study is carried out using finite element analysis to compare the performance of the three machines in terms of machine torque density, ripple torque, core loss, and machine efficiency. A mathematical model based on the conventional-phase-model approach is also used for the comparative study. The simulation study is extended to depict machine performance under fault conditions.

  17. Machine learning and cosmological simulations - I. Semi-analytical models

    Science.gov (United States)

    Kamdar, Harshil M.; Turk, Matthew J.; Brunner, Robert J.

    2016-01-01

    We present a new exploratory framework to model galaxy formation and evolution in a hierarchical Universe by using machine learning (ML). Our motivations are two-fold: (1) presenting a new, promising technique to study galaxy formation, and (2) quantitatively analysing the extent of the influence of dark matter halo properties on galaxies in the backdrop of semi-analytical models (SAMs). We use the influential Millennium Simulation and the corresponding Munich SAM to train and test various sophisticated ML algorithms (k-Nearest Neighbors, decision trees, random forests, and extremely randomized trees). By using only essential dark matter halo physical properties for haloes of M > 1012 M⊙ and a partial merger tree, our model predicts the hot gas mass, cold gas mass, bulge mass, total stellar mass, black hole mass and cooling radius at z = 0 for each central galaxy in a dark matter halo for the Millennium run. Our results provide a unique and powerful phenomenological framework to explore the galaxy-halo connection that is built upon SAMs and demonstrably place ML as a promising and a computationally efficient tool to study small-scale structure formation.

  18. Is "In Consortio Cum Parentibus" the New "In Loco Parentis?"

    Science.gov (United States)

    Henning, Gavin

    2007-01-01

    "In loco parentis" had been the philosophical foundation of higher education policy and practice since 1913 when it was established as a legal doctrine in Gott v. Berea. The doctrine defined the relationship between colleges, students, and parents. That relationship has changed with the death of "in loco parentis" in Dixon v. Alabama Board of…

  19. ANALYSIS AND SIMULATION ON THE MECHANISM OF A NOVEL DUAL-WAVE SHOCK TEST MACHINE

    Institute of Scientific and Technical Information of China (English)

    WANG Gongxian; ZHANG Zhiyi; CHU Deying; SHEN Rongying

    2008-01-01

    For qualifying the anti-shock performance of shipboard equipments and simulating actual underwater explosion environments, a novel dual-wave shock test machine is proposed to increase testing capability of shock test machines as well as to meet certain shock testing specification. The machine can generate a double-pulse acceleration shock for test articles according to specification defined in BV043/85. On the basis of the impact theory, a nonlinear dynamic model of the hydraulically-actuated test machine is established with thorough analysis on its mechanism which involves conversion of gas potential energy and dissipation of kinetic energy. Simulation results have demonstrated that the machine can produce a double-pulse acceleration shock in the time domain or a desired shock response spectrum in the frequency domain, which sets a theoretical base for the construction of the proposed machine.

  20. Design of Experimentation, Artificial Neural Network Simulation and Optimization for Integrated Bamboo Processing Machine

    Directory of Open Access Journals (Sweden)

    P. G. Mehar

    2015-11-01

    Full Text Available In this research work experimentation on integrated bamboo processing machine for splitting and slicing of bamboo has been carried out. This paper presents the experimental investigation of some parameters of integrated bamboo processing machine. In this research paper simulation of experimental data using artificial neural network is carried out. An attempt of minimum-maximum principle has been made to optimize by range bound process for maximizing production rate of integrated bamboo processing machine.

  1. Fluid Dynamics Appearing during Simulated Microgravity Using Random Positioning Machines

    Science.gov (United States)

    Stern, Philip; Casartelli, Ernesto; Egli, Marcel

    2017-01-01

    Random Positioning Machines (RPMs) are widely used as tools to simulate microgravity on ground. They consist of two gimbal mounted frames, which constantly rotate biological samples around two perpendicular axes and thus distribute the Earth’s gravity vector in all directions over time. In recent years, the RPM is increasingly becoming appreciated as a laboratory instrument also in non-space-related research. For instance, it can be applied for the formation of scaffold-free spheroid cell clusters. The kinematic rotation of the RPM, however, does not only distribute the gravity vector in such a way that it averages to zero, but it also introduces local forces to the cell culture. These forces can be described by rigid body analysis. Although RPMs are commonly used in laboratories, the fluid motion in the cell culture flasks on the RPM and the possible effects of such on cells have not been examined until today; thus, such aspects have been widely neglected. In this study, we used a numerical approach to describe the fluid dynamic characteristic occurring inside a cell culture flask turning on an operating RPM. The simulations showed that the fluid motion within the cell culture flask never reached a steady state or neared a steady state condition. The fluid velocity depends on the rotational velocity of the RPM and is in the order of a few centimeters per second. The highest shear stresses are found along the flask walls; depending of the rotational velocity, they can reach up to a few 100 mPa. The shear stresses in the “bulk volume,” however, are always smaller, and their magnitude is in the order of 10 mPa. In conclusion, RPMs are highly appreciated as reliable tools in microgravity research. They have even started to become useful instruments in new research fields of mechanobiology. Depending on the experiment, the fluid dynamic on the RPM cannot be neglected and needs to be taken into consideration. The results presented in this study elucidate the fluid

  2. Fluid Dynamics Appearing during Simulated Microgravity Using Random Positioning Machines.

    Science.gov (United States)

    Wuest, Simon L; Stern, Philip; Casartelli, Ernesto; Egli, Marcel

    2017-01-01

    Random Positioning Machines (RPMs) are widely used as tools to simulate microgravity on ground. They consist of two gimbal mounted frames, which constantly rotate biological samples around two perpendicular axes and thus distribute the Earth's gravity vector in all directions over time. In recent years, the RPM is increasingly becoming appreciated as a laboratory instrument also in non-space-related research. For instance, it can be applied for the formation of scaffold-free spheroid cell clusters. The kinematic rotation of the RPM, however, does not only distribute the gravity vector in such a way that it averages to zero, but it also introduces local forces to the cell culture. These forces can be described by rigid body analysis. Although RPMs are commonly used in laboratories, the fluid motion in the cell culture flasks on the RPM and the possible effects of such on cells have not been examined until today; thus, such aspects have been widely neglected. In this study, we used a numerical approach to describe the fluid dynamic characteristic occurring inside a cell culture flask turning on an operating RPM. The simulations showed that the fluid motion within the cell culture flask never reached a steady state or neared a steady state condition. The fluid velocity depends on the rotational velocity of the RPM and is in the order of a few centimeters per second. The highest shear stresses are found along the flask walls; depending of the rotational velocity, they can reach up to a few 100 mPa. The shear stresses in the "bulk volume," however, are always smaller, and their magnitude is in the order of 10 mPa. In conclusion, RPMs are highly appreciated as reliable tools in microgravity research. They have even started to become useful instruments in new research fields of mechanobiology. Depending on the experiment, the fluid dynamic on the RPM cannot be neglected and needs to be taken into consideration. The results presented in this study elucidate the fluid

  3. Co-Simulation of an Inverter Fed Permanent Magnet Synchronous Machine

    Directory of Open Access Journals (Sweden)

    Kiss Gergely Máté

    2014-10-01

    Full Text Available Co-simulation is a method which makes it possible to study the electric machine and its drive at once, as one system. By taking into account the actual inverter voltage waveforms in a finite element model instead of using only the fundamental, we are able to study the electrical machine's behavior in more realistic scenario. The recent increase in the use of variable speed drives justifies the research on such simulation techniques. In this paper we present the co-simulation of an inverter fed permanent magnet synchronous machine. The modelling method employs an analytical variable speed drive model and a finite element electrical machine model. By linking the analytical variable speed drive model together with a finite element model the complex simulation model enables the investigation of the electrical machine during actual operation. The methods are coupled via the results. This means that output of the finite element model serves as an input to the analytical model, and the output of the analytical model provides the input of the finite element model for a different simulation, thus enabling the finite element simulation of an inverter fed machine. The resulting speed and torque characteristics from the analytical model and the finite element model show a good agreement. The experiences with the co-simulation technique encourage further research and effort to improve the method.

  4. Motion and Virtual Cutting Simulation System for a Five-Axis Virtual Machine Tool

    Directory of Open Access Journals (Sweden)

    Rong-Shean Lee

    2011-09-01

    Full Text Available Since five-axis machine tools are very costly and their use requires a high level of knowledge and expertise, a virtual machine tool must be used to simulate five-axis machine tool operation. Configuration code or a mechanism topology matrix must be used to describe a machine tool, and can be used as the framework for design of a virtual machine tool system. The first step is to isolate the basic motions of each element of a virtual machine tool and then establish their coordinate systems. The establishment of a node tree allows coordinate transformation matrices for virtual motion components to be derived, which are then used to simulate movements. The simulation of virtual cutting must take into consideration both accuracy and efficiency. While either a GPU or CPU can be used to perform calculations, there are currently restrictions on GPU memory use which results in relatively lower accuracy. In contrast, a CPU can perform calculations using an adaptive octree with voxels and multithreading to yield sufficient accuracy and efficiency. A five-axis virtual machine tool motion and virtual cutting simulation system was written in C/C++ with OpenGL and OpenMP, and can perform real-time cutting simulations.

  5. Modelling and Simulation of a Synchronous Machine with Power Electronic Systems

    DEFF Research Database (Denmark)

    Chen, Zhe; Blaabjerg, Frede

    2005-01-01

    This paper reports the modeling and simulation of a synchronous machine with a power electronic interface in direct phase model. The implementation of a direct phase model of synchronous machines in MATLAB/SIMULINK is presented .The power electronic system associated with the synchronous machine...... is modelled in SIMULINK as well. The resulting model can more accurately represent non-idea situations such as non-symmetrical parameters of the electrical machines and unbalance conditions. The model may be used for both steady state and large-signal dynamic analysis. This is particularly useful...

  6. Modelling and Simulation of a Synchronous Machine with Power Electronic Systems

    DEFF Research Database (Denmark)

    Chen, Zhe; Blaabjerg, Frede

    2005-01-01

    This paper reports the modeling and simulation of a synchronous machine with a power electronic interface in direct phase model. The implementation of a direct phase model of synchronous machines in MATLAB/SIMULINK is presented .The power electronic system associated with the synchronous machine...... is modelled in SIMULINK as well. The resulting model can more accurately represent non-idea situations such as non-symmetrical parameters of the electrical machines and unbalance conditions. The model may be used for both steady state and large-signal dynamic analysis. This is particularly useful...

  7. Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in Chile.

    Science.gov (United States)

    Garavelli, Lysel; Colas, François; Verley, Philippe; Kaplan, David Michael; Yannicelli, Beatriz; Lett, Christophe

    2016-01-01

    In marine benthic ecosystems, larval connectivity is a major process influencing the maintenance and distribution of invertebrate populations. Larval connectivity is a complex process to study as it is determined by several interacting factors. Here we use an individual-based, biophysical model, to disentangle the effects of such factors, namely larval vertical migration, larval growth, larval mortality, adults fecundity, and habitat availability, for the marine gastropod Concholepas concholepas (loco) in Chile. Lower transport success and higher dispersal distances are observed including larval vertical migration in the model. We find an overall decrease in larval transport success to settlement areas from northern to southern Chile. This spatial gradient results from the combination of current direction and intensity, seawater temperature, and available habitat. From our simulated connectivity patterns we then identify subpopulations of loco along the Chilean coast, which could serve as a basis for spatial management of this resource in the future.

  8. Calibrating transport lines using LOCO techniques

    Energy Technology Data Exchange (ETDEWEB)

    Yves Roblin

    2011-09-01

    With the 12GeV upgrade underway at CEBAF, there is a need to re-characterize the beamlines after the modifications made to it to accommodate running at higher energies. We present a linear perturbation approach to calibrating the optics model of transport lines. This method is adapted from the LOCO method in use for storage rings. We consider the effect of quadrupole errors, dipole construction errors as well as beam position monitors and correctors calibrations. The ideal model is expanded to first order in Taylor series of the quadrupole errors. A set of difference orbits obtained by exciting the correctors along the beamline is taken, yielding the measured response matrix. An iterative procedure is invoked and the quadrupole errors as well as beam position monitors and corrector calibration factors are obtained. Here we present details of the method and results of first measurements at CEBAF in early 2011.

  9. Kinematic simulation of a parallel NC machine tool in the manufacturing process

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-min; FAN Yu; JIA Dong-yun; ZOU Qiu-ling; WU Ying

    2006-01-01

    Aimed at enhancing the research status of parallel machine tools,this paper introduces the structure of a 6-SPS parallel machine tool and explains the application significance of the kinematic simulation of the manufacturing process.The simulation software was developed in Microsoft Visual C++6.0 using OpenGL API functions.The data flows are presented.Finally, a simulation application of odd leaf hyperboloid is performed before the manufacturing process; the kinematic simulation demonstrates the rationale of trace planning and the feasibility of manufacturing instruction.

  10. Etude et simulation des groupes convertisseurs-machines synchrones a six phases

    Science.gov (United States)

    Doyon, Jean-Francois

    Since many years, multiphase (n > 3) machines represent a growing research interest in the electrical machines domain. This type of machine can be used for many systems like automotive electrical traction, electric ship propulsion, wind farms or high-power industrial applications. Above all multiphase machines, the six phases wounded rotor synchronous machine brings a huge interest. Subsequently, using that kind of machine in any application requires a good understanding of the machine model and its respective converters. Hence, simulation represents a great way to study the behaviour and design of such applications that uses six phases wounded rotor synchronous machines. The present research concerns the study and simulation of six phase synchronous machinesconverters systems. From this project resulted the implementation of the six phases wound rotor salient pole synchronous machine in the Demos library of Matlab SimPowerSytems. In terms of study, a six phase machine electric drive is designed as well as a six phase machine implementation in a type 4 wind farm. The modeling of the six phase synchronous machine is fully detailed for the electrical part and the mechanical part. Then, the voltage source inverter electric drive with hysteresis control is conceived. Simulations of torque control, speed control and degraded mode of the machine are executed. The results illustrate the electric drive efficiency. This is followed by the type 4 wind turbine application of the machine. The wind farm is connected to a 120 kV grid, where a voltage drop fault appears at the 120 kV bar for a duration of six 60 Hz cycles. The results show a good operation of the regulators during the fault. This application is also subjected to a degraded mode, where results illustrate once again a good system regulation. Also, for the electric drive and the wind farm applications, a comparative study is made for the use of an asymmetrical versus symmetrical winding configuration of the machine

  11. Fluid motion for microgravity simulations in a random positioning machine

    NARCIS (Netherlands)

    Leguy, C.A.D.; Delfos, R.; Pourquie, M.J.M.B.; Poelma, C.; Krooneman, J.; Westerweel, J.; van Loon, J.J.W.A.

    2011-01-01

    To understand the role of gravity in biological systems one may decrease inertial acceleration by going into free-fall conditions such as available on various platforms. These experiments are cumbersome and expensive. Thus, alternative techniques like Random Positioning Machines (RPM) are now widely

  12. Introducing LoCo, a Logic for Configuration Problems

    CERN Document Server

    Aschinger, Markus; Gottlob, Georg; 10.4204/EPTCS.65.4

    2011-01-01

    In this paper we present the core of LoCo, a logic-based high-level representation language for expressing configuration problems. LoCo shall allow to model these problems in an intuitive and declarative way, the dynamic aspects of configuration notwithstanding. Our logic enforces that configurations contain only finitely many components and reasoning can be reduced to the task of model construction.

  13. Introducing LoCo, a Logic for Configuration Problems

    Directory of Open Access Journals (Sweden)

    Markus Aschinger

    2011-08-01

    Full Text Available In this paper we present the core of LoCo, a logic-based high-level representation language for expressing configuration problems. LoCo shall allow to model these problems in an intuitive and declarative way, the dynamic aspects of configuration notwithstanding. Our logic enforces that configurations contain only finitely many components and reasoning can be reduced to the task of model construction.

  14. Inrush Current Simulation of Two Windings Power Transformer using Machine Parameters Estimated by Design Procedure of Winding Structure

    Science.gov (United States)

    Tokunaga, Yoshitaka; Kubota, Kunihiro

    This paper presents estimation techniques of machine parameters for two windings power transformer using design procedure of winding structure. Especially, it is very difficult to obtain machine parameters for transformers in customers' facilities. Using estimation techniques, machine parameters could be calculated from the only nameplate data of these transformers. Subsequently, EMTP-ATP simulation of the inrush current was carried out using machine parameters estimated by design procedure of winding structure and simulation results were reproduced measured waveforms.

  15. Inrush Current Simulation of Power Transformer using Machine Parameters Estimated by Design Procedure of Winding Structure and Genetic Algorithm

    Science.gov (United States)

    Tokunaga, Yoshitaka

    This paper presents estimation techniques of machine parameters for power transformer using design procedure of transformer and genetic algorithm with real coding. Especially, it is very difficult to obtain machine parameters for transformers in customers' facilities. Using estimation techniques, machine parameters could be calculated from the only nameplate data of these transformers. Subsequently, EMTP-ATP simulation of the inrush current was carried out using machine parameters estimated by techniques developed in this study and simulation results were reproduced measured waveforms.

  16. Human Machine Interaction by Simulation of Dynamics of Construction Machinery

    DEFF Research Database (Denmark)

    Langer, Thomas Heegaard

    This industrial Ph.D. project concerns whole-body vibrations in human operated construction machinery. The emissions of these vibrations is closely related to the subjective experience of comfort and in some cases these vibrations can occur in a level which can cause the operator back disorders...... on long term basis. Whole-body vibrations are potential damaging for the human operator in a frequency range for which the dynamics of the machines are dominated by the inputs of the operator. The objective of this project is to reduce the amount of potential damaging wholebody vibrations for two...... different kinds of machinery; an articulated backhoe loader and an articulated dump truck. In this work a standardized procedure containing a set of duty cycles for measuring and declaring whole-body vibrations has been proposed for both of these machines. The result of the measuring is important...

  17. Man-Machine Interface Design for Modeling and Simulation Software

    Directory of Open Access Journals (Sweden)

    Arnstein J. Borstad

    1986-07-01

    Full Text Available Computer aided design (CAD systems, or more generally interactive software, are today being developed for various application areas like VLSI-design, mechanical structure design, avionics design, cartographic design, architectual design, office automation, publishing, etc. Such tools are becoming more and more important in order to be productive and to be able to design quality products. One important part of CAD-software development is the man-machine interface (MMI design.

  18. Simulation of Alpha-Channeling in Mirror Machines

    Energy Technology Data Exchange (ETDEWEB)

    A.I. Zhmoginov, N.J. Fisch

    2008-03-17

    Applying α-channeling techniques to mirror machines can significantly increase their effective reactivity, thus making open configurations more advantageous for practical fusion. A large fraction of α particle energy can be extracted using rf waves. Effects employed to cool α particles can also in principle be used to heat the fusion ions; the possibility to design a configuration of rf waves which could be used to perform both tasks is demonstrated.

  19. Design of Experimentation, Artificial Neural Network Simulation and Optimization for Integrated Bamboo Processing Machine

    OpenAIRE

    P. G. Mehar; Dr.A.V.Vanalkar

    2015-01-01

    In this research work experimentation on integrated bamboo processing machine for splitting and slicing of bamboo has been carried out. This paper presents the experimental investigation of some parameters of integrated bamboo processing machine. In this research paper simulation of experimental data using artificial neural network is carried out. An attempt of minimum-maximum principle has been made to optimize by range bound process for maximizing production rate of integrated b...

  20. Human Machine Interaction by Simulation of Dynamics of Construction Machinery

    DEFF Research Database (Denmark)

    Langer, Thomas Heegaard

    different kinds of machinery; an articulated backhoe loader and an articulated dump truck. In this work a standardized procedure containing a set of duty cycles for measuring and declaring whole-body vibrations has been proposed for both of these machines. The result of the measuring is important......-body vibration exposure was more than 20 percent and at the same time the fuel consumption was reduced significant. Training of operators is hence beneficial for both employees and employers of the construction industry. The whole-body vibration exposure on operators of dump trucks are dominated by off...

  1. Molecular dynamics simulation on a network of workstations using a machine-independent parallel programming language.

    OpenAIRE

    1991-01-01

    Molecular dynamics simulations investigate local and global motion in molecules. Several parallel computing approaches have been taken to attack the most computationally expensive phase of molecular simulations, the evaluation of long range interactions. This paper develops a straightforward but effective algorithm for molecular dynamics simulations using the machine-independent parallel programming language, Linda. The algorithm was run both on a shared memory parallel computer and on a netw...

  2. Modelling and simulation of effect of ultrasonic vibrations on machining of Ti6Al4V.

    Science.gov (United States)

    Patil, Sandip; Joshi, Shashikant; Tewari, Asim; Joshi, Suhas S

    2014-02-01

    The titanium alloys cause high machining heat generation and consequent rapid wear of cutting tool edges during machining. The ultrasonic assisted turning (UAT) has been found to be very effective in machining of various materials; especially in the machining of "difficult-to-cut" material like Ti6Al4V. The present work is a comprehensive study involving 2D FE transient simulation of UAT in DEFORM framework and their experimental characterization. The simulation shows that UAT reduces the stress level on cutting tool during machining as compared to that of in continuous turning (CT) barring the penetration stage, wherein both tools are subjected to identical stress levels. There is a 40-45% reduction in cutting forces and about 48% reduction in cutting temperature in UAT over that of in CT. However, the reduction magnitude reduces with an increase in the cutting speed. The experimental analysis of UAT process shows that the surface roughness in UAT is lower than in CT, and the UATed surfaces have matte finish as against the glossy finish on the CTed surfaces. Microstructural observations of the chips and machined surfaces in both processes reveal that the intensity of thermal softening and shear band formation is reduced in UAT over that of in CT.

  3. The Lunar Occultation Observer (LOCO) -- A Nuclear Astrophysics All-Sky Survey Mission Concept

    Science.gov (United States)

    Miller, R. S.; Bonamente, M.; Burgess, J. M.; Jenke, P.; Lawrence, D. J.; O'Brien, S.; Orr, M. R.; Paciesas, W. S.; Young, C. A.

    2009-03-01

    The Lunar Occultation Observer (LOCO) is a new γ-ray astrophysics mission concept expected to have unprecedented sensitivity in the nuclear regime. Operating in lunar orbit, LOCO will utilize lunar occultation imaging to survey and probe the cosmos.

  4. Laser-assisted machining process simulation for precision mould/die manufacturing

    Directory of Open Access Journals (Sweden)

    Zeng Quanren

    2015-01-01

    Full Text Available Laser-assisted machining (LAM is a kind of thermally assisted manufacturing process which preheats workpiece material with a highly-localized laser beam and then is followed by a conventional machining operation. It could greatly improve the machinability and gives better machining quality, especially suitable for hard-to-cut materials such as superalloys, tool steels. For manufacturing the high-precision moulds/dies that could fabricate micro and precision components, the thermal assistance at the local cutting zone, will help to lower the cutting force and consequently improve the internal surface quality of the machined moulds/dies. In this paper, a numerical study of the laser-assisted cutting of plastic mould steel NAK80 is reported. The simulation of LAM of NAK80 is realized by combining two procedures: simulation of moving laser heat source applied on the local surface of workpiece which causes the corresponding temperature field arise and material soften, and simulation of the subsequent cutting processes. This research will offer the die/mould manufacturers a more efficient planning tool for the fabrication of the micro, precision dies/moulds of high surface quality, and hence, for forming the high-quality micro components as well as for longer die/mould life.

  5. Application of Local Fourier Transform to Mathematical Simulation of Synchronous Machines with Valve Excitation Systems

    Directory of Open Access Journals (Sweden)

    Fedotov A.

    2017-02-01

    Full Text Available The article proposes a method of mathematical simulation of electrical machines with thyristor exciters on the basis of the local Fourier transform. The present research demonstrates that this method allows switching from a variable structure model to a constant structure model. Transition from the continuous variables to the discrete variables is used. The numerical example is given in the paper.

  6. Application of Local Fourier Transform to Mathematical Simulation of Synchronous Machines with Valve Excitation Systems

    Science.gov (United States)

    Fedotov, A.; Fedotov, E.; Bahteev, K.

    2017-02-01

    The article proposes a method of mathematical simulation of electrical machines with thyristor exciters on the basis of the local Fourier transform. The present research demonstrates that this method allows switching from a variable structure model to a constant structure model. Transition from the continuous variables to the discrete variables is used. The numerical example is given in the paper.

  7. The Value Simulation-Based Learning Added to Machining Technology in Singapore

    Science.gov (United States)

    Fang, Linda; Tan, Hock Soon; Thwin, Mya Mya; Tan, Kim Cheng; Koh, Caroline

    2011-01-01

    This study seeks to understand the value simulation-based learning (SBL) added to the learning of Machining Technology in a 15-week core subject course offered to university students. The research questions were: (1) How did SBL enhance classroom learning? (2) How did SBL help participants in their test? (3) How did SBL prepare participants for…

  8. Energy conservation at air-jet weaving machines by means of flow simulation; Energieeinsparung an Luftwebmaschinen durch Stroemungssimulation

    Energy Technology Data Exchange (ETDEWEB)

    Jungbecker, Philip Alexander

    2012-07-01

    The author of the book under consideration reports on the systematics for a significant reduction of the consumption of compressed air of air-jet weaving machines. Various factors such as the nozzle shape, reed texture, machine parameters and material of the weft yarn are considered. The principal item of the systematics is a validated numerical simulation of the flow field and weft insertion. Virtual modifications at the weaving machine are performed by means of the simulation.

  9. Optics Corrections with LOCO in the Fermilab Booster

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Cheng-Yang [Fermilab; Prost, Lionel [Fermilab; Seiya, Kiyomi [Fermilab; Triplett, A. Kent [Fermilab

    2016-06-01

    The optics of the Fermilab Booster has been corrected with LOCO (Linear Optics from Closed Orbits). However, the first corrections did not show any improvement in capture efficiency at injection. A detailed analysis of the results showed that the problem lay in the MADX optics file. Both the quadrupole and chromatic strengths were originally set as constants independent of beam energy. However, careful comparison between the measured and calculated tunes and chromatcity show that these strengths are energy dependent. After the MADX model was modified with these new energy dependent strengths, the LOCO corrected lattice has been applied to Booster. The effect of the corrected lattice will be discussed here.

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

    Directory of Open Access Journals (Sweden)

    Srisawat Supsomboon

    2014-01-01

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

  11. DESIGNING A FINITE STATE MACHINE SIMULATOR TO DETECT LOOPS FOR ALICE DETECTOR CONTROL SYSTEM

    CERN Document Server

    Yogatama, Bobbi Winema

    2017-01-01

    This paper present the design and implementation of a Finite State Machine simulator to provoke loops in ALICE Detector Control System (DCS). Loops in a Finite State Machine can be very harmful for the control system and need to be prevented. One way to prevent loops is to simulate the designed Finite State Machine using a simulator that can detect all of the possible conditions that can provoke loops. Further correction can then be made after the loops are detected in the control system. The proposed simulator is able to get the structure of any unknown FSM, get every datapoint elements that are associated with the FSM, and find every possible datapoint combinations that can provoke loops in the FSM. At the end of the project, we tested the simulator on a sample FSM with loops and a real FSM that belongs to the ALICE PHOton Spectrometer (PHOS). The testing results indicate that the simulator is able to detect every possible condition that can cause loops in the FSM.

  12. Implementation of a Microcode-controlled State Machine and Simulator in AVR Microcontrollers (MICoSS

    Directory of Open Access Journals (Sweden)

    S. Korbel

    2005-01-01

    Full Text Available This paper describes the design of a microcode-controlled state machine and its software implementation in Atmel AVR microcontrollers. In particular, ATmega103 and ATmega128 microcontrollers are used. This design is closely related to the software implementation of a simulator in AVR microcontrollers. This simulator communicates with the designed state machine and presents a complete design environment for microcode development and debugging. These two devices can be interconnected by a flat cable and linked to a computer through a serial or USB interface.Both devices share the control software that allows us to create and edit microprograms and to control the whole state machine. It is possible to start, cancel or step through the execution of the microprograms. The operator can also observe the current state of the state machine. The second part of the control software enables the operator to create and compile simulating programs. The control software communicates with both devices using commands. All the results of this communication are well arranged in dialog boxes and windows. 

  13. Merged or monolithic? Using machine-learning to reconstruct the dynamical history of simulated star clusters

    Science.gov (United States)

    Pasquato, Mario; Chung, Chul

    2016-05-01

    Context. Machine-learning (ML) solves problems by learning patterns from data with limited or no human guidance. In astronomy, ML is mainly applied to large observational datasets, e.g. for morphological galaxy classification. Aims: We apply ML to gravitational N-body simulations of star clusters that are either formed by merging two progenitors or evolved in isolation, planning to later identify globular clusters (GCs) that may have a history of merging from observational data. Methods: We create mock-observations from simulated GCs, from which we measure a set of parameters (also called features in the machine-learning field). After carrying out dimensionality reduction on the feature space, the resulting datapoints are fed in to various classification algorithms. Using repeated random subsampling validation, we check whether the groups identified by the algorithms correspond to the underlying physical distinction between mergers and monolithically evolved simulations. Results: The three algorithms we considered (C5.0 trees, k-nearest neighbour, and support-vector machines) all achieve a test misclassification rate of about 10% without parameter tuning, with support-vector machines slightly outperforming the others. The first principal component of feature space correlates with cluster concentration. If we exclude it from the regression, the performance of the algorithms is only slightly reduced.

  14. Merged or monolithic? Using machine-learning to reconstruct the dynamical history of simulated star clusters

    CERN Document Server

    Pasquato, Mario

    2016-01-01

    Context. Machine-Learning (ML) solves problems by learning patterns from data, with limited or no human guidance. In Astronomy, it is mainly applied to large observational datasets, e.g. for morphological galaxy classification. Aims. We apply ML to gravitational N-body simulations of star clusters that are either formed by merging two progenitors or evolved in isolation, planning to later identify Globular Clusters (GCs) that may have a history of merging from observational data. Methods. We create mock-observations from simulated GCs, from which we measure a set of parameters (also called features in the machine-learning field). After dimensionality reduction on the feature space, the resulting datapoints are fed to various classification algorithms. Using repeated random subsampling validation we check whether the groups identified by the algorithms correspond to the underlying physical distinction between mergers and monolithically evolved simulations. Results. The three algorithms we considered (C5.0 tree...

  15. Retrieval of Similar Objects in Simulation Data Using Machine Learning Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Cantu-Paz, E; Cheung, S-C; Kamath, C

    2003-06-19

    Comparing the output of a physics simulation with an experiment is often done by visually comparing the two outputs. In order to determine which simulation is a closer match to the experiment, more quantitative measures are needed. This paper describes our early experiences with this problem by considering the slightly simpler problem of finding objects in a image that are similar to a given query object. Focusing on a dataset from a fluid mixing problem, we report on our experiments using classification techniques from machine learning to retrieve the objects of interest in the simulation data. The early results reported in this paper suggest that machine learning techniques can retrieve more objects that are similar to the query than distance-based similarity methods.

  16. Simulation and Optimization of Contactless Power Transfer System for Rotary Ultrasonic Machining

    Directory of Open Access Journals (Sweden)

    Wang Xinwei

    2016-01-01

    Full Text Available In today’s rotary ultrasonic machining (RUM, the power transfer system is based on a contactless power system (rotary transformer rather than the slip ring that cannot cope with high-speed rotary of the tool. The efficiency of the rotary transformer is vital to the whole rotary ultrasonic machine. This paper focused on simulation of the rotary transformer and enhancing the efficiency of the rotary transformer by optimizing three main factors that influence its efficiency, including the gap between the two ferrite cores, the ratio of length and width of the ferrite core and the thickness of ferrite. The finite element model of rotary transformer was built on Maxwell platform. Simulation and optimization work was based on the finite element model. The optimization results compared with the initial simulation result showed an approximate 18% enhancement in terms of efficiency, from 77.69% to 95.2%.

  17. A Novel Cogging Torque Simulation Method for Permanent-Magnet Synchronous Machines

    Directory of Open Access Journals (Sweden)

    Chun-Yu Hsiao

    2011-12-01

    Full Text Available Cogging torque exists between rotor mounted permanent magnets and stator teeth due to magnetic attraction and this is an undesired phenomenon which produces output ripple, vibration and noise in machines. The purpose of this paper is to study the existence and effects of cogging torque, and to present a novel, rapid, half magnet pole pair technique for forecasting and evaluating cogging torque. The technique uses the finite element method as well as Matlab research and development oriented software tools to reduce numerous computing jobs and simulation time. An example of a rotor-skewed structure used to reduce cogging torque of permanent magnet synchronous machines is evaluated and compared with a conventional analysis method for the same motor to verify the effectiveness of the proposed approach. The novel method is proved valuable and suitable for large-capacity machine design.

  18. The Concept of In Loco Parentis in Higher Education.

    Science.gov (United States)

    Harms, Herman Edward

    Institutions of higher education have long stood in loco parentis to their students. This concept is now widely challenged. This paper examines the evolution of the concept and discusses 29 court cases, beginning with a case heard in a Maine court in 1847. The evidence indicates that the future of the concept is unpredictable. Procedural due…

  19. Colleges' Increasing Exposure to Liability: The New "In Loco Parentis."

    Science.gov (United States)

    Szablewicz, James J.; Gibbs, Annette

    1987-01-01

    Outlines the history of the concept of "in loco parentis" and the relationship between college students and their institutions. During the 1960's the concept was no longer evident at the college level, but in the 1980's court trends are beginning to show a rebirth (with revisions) of the doctrine. Includes discussion of court litigation.…

  20. Institutionalizing in Loco Parentis after Gott v. Berea College (1913)

    Science.gov (United States)

    Loss, Christopher P.

    2014-01-01

    Background/Context: The institutionalization of in loco parentis in the wake of Gott v. Berea College (1913) marked a major turning point in the evolution of student management theory and practice. Focusing on the crucial decade of the 1920s, when American higher education first became a mass enterprise, this study explores the interaction of…

  1. "In Loco Parentis": A Relationship Between Parent, State and Child

    Science.gov (United States)

    Shaw, Jenny

    1977-01-01

    Archbishop Ussher (1645) in explaining why all superiors were called parents called upon the idea of patriarchal authority. This paper considers the social implications of the same philosophy as it is represented by the practice of education authorities standing "in loco parentis" to their pupils. (Editor)

  2. Aurelia, nadja y el amor loco Una estetica del amor

    OpenAIRE

    Tapias Ospina, Claudia; Editora Revistas Pluma y Universitas Humanística.

    2004-01-01

    El presente ensayo dilucida la íntima relación existente entre Aurelia de Gérard de Nerval (1) -obra escrita en 1853 en pleno Romanticismo- y Nadja (1928) y El amor loco (1937) de André Bretón -escritas durante el auge del movimiento Surrealista (2).

  3. End mill tools integration in CNC machining for rapid manufacturing processes: simulation studies

    Directory of Open Access Journals (Sweden)

    Muhammed Nafis Osman Zahid

    2015-01-01

    Full Text Available Computer numerical controlled (CNC machining has been recognized as a manufacturing process that is capable of producing metal parts with high precision and reliable quality, whereas many additive manufacturing methods are less capable in these respects. The introduction of a new layer-removal methodology that utilizes an indexing device to clamp the workpiece can be used to extend CNC applications into the realm of rapid manufacturing (CNC-RM processes. This study aims to improve the implementation of CNC machining for RM by formulating a distinct approach to integrate end mill tools during finishing processes. A main objective is to enhance process efficiency by minimizing the staircasing effect of layer removal so as to improve the quality of machined parts. In order to achieve this, different types of end mill tools are introduced to cater for specific part surfaces during finishing operations. Virtual machining simulations are executed to verify the method and the implications. The findings indicate the advantages of the approach in terms of cutting time and excess volume left on the parts. It is shown that using different tools for finishing operations will improve the capabilities of CNC machining for rapid manufacturing applications.

  4. One- and two-dimensional Stirling machine simulation using experimentally generated reversing flow turbuulence models

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, L.F. [Univ. of Minnesota, Minneapolis, MN (United States)

    1990-08-01

    The activities described in this report do not constitute a continuum but rather a series of linked smaller investigations in the general area of one- and two-dimensional Stirling machine simulation. The initial impetus for these investigations was the development and construction of the Mechanical Engineering Test Rig (METR) under a grant awarded by NASA to Dr. Terry Simon at the Department of Mechanical Engineering, University of Minnesota. The purpose of the METR is to provide experimental data on oscillating turbulent flows in Stirling machine working fluid flow path components (heater, cooler, regenerator, etc.) with particular emphasis on laminar/turbulent flow transitions. Hence, the initial goals for the grant awarded by NASA were, broadly, to provide computer simulation backup for the design of the METR and to analyze the results produced. This was envisaged in two phases: First, to apply an existing one-dimensional Stirling machine simulation code to the METR and second, to adapt a two-dimensional fluid mechanics code which had been developed for simulating high Rayleigh number buoyant cavity flows to the METR. The key aspect of this latter component was the development of an appropriate turbulence model suitable for generalized application to Stirling simulation. A final-step was then to apply the two-dimensional code to an existing Stirling machine for which adequate experimental data exist. The work described herein was carried out over a period of three years on a part-time basis. Forty percent of the first year`s funding was provided as a match to the NASA funds by the Underground Space Center, University of Minnesota, which also made its computing facilities available to the project at no charge.

  5. Simulating three-dimensional hydrodynamics on a cellular-automata machine

    CERN Document Server

    Adler, C; Margolus, N H; Rothman, D H; Adler, Christopher; Boghosian, Bruce M; Margolus, Norman; Rothman, Daniel H

    1995-01-01

    We demonstrate how three-dimensional fluid flow simulations can be carried out on the Cellular Automata Machine 8 (CAM-8), a special-purpose computer for cellular-automata computations. The principal algorithmic innovation is the use of a lattice-gas model with a 16-bit collision operator that is specially adapted to the machine architecture. It is shown how the collision rules can be optimized to obtain a low viscosity of the fluid. Predictions of the viscosity based on a Boltzmann approximation agree well with measurements of the viscosity made on CAM-8. Several test simulations of flows in simple geometries -- channels, pipes, and a cubic array of spheres -- are carried out. Measurements of average flux in these geometries compare well with theoretical predictions.

  6. Simulation of the Carton Erection for the Rubber Glove Packing Machine Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Jewsuwun Kawin

    2017-01-01

    Full Text Available The rubber glove packing machine had been designed an important function which worked with folding carton. Each folded paper carton would be pulled to be erected by vacuum cups. Some carton could not completely form because of an unsuitable design of the erector. Cartons were collapsed or buckling while pulled by vacuum cups that cause to sudden stop the packing process and affect to number and cost of rubber glove production. This research aimed to use simulation method to erect the folded carton. Finite element (FE model of the rubber glove carton was created with shell elements. The orthotropic material properties were employed to specify FE model for analysis erection behavior of the folding carton. Vacuum cups number, positions and rotation points were simulated until obtained a good situation of the folding carton erector. Subsequently, finite element analysis results will be used to fabricate erector of the rubber glove packing machine in a further work.

  7. JACOS: AI-based simulation system for man-machine system behavior in NPP

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Kazuo; Yokobayashi, Masao; Tanabe, Fumiya [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kawase, Katsumi [CSK Corp., Tokyo (Japan); Komiya, Akitoshi [Computer Associated Laboratory, Inc., Hitachinaka, Ibaraki (Japan)

    2001-08-01

    A prototype of a computer simulation system named JACOS (JAERI COgnitive Simulation system) has been developed at JAERI (Japan Atomic Energy Research Institute) to simulate the man-machine system behavior in which both the cognitive behavior of a human operator and the plant behavior affect each other. The objectives of this system development is to provide man-machine system analysts with detailed information on the cognitive process of an operator and the plant behavior affected by operator's actions in accidental situations of a nuclear power plant. The simulation system consists of an operator model and a plant model which are coupled dynamically. The operator model simulates an operator's cognitive behavior in accidental situations based on the decision ladder model of Rasmussen, and is implemented using the AI-techniques of the distributed cooperative inference method with the so-called blackboard architecture. Rule-based behavior is simulated using knowledge representation with If-Then type of rules. Knowledge-based behavior is simulated using knowledge representation with MFM (Multilevel Flow Modeling) and qualitative reasoning method. Cognitive characteristics of attentional narrowing, limitation of short-term memory, and knowledge recalling from long-term memory are also taken into account. The plant model of a 3-loop PWR is also developed using a best estimate thermal-hydraulic analysis code RELAP5/MOD2. This report is prepared as User's Manual for JACOS. The first chapter of this report describes both operator and plant models in detail. The second chapter includes instructive descriptions for program installation, building of a knowledge base for operator model, execution of simulation and analysis of simulation results. The examples of simulation with JACOS are shown in the third chapter. (author)

  8. A Study of Synchronous Machine Model Implementations in Matlab/Simulink Simulations for New and Renewable Energy Systems

    DEFF Research Database (Denmark)

    Chen, Zhe; Blaabjerg, Frede; Iov, Florin

    2005-01-01

    A direct phase model of synchronous machines implemented in MA TLAB/SIMULINK is presented. The effects of the machine saturation have been included. Simulation studies are performed under various conditions. It has been demonstrated that the MATLAB/SIMULINK is an effective tool to study the complex...

  9. A Study of Synchronous Machine Model Implementations in Matlab/Simulink Simulations for New and Renewable Energy Systems

    DEFF Research Database (Denmark)

    Chen, Zhe; Blaabjerg, Frede; Iov, Florin

    2005-01-01

    A direct phase model of synchronous machines implemented in MA TLAB/SIMULINK is presented. The effects of the machine saturation have been included. Simulation studies are performed under various conditions. It has been demonstrated that the MATLAB/SIMULINK is an effective tool to study the complex...

  10. Hierarchical analytical and simulation modelling of human-machine systems with interference

    Science.gov (United States)

    Braginsky, M. Ya; Tarakanov, D. V.; Tsapko, S. G.; Tsapko, I. V.; Baglaeva, E. A.

    2017-01-01

    The article considers the principles of building the analytical and simulation model of the human operator and the industrial control system hardware and software. E-networks as the extension of Petri nets are used as the mathematical apparatus. This approach allows simulating complex parallel distributed processes in human-machine systems. The structural and hierarchical approach is used as the building method for the mathematical model of the human operator. The upper level of the human operator is represented by the logical dynamic model of decision making based on E-networks. The lower level reflects psychophysiological characteristics of the human-operator.

  11. Extending the features of RBMK refuelling machine simulator with a training tool based on virtual reality

    Energy Technology Data Exchange (ETDEWEB)

    Khoudiakov, M.; Slonimsky, V.; Mitrofanov, S. (and others)

    2004-07-01

    The paper describes a continuation of efforts of an international Russian - Norwegian joint team to improve operational safety during the refuelling process of an RBMK-type reactor by implementing a training simulator based on an innovative Virtual Reality (VR) approach. During the preceding 1st stage of the project a display-based simulator was extended with VR models of the real Refuelling Machine (RM) and its environment in order to improve both the learning process and operation's effectiveness. The simulator's challenge is to support the performance (operational activity) of RM operational staff firstly by helping them to develop basic knowledge and skills as well as to keep skilled staff in close touch with the complex machinery of the Refuelling Machine. During the 2nd stage of the joint project the functional scope of the VR-simulator was greatly enhanced - firstly, by connecting to the RBMK-unit full-scope simulator, and, secondly, by including a training program and simulator model upgrade. The present 3rd stage of the Project is primarily oriented towards the improvement of the training process for maintenance and operational personnel by means of a development of the Training Support Methodology and Courses (TSMC) to be based on Virtual Reality and enlarged functionality of 3D and process modelling. The TMSC development is based on Russian and International Regulatory Bodies requirements and recommendations. Design, development and creation of a specialised VR-based Training System for RM Maintenance Personnel are very important for the Russian RBMK plants. The main goal is to create a powerful, autonomous VR-based simulator for training technical maintenance personnel on the Refuelling Machine. VR based training is expected to improve the effect of training compared to the current training based on traditional methods using printed documentation. The LNPP management and the Regulatory Bodies supported this goal. The VR-based Training System

  12. THEORETICAL PREDICTION OF TOOL-CHIP CONTACT LENGTH IN ORTHOGONAL METAL MACHINING BY COMPUTER SIMULATION

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A method for determination of tool-chip contact length is theoretically presented in orthogonal metal machining. By using computer simulation and based on the analyses of the elastro-plastic deformation with lagrangian finite element method in the deformation zone,the accumulated representative length of the low layer, the tool-chip contact length of the chip contacting the tool rake are calculated, experimental studies are also carried out with 0.2% carbon steel. It is shown that the tool-chip contact lengths obtained from computer simulation have a good agreement with those of measured values.

  13. Machine-induced Background Simulation Studies for LHC Run 1, Run 2 and HL-LHC

    CERN Document Server

    Kwee-Hinzmann, Regina; Bruce, Roderik; Cerutti, Francesco; Esposito, Luigi Salvatore; Gibson, Stephen; Lechner, Anton; Garcia Morales, Hector; Yin Vallgren, Christina

    2017-01-01

    The study of machine-induced background to the experiments is vital for several reasons. Too much background can be an issue for operation and the difficult part is to judge when exactly “too much” is attained. It is a complex topic as experiments are directly or indirectly affected by conditions all around the LHC ring e.g. collimation settings and vacuum quality. A detailed study of background can also help understanding the machine better to identify potential issues and complemented by dedicated machine tests. Finally such a study is relevant for the experiments to analyse the characteristics of machine background to make sure not to count it into a new physics signal. This report summarises simulation results of three background sources, local beam-gas, beam-halo from the betatron collimation in IR7 and for the first time beam-halo from momentum collimation in IR3. Two of the most dominant sources, local beam-gas and betatron halo, have been systematically studied for LHC Run 1 and Run 2 cases, and ...

  14. Application of Adomian Decomposition for Multi-Machine Power System Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Gurrala, Gurunath [ORNL; Dimitrovski, Aleksandar D [ORNL; Pannala, Sreekanth [ORNL; Simunovic, Srdjan [ORNL; Starke, Michael R [ORNL; Sun, Kai [University of Tennessee (UT)

    2015-01-01

    In this paper, the merits of Adomian Decomposition Method (ADM) have been investigated for the time domain simulation of multi-machine power systems. ADM is an analytical approximation method for the solution of linear, nonlinear, deterministic and stochastic operator equations. It approximates the nonlinearities in the equations using Adomian polynomial series and that can form a rapidly convergent sequence of analytic functions. We apply the ADM approach for simulation of differential algebraic equations representing the detailed multimachine power system. The ADM approach has been applied on the widely used IEEE 3 generator 9 bus system and IEEE 10 generator 39 bus system for 3 fault simulations. In our simulations we found that the ADM approach is faster than the standard trapezoidal time integration method for the comparable accuracy.

  15. Molecular dynamics simulation on a network of workstations using a machine-independent parallel programming language.

    Science.gov (United States)

    Shifman, M A; Windemuth, A; Schulten, K; Miller, P L

    1992-04-01

    Molecular dynamics simulations investigate local and global motion in molecules. Several parallel computing approaches have been taken to attack the most computationally expensive phase of molecular simulations, the evaluation of long range interactions. This paper reviews these approaches and develops a straightforward but effective algorithm using the machine-independent parallel programming language, Linda. The algorithm was run both on a shared memory parallel computer and on a network of high performance Unix workstations. Performance benchmarks were performed on both systems using two proteins. This algorithm offers a portable cost-effective alternative for molecular dynamics simulations. In view of the increasing numbers of networked workstations, this approach could help make molecular dynamics simulations more easily accessible to the research community.

  16. Kinematic Modelling and Control Simulation for 1PS+3TPS Type Hybrid Machine Tool

    Institute of Scientific and Technical Information of China (English)

    FAN Shouwen; WANG Xiaobing; HUANG Hongzhong

    2006-01-01

    A structure scheme for a novel hybrid machine tool (HMT) is proposed in this paper. In the scheme, a 4-DOFs 1PS+3TPS type spatial hybrid mechanism is utilized as main feed mechanism, with assistance of a two direction movable worktable, multi-coordinates NC machining can be realized. In the main feed mechanism, fixed platform is connected with moving platform by three TPS driving links and one PS driving link, one translation DOF and three rotation DOFs can be achieved by it. This type HMT enjoys some advantages over its conventional counterparts:large workspace,good dexterity,etc. Closed form inverse displacement analysis model and inverse kinematic model for main feed mechanism are established. A fuzzy PID control scheme for machining control of HMTs with high tracking precision is proposed aiming at highly nonlinear, tightly coupled and uncertain characteristic of HMTs. Simulation researches for fuzzy PID control of HMTs are carried out. Simulation Results demonstrate the effectiveness and the Robostness of the fuzzy PID controller.

  17. Measurement and Correction of the Fermilab Booster Optics with LOCO*

    CERN Document Server

    Tan, C Y; Triplett, A K; McAteer, M

    2015-01-01

    The optics of the original Booster lacked the ability for full optics correction and it was not until 2009 when new optics corrector packages were installed between gradient magnets that this ability became available. The optics correction method that is chosen is called LOCO (Linear Optics from Closed Orbits) that measures the orbit response from every beam position monitor (BPM) in the ring from every kick of every dipole corrector. The large data set collected allows LOCO to not only calculate the quadrupole and skew quadrupole currents that both reduces beta beatings and corrects coupling, it also finds the dipole kicker strengths, BPM calibrations and their tilts by minimizing the difference between the measured and ideal orbit response of the beam. The corrected optics have been loaded into Booster and it is currently being tested to be eventually used in normal operations.

  18. A Machine Learning Method for the Prediction of Receptor Activation in the Simulation of Synapses

    Science.gov (United States)

    Montes, Jesus; Gomez, Elena; Merchán-Pérez, Angel; DeFelipe, Javier; Peña, Jose-Maria

    2013-01-01

    Chemical synaptic transmission involves the release of a neurotransmitter that diffuses in the extracellular space and interacts with specific receptors located on the postsynaptic membrane. Computer simulation approaches provide fundamental tools for exploring various aspects of the synaptic transmission under different conditions. In particular, Monte Carlo methods can track the stochastic movements of neurotransmitter molecules and their interactions with other discrete molecules, the receptors. However, these methods are computationally expensive, even when used with simplified models, preventing their use in large-scale and multi-scale simulations of complex neuronal systems that may involve large numbers of synaptic connections. We have developed a machine-learning based method that can accurately predict relevant aspects of the behavior of synapses, such as the percentage of open synaptic receptors as a function of time since the release of the neurotransmitter, with considerably lower computational cost compared with the conventional Monte Carlo alternative. The method is designed to learn patterns and general principles from a corpus of previously generated Monte Carlo simulations of synapses covering a wide range of structural and functional characteristics. These patterns are later used as a predictive model of the behavior of synapses under different conditions without the need for additional computationally expensive Monte Carlo simulations. This is performed in five stages: data sampling, fold creation, machine learning, validation and curve fitting. The resulting procedure is accurate, automatic, and it is general enough to predict synapse behavior under experimental conditions that are different to the ones it has been trained on. Since our method efficiently reproduces the results that can be obtained with Monte Carlo simulations at a considerably lower computational cost, it is suitable for the simulation of high numbers of synapses and it is

  19. A machine learning method for the prediction of receptor activation in the simulation of synapses.

    Directory of Open Access Journals (Sweden)

    Jesus Montes

    Full Text Available Chemical synaptic transmission involves the release of a neurotransmitter that diffuses in the extracellular space and interacts with specific receptors located on the postsynaptic membrane. Computer simulation approaches provide fundamental tools for exploring various aspects of the synaptic transmission under different conditions. In particular, Monte Carlo methods can track the stochastic movements of neurotransmitter molecules and their interactions with other discrete molecules, the receptors. However, these methods are computationally expensive, even when used with simplified models, preventing their use in large-scale and multi-scale simulations of complex neuronal systems that may involve large numbers of synaptic connections. We have developed a machine-learning based method that can accurately predict relevant aspects of the behavior of synapses, such as the percentage of open synaptic receptors as a function of time since the release of the neurotransmitter, with considerably lower computational cost compared with the conventional Monte Carlo alternative. The method is designed to learn patterns and general principles from a corpus of previously generated Monte Carlo simulations of synapses covering a wide range of structural and functional characteristics. These patterns are later used as a predictive model of the behavior of synapses under different conditions without the need for additional computationally expensive Monte Carlo simulations. This is performed in five stages: data sampling, fold creation, machine learning, validation and curve fitting. The resulting procedure is accurate, automatic, and it is general enough to predict synapse behavior under experimental conditions that are different to the ones it has been trained on. Since our method efficiently reproduces the results that can be obtained with Monte Carlo simulations at a considerably lower computational cost, it is suitable for the simulation of high numbers of

  20. Loss in Connectivity (LoCo) among regions of the brain reward system in alcohol dependence

    OpenAIRE

    Kuceyeski, Amy; Meyerhoff, Dieter J.; Timothy C. Durazzo; Raj, Ashish

    2012-01-01

    A recently developed measure of structural brain connectivity disruption, the Loss in Connectivity (LoCo), is adapted for studies in alcohol dependence. LoCo uses independent tractography information from young healthy controls to project the location of white matter microstructure abnormalities in alcohol dependent vs. non-dependent individuals onto connected gray matter regions. The LoCo scores are computed from white matter abnormality masks derived at two levels: 1) group-wise differences...

  1. Simulation of rock fragmentation induced by a tunnel boring machine disk cutter

    Directory of Open Access Journals (Sweden)

    Huiyun Li

    2016-05-01

    Full Text Available A constitutive model based on the Johnson–Cook material model and the extended Drucker–Prager strength criterion was implemented in LS-DYNA to simulate the rock failure process induced by a single disk cutter of a tunnel boring machine. The normal, rolling, and side forces were determined by numerical tests. The simulation results showed that the normal and rolling forces increased with increasing penetration while the side force changed little. The normal force also increased under the conditions of confining pressures. The damage region of rock and cutting forces were also obtained by simulation of two disk cutters acting in tandem with different cutting spacings. The optimum ratio of cutter spacing to penetration depth determined from numerical modeling agrees well with that obtained by linear cutting machine tests. The average normal and rolling forces acting on the first cutter are slightly greater than those acting on the second when the cutting disk spacing is relatively small. The numerical modeling was verified to accurately capture the fragmentation of rock induced by disk cutter.

  2. SIMULATION BASED PLANNING FOR DESIGN OF WASHING MACHINE USING H/W & S/W CO DESIGN

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar Garg

    2010-11-01

    Full Text Available A simulator is designed and developed or helping embedded system development team to plan their time schedule, work flow etc. and distribute human resources and their efforts over various phasesof washing machine development. The simulator helps in identifying development phases of washing machine for successful operations of overall system. The development process of washing machine has beendone in a cost effective way by planning and managing and simulating the system. The simulator gives the results in form of critical and near-critical phases while considering the rest of phases as concurrent development activities. The simulator has been a handytool for engineers in developing the system in an optimal manner. Hardware/Software Codesign approach in which both hardware and software designers’ work together to develop a system is used inthis work.

  3. Simulation of Digital Control Computer of Nuclear Power Plant Based on Virtual Machine Technology

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Xue Yan; Li, Shu; Li, Qing [China Nuclear Power Operation Technology Co., Wuhan (China)

    2011-08-15

    Based on analyzing DCC (Digital Control Computer) instruction sets, memory map, display controllers and I/O system, virtual machine of DCC (abbr. VM DCC) has been developed. The executive and control programs, same as running on NPP (Nuclear Power Plant) unit's DCC, can run on the VM DCC smoothly and get same control results. Dual VM DCC system has been successfully applied in NPP FSS(Full Scope Simulator) training. It not only improves FSS's fidelity but also makes maintaining easier.

  4. Real-Time Simulation and Analysis of the Induction Machine Performances Operating at Flux Constant

    Directory of Open Access Journals (Sweden)

    Aziz Derouich

    2014-05-01

    Full Text Available In this paper, we are interested, in a first time, at the study and the implementation of a V/f control for induction machine in real time. After, We are attached to a comparison of the results by simulation and experiment for, speed responses, flux and currents of the real machine, with a DSPACE card and model established by classical identification (Direct Current test , blocked-rotor test, no-load test , synchronous test, to ensure the validity of the established model. The scalar controlled induction motor allows operation of the motor with the maximum torque by simultaneous action on the frequency and amplitude of the stator voltage, with conservation of the ratio V/f. Speed reference imposes a frequency at the inverter supplying the voltages needed to power the motor, which determines the speed of rotation. The maximum torque of the machine is proportional to the square of the supply voltage and inversely proportional to the frequency voltage. So, Keep V/f constant implies a operating with maximum constant torque. The results obtained for the rotor flux and the stator currents are especially satisfactory steady.

  5. Monte Carlo simulation of a multi-leaf collimator design for telecobalt machine using BEAMnrc code

    Directory of Open Access Journals (Sweden)

    Ayyangar Komanduri

    2010-01-01

    Full Text Available This investigation aims to design a practical multi-leaf collimator (MLC system for the cobalt teletherapy machine and check its radiation properties using the Monte Carlo (MC method. The cobalt machine was modeled using the BEAMnrc Omega-Beam MC system, which could be freely downloaded from the website of the National Research Council (NRC, Canada. Comparison with standard depth dose data tables and the theoretically modeled beam showed good agreement within 2%. An MLC design with low melting point alloy (LMPA was tested for leakage properties of leaves. The LMPA leaves with a width of 7 mm and height of 6 cm, with tongue and groove of size 2 mm wide by 4 cm height, produced only 4% extra leakage compared to 10 cm height tungsten leaves. With finite 60 Co source size, the interleaf leakage was insignificant. This analysis helped to design a prototype MLC as an accessory mount on a cobalt machine. The complete details of the simulation process and analysis of results are discussed.

  6. A data-based technique for monitoring of wound rotor induction machines: A simulation study

    Directory of Open Access Journals (Sweden)

    Fouzi Harrou

    2016-09-01

    Full Text Available Detecting faults induction machines is crucial for a safe operation of these machines. The aim of this paper is to present a statistical fault detection methodology for the detection of faults in three-phase wound rotor induction machines (WRIM. The proposed fault detection approach is based on the use of principal components analysis (PCA. However, conventional PCA-based detection indices, such as the T2 and the Q statistics, are not well suited to detect small faults because these indices only use information from the most recent available samples. Detection of small faults is one of the most crucial and challenging tasks in the area of fault detection and diagnosis. In this paper, a new statistical system monitoring strategy is proposed for detecting changes resulting from small shifts in several variables associated with WRIM. The proposed approach combines modeling using PCA modeling with the exponentially weighted moving average (EWMA control scheme. In the proposed approach, EWMA control scheme is applied on the ignored principal components to detect the presence of faults. The performance of the proposed method is compared with those of the traditional PCA-based fault detection indices. The simulation results clearly show the effectiveness of the proposed method over the conventional ones, especially in the presence of faults with small magnitudes.

  7. A data-based technique for monitoring of wound rotor induction machines: A simulation study

    KAUST Repository

    Harrou, Fouzi

    2016-05-09

    Detecting faults induction machines is crucial for a safe operation of these machines. The aim of this paper is to present a statistical fault detection methodology for the detection of faults in three-phase wound rotor induction machines (WRIM). The proposed fault detection approach is based on the use of principal components analysis (PCA). However, conventional PCA-based detection indices, such as the T2T2 and the Q statistics, are not well suited to detect small faults because these indices only use information from the most recent available samples. Detection of small faults is one of the most crucial and challenging tasks in the area of fault detection and diagnosis. In this paper, a new statistical system monitoring strategy is proposed for detecting changes resulting from small shifts in several variables associated with WRIM. The proposed approach combines modeling using PCA modeling with the exponentially weighted moving average (EWMA) control scheme. In the proposed approach, EWMA control scheme is applied on the ignored principal components to detect the presence of faults. The performance of the proposed method is compared with those of the traditional PCA-based fault detection indices. The simulation results clearly show the effectiveness of the proposed method over the conventional ones, especially in the presence of faults with small magnitudes.

  8. A Case Study Regarding Influence of Solvers in Matlab/Simulink for Induction Machine Model in Wind Turbine Simulations

    DEFF Research Database (Denmark)

    Iov, F.; Blaabjerg, Frede; Hansen, A.D.

    2002-01-01

    , transformer and grid. These subsystems are described by differential equations with different simulation steps. The electrical generator and the power converter need the smallest simulation step and therefore, these blocks decide the simulation speed. This paper present important aspects regarding...... the different implementations of induction machine model, influence of the solvers from Simulink and how the simulation speed can be increase for a wind turbine....

  9. Modeling and Simulation of Process-Machine Interaction in Grinding of Cemented Carbide Indexable Inserts

    National Research Council Canada - National Science Library

    Feng, Wei; Yao, Bin; Chen, BinQiang; Zhang, DongSheng; Zhang, XiangLei; Shen, ZhiHuang

    2015-01-01

      Interaction of process and machine in grinding of hard and brittle materials such as cemented carbide may cause dynamic instability of the machining process resulting in machining errors and a decrease in productivity...

  10. Research on the effects of machining-induced subsurface damages on mono-crystalline silicon via molecular dynamics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Hongwei, E-mail: hwzhao@jlu.edu.cn [College of Mechanical Science and Engineering, Jilin University, 5988 Renmin Street, Changchun, Jilin 130025 (China); Shi Chengli; Zhang Peng; Zhang Lin; Huang Hu; Yan Jiwang [College of Mechanical Science and Engineering, Jilin University, 5988 Renmin Street, Changchun, Jilin 130025 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer MD simulations of nano-cutting process are carried out to obtain machining-induced subsurface with diamond cutting tools. Black-Right-Pointing-Pointer After cutting, the crystal lattice reconstructed and led to the formation of the machined surface. Black-Right-Pointing-Pointer The mechanical properties of the pristine and machining-induced subsurface Si are studied by means of nanoindentation. Black-Right-Pointing-Pointer Nanoindentation results show that the hardness of the machined surface was smaller than mono-crystalline Si. - Abstract: Nanoindentation simulation via molecular dynamic (MD) method was carried out to investigate the characteristics of machining-induced subsurface damage of mono-crystalline silicon with a spherical diamond indenter. In this study, MD simulations of nano-cutting process were carried out firstly to cut through the specimen's surface with diamond cutting tools of different edge radius of 0 nm, 3 nm and 5 nm respectively. Then, MD simulation of nanoindentation on the machined surface was carried out. Tersoff potential was used to model the interaction of Si atoms, and the interaction between Si and C atoms was modeled by Morse potential. Simulational results indicate that during cutting process, the specimen undergo plastic deformation and phase transformation. After cutting process, the crystal lattice reconstructs and the residual amorphous layers lead to the formation of the machined surface. Nanoindentation results show that the hardness of the machined surface is smaller than mono-crystalline Si. So in order to get accurate properties of the pristine silicon or other semiconductor materials via experiments, the amorphous phase should be completely removed or it would influence the mechanical properties of the pristine materials.

  11. An Intelligent and Interactive Simulation and Tutoring Environment for Exploring and Learning Simple Machines

    Science.gov (United States)

    Myneni, Lakshman Sundeep

    Students in middle school science classes have difficulty mastering physics concepts such as energy and work, taught in the context of simple machines. Moreover, students' naive conceptions of physics often remain unchanged after completing a science class. To address this problem, I developed an intelligent tutoring system, called the Virtual Physics System (ViPS), which coaches students through problem solving with one class of simple machines, pulley systems. The tutor uses a unique cognitive based approach to teaching simple machines, and includes innovations in three areas. (1) It employs a teaching strategy that focuses on highlighting links among concepts of the domain that are essential for conceptual understanding yet are seldom learned by students. (2) Concepts are taught through a combination of effective human tutoring techniques (e.g., hinting) and simulations. (3) For each student, the system identifies which misconceptions he or she has, from a common set of student misconceptions gathered from domain experts, and tailors tutoring to match the correct line of scientific reasoning regarding the misconceptions. ViPS was implemented as a platform on which students can design and simulate pulley system experiments, integrated with a constraint-based tutor that intervenes when students make errors during problem solving to teach them and to help them. ViPS has a web-based client-server architecture, and has been implemented using Java technologies. ViPS is different from existing physics simulations and tutoring systems due to several original features. (1). It is the first system to integrate a simulation based virtual experimentation platform with an intelligent tutoring component. (2) It uses a novel approach, based on Bayesian networks, to help students construct correct pulley systems for experimental simulation. (3) It identifies student misconceptions based on a novel decision tree applied to student pretest scores, and tailors tutoring to

  12. 3D Finite Element Simulation of Tunnel Boring Machine Construction Processes in Deep Water Conveyance Tunnel

    Institute of Scientific and Technical Information of China (English)

    ZHONG Denghua; TONG Dawei

    2009-01-01

    Applying stiffness migration method, a 3D finite element mechanical model is established to simulate the excavation and advance processes. By using 3D nonlinear finite element method, the tunnel boring machine (TBM) excavation process is dynamically simulated to analyze the stress and strain field status of surrounding rock and segment. The maximum tensile stress of segment ring caused by tunnel construction mainly lies in arch bottom and presents zonal distribution. The stress increases slightly and limitedly in the course of excavation. The maxi-mum and minimum displacements of segment, manifesting as zonal distribution, distribute in arch bottom and vault respectively. The displacements slightly increase with the advance of TBM and gradually tend to stability.

  13. Simulation of fluid flow inside a continuous slab-casting machine

    Science.gov (United States)

    Thomas, B. G.; Mika, L. J.; Najjar, F. M.

    1990-04-01

    A finite element model has been developed and applied to compute the fluid flow distribution inside the shell in the mold region of a continuous, steel slab-casting machine. The model was produced with the commercial program FIDAP, which allows this nonlinear, highly turbulent problem to be simulated using the K- ɛ turbulence model. It consists of separate two-dimensional (2-D) models of the nozzle and a section through the mold, facing the broad face. The predicted flow patterns and velocity fields show reasonable agreement with experimental observations and measurements conducted using a transparent plastic water model. The effects of nozzle angle, casting speed, mold width, and turbulence simulation parameters on the flow pattern have been investigated. The overall flow field is relatively insensitive to process parameters.

  14. RESEARCH INTO VALVE-ENGINE TRANSDUCERS OF BRUSHLESS SYNCHRONOUS AND ASYNCHRONIZED MACHINES IN A CIRCUIT SIMULATION SYSTEM.

    Directory of Open Access Journals (Sweden)

    A.M. Galynovskiy

    2013-10-01

    Full Text Available Designing features for valve-engine transducers of brushless synchronous and asynchronized machines are described. Global analysis of research results on the transducer models in a MicroCap circuit simulation system is made, recommendations on the simulation system application in both scientific research and educational process given.

  15. Integration of an intelligent systems behavior simulator and a scalable soldier-machine interface

    Science.gov (United States)

    Johnson, Tony; Manteuffel, Chris; Brewster, Benjamin; Tierney, Terry

    2007-04-01

    As the Army's Future Combat Systems (FCS) introduce emerging technologies and new force structures to the battlefield, soldiers will increasingly face new challenges in workload management. The next generation warfighter will be responsible for effectively managing robotic assets in addition to performing other missions. Studies of future battlefield operational scenarios involving the use of automation, including the specification of existing and proposed technologies, will provide significant insight into potential problem areas regarding soldier workload. The US Army Tank Automotive Research, Development, and Engineering Center (TARDEC) is currently executing an Army technology objective program to analyze and evaluate the effect of automated technologies and their associated control devices with respect to soldier workload. The Human-Robotic Interface (HRI) Intelligent Systems Behavior Simulator (ISBS) is a human performance measurement simulation system that allows modelers to develop constructive simulations of military scenarios with various deployments of interface technologies in order to evaluate operator effectiveness. One such interface is TARDEC's Scalable Soldier-Machine Interface (SMI). The scalable SMI provides a configurable machine interface application that is capable of adapting to several hardware platforms by recognizing the physical space limitations of the display device. This paper describes the integration of the ISBS and Scalable SMI applications, which will ultimately benefit both systems. The ISBS will be able to use the Scalable SMI to visualize the behaviors of virtual soldiers performing HRI tasks, such as route planning, and the scalable SMI will benefit from stimuli provided by the ISBS simulation environment. The paper describes the background of each system and details of the system integration approach.

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

    Science.gov (United States)

    Plank, Harald

    2015-02-06

    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.

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

    Science.gov (United States)

    Plank, Harald

    2015-02-01

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

  18. Melanoma targeting with the loco-regional chemotherapeutic, Melphalan: From cell death to immunotherapeutic efficacy.

    Science.gov (United States)

    Dudek-Perić, Aleksandra Maria; Gołąb, Jakub; Garg, Abhishek D; Agostinis, Patrizia

    2015-12-01

    All immunoregulatory chemotherapeutics are chiefly applied in a systemic setting for anticancer therapy. However, immune responses following loco-regional application of chemotherapy may differ from those after systemic application. We recently found that Melphalan, a prototypical loco-regionally applied chemotherapeutic agent, exhibits the ability to increase the immunogenicity of dying melanoma cells.

  19. "In Loco Parentis" Revisited and Commercial Speech on Campus. ASHE 1987 Annual Meeting Paper.

    Science.gov (United States)

    Hobbs, Walter C.

    The applicability of "in loco parentis" and the issue of commercial speech (e.g. sales pitches and advertising) on campus are discussed. While in previous years the principle of in loco parentis allowed colleges to dicate the behavior of its students, colleges must now take reasonable steps to guarantee the physical safety of students.…

  20. Feed drive modelling for the simulation of tool path tracking in multi-axis High Speed Machining

    CERN Document Server

    Prévost, David; Lartigue, Claire; Dumur, Didier

    2011-01-01

    Within the context of High Speed Machining, it is essential to manage the trajectory generation to achieve both high surface quality and high productivity. As feed drives are one part of the set Machine tool - Numerical Controller, it is necessary to improve their performances to optimize feed drive dynamics during trajectory follow up. Hence, this paper deals with the modelling of the feed drive in the case of multi axis machining. This model can be used for the simulation of axis dynamics and tool-path tracking to tune parameters and optimize new frameworks of command strategies. A procedure of identification based on modern NC capabilities is presented and applied to industrial HSM centres. Efficiency of this modelling is assessed by experimental verifications on various representative trajectories. After implementing a Generalized Predictive Control, reliable simulations are performed thanks to the model. These simulations can then be used to tune parameters of this new framework according to the tool-pat...

  1. Estimating the Mass of the Local Group using Machine Learning Applied to Numerical Simulations

    CERN Document Server

    McLeod, Michael; Lahav, Ofer; Hoffman, Yehuda

    2016-01-01

    We revisit the estimation of the combined mass of the Milky Way and Andromeda (M31), which dominate the mass of the Local Group. We make use of an ensemble of 30,190 halo pairs from the Small MultiDark simulation, assuming a $\\Lambda$CDM (Cosmological Constant with Cold Dark Matter) cosmology, to investigate the relationship between the bound mass and parameters characterising the orbit of the binary and their local environment with the aid of machine learning methods (artificial neural networks, ANN). Results from the ANN are most successful when information about the velocity shear is provided, which demonstrates the flexibility of machine learning to model physical phenomena and readily incorporate new information as it becomes available. The resulting estimate for the Local Group mass, when shear information is included, is $4.9 \\times 10^{12} M_\\odot$, with an error of $\\pm0.8 \\times 10^{12} M_\\odot$ from the 68% uncertainty in observables, and a 68% confidence interval of $^{+1.3}_{-1.4} \\times 10^{12}M...

  2. Numerical Modeling of Dual-Pulse Shock Test Machine for Simulating Underwater Explosion Shock Loads on Warship Equipments

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-yi; WANG Gong-xian; WANG Yu

    2009-01-01

    In order to qualify shock resistance performance of shipboard equipments and simulate real underwater explosion environment, a novel dual-puise shock test machine is proposed. The new machine will increase testing capability and meet special shock testing requirement. Two key parts of the machine, the velocity generator and the shock pulse regulator, play an important role in producing the positive acceleration pulse and the succeeding negative acceleration pulse, respectively. The generated dual-pulse shock for test articles is in conformity with an anti-shock test specification. Based on the impact theory, a nonlinear dynamic model of the hydraulically-actuated test machine is established with thorough analysis on its mechanism that involves conversion of gas potential energy and dissipation of kinetic energy. Simulation results have demonstrated that the proposed machine is able to produce a double-pulse acceleration shock in the time domain or a desired shock response spectrum in the frequency domain, which sets up a base for the construction of the machine.

  3. A numerical study of ultraprecision machining of monocrystalline silicon with laser nano-structured diamond tools by atomistic simulation

    Science.gov (United States)

    Dai, Houfu; Chen, Genyu; Zhou, Cong; Fang, Qihong; Fei, Xinjiang

    2017-01-01

    Three-dimension molecular dynamics (MD) simulations is employed to investigate the ultraprecision machining of single crystal silicon with structured nanoscale diamond tool fabricated by laser. The advantages and disadvantages of diamond machining using structured tools are discussed in comparison with those of using non-structured tools. The von Mises stress distribution, hydrostatic stress distribution, atomic displacement, stress, the radial distribution function, cutting forces, frictional coefficient, subsurface temperature and potential energy during the nanometric machining process are studied. A theoretical analysis model is also established to investigate the subsurface damage mechanism by analyzing the distribution of residual stress during the nanoscale machining process. The results show that a structured nanoscale tool in machining brittle material silicon causes a smaller hydrostatic stress, a less compressive normal stress σxx and σyy , a lower temperature and a smaller cutting force. However, the structured nanoscale tool machining results in smaller chip volume and more beta-silicon phase. Besides, the friction coefficient for tool with V-shape groove is smaller than those for non-structured tools and other structured nanoscale tools. This means that the tool with V-shape groove can reduce the resistance to cutting during the nanoscale machining process. In addition, the results also point out that the potential energy of subsurface atoms and the number of other atoms for pyramid-structured tool are much smaller than those of using non-structured tools and other structured nanoscale tools.

  4. Sedimentation survey of Lago Loco, Puerto Rico, March 2000

    Science.gov (United States)

    Soler-López, Luis R.

    2002-01-01

    Lago Loco, a small reservoir property of the Puerto Rico Electric Power Authority and part of the Southwestern Puerto Rico Project, has lost 64 percent of its original storage capacity. In 1951, the original storage capacity was about 2.40 million cubic meters, decreasing to 1.43 million cubic meters in 1986 and to 0.87 million cubic meters in March 2000. The storage loss or longterm sedimentation rate increased from 27,714 cubic meters per year from the period of 1951 to 1986 to 31,224 cubic meters per year for the period of 1951 to 2000. This represents a capacity loss of about 1.1 percent per year for the period of 1951 to 1986 and 1.3 percent per year for 1951 to 2000. The trapping efficiency of the reservoir was about 92 percent in 1951, decreasing to about 87 percent in 1986, and to about 80 percent in March 2000. The sediment yield of the net sediment- contributing drainage area increased from 1,504 megagrams per square kilometer per year between 1951 and 1986 to 1,774 megagrams per square kilometer per year between 1951 and 2000, or about 18 percent. At the current sedimentation rate of the reservoir, the life expectancy of Lago Loco is about 28 more years or until the year 2028.

  5. Photometric Properties of Low-Redshift Galaxy Clusters (LOCOS)

    CERN Document Server

    López-Cruz, O

    2000-01-01

    A comprehensive multicolor survey was undertaken to investigate global optical properties of Abell clusters of galaxies. This survey was christened the "Low-Redshift Cluster Optical Survey" (LOCOS). LOCOS was devised to search for patterns of galaxy evolution induced by the environment. The generated data base contains accurate deep CCD photometric measurements (Kron-Cousins R,,B and I) for a sample of 46 low-redshift (0.04 <= z <= 0.18) Abell clusters. This is one of the few large surveys that included the contribution due to dwarf galaxies (about 5.5 mag deeper than the R characteristic magnitude (M*); Ho=50 km/s/Mpc, qo=0). Due to space restrictions only the main results concerning the variations at the bright-end of the luminosity function (LF) are presented here. Other results are presented elsewhere (Lopez-Cruz & Yee 2000a,b). We have detected clear variations at both the bright end and the faint end of the LF. The nature of the variations at the bright end revealed that poor cD clusters have ...

  6. Parallel Sparse Matrix Solver on the GPU Applied to Simulation of Electrical Machines

    CERN Document Server

    Rodrigues, Antonio Wendell De Oliveira; Menach, Yvonnick Le; Dekeyser, Jean-Luc

    2010-01-01

    Nowadays, several industrial applications are being ported to parallel architectures. In fact, these platforms allow acquire more performance for system modelling and simulation. In the electric machines area, there are many problems which need speed-up on their solution. This paper examines the parallelism of sparse matrix solver on the graphics processors. More specifically, we implement the conjugate gradient technique with input matrix stored in CSR, and Symmetric CSR and CSC formats. This method is one of the most efficient iterative methods available for solving the finite-element basis functions of Maxwell's equations. The GPU (Graphics Processing Unit), which is used for its implementation, provides mechanisms to parallel the algorithm. Thus, it increases significantly the computation speed in relation to serial code on CPU based systems.

  7. Simulation modeling and tracing optimal trajectory of robotic mining machine effector

    Science.gov (United States)

    Fryanov, VN; Pavlova, LD

    2017-02-01

    Within the framework of the robotic coal mine design for deep-level coal beds with the high gas content in the seismically active areas in the southern Kuzbass, the motion path parameters for an effector of a robotic mining machine are evaluated. The simulation model is meant for selection of minimum energy-based optimum trajectory for the robot effector, calculation of stresses and strains in a coal bed in a variable perimeter shortwall in the course of coal extraction, determination of coordinates of a coal bed edge area with the maximum disintegration of coal, and for choice of direction of the robot effector to get in contact with the mentioned area and to break coal at the minimum energy input. It is suggested to use the model in the engineering of the robot intelligence.

  8. MCNP Simulation to Hard X-Ray Emission of KSU Dense Plasma Focus Machine

    CERN Document Server

    Mohamed, Amgad E

    2015-01-01

    The MCNP program used to simulate the hard x-ray emission from KSU dense plasma focus device, an electron beam spectrum of maximum energy 100 keV was used to hit anode target. The bremsstrahlung radiation was measured using the F2 tally functions on the chamber walls and on a virtual sphere surrounding the machine, the radiation spectrum was recorded for various anode materials like tungsten, stainless steel and molybdenum. It was found that tungsten gives the best and the most intense radiation for the same electron beam. An aluminum filter of thickness 2mm and 4mm was used to cutoff the lower energy band from the x-ray spectrum. It was found that the filters achieved the mission and there is no distinct difference in between.

  9. Modelling and simulation for table tennis referee regulation based on finite state machine.

    Science.gov (United States)

    Cui, Jianjiang; Liu, Zixuan; Xu, Long

    2017-10-01

    As referee's decisions are made artificially in traditional table tennis matches, many factors in a match, such as fatigue and subjective tendency, may lead to unjust decision. Based on finite state machine (FSM), this paper presents a model for table tennis referee regulation to substitute manual decisions. In this model, the trajectory of the ball is recorded through a binocular visual system while the complete rules extracted from the International Table Tennis Federation (ITTF) rules are described based on FSM. The final decision for the competition is made based on expert system theory. Simulation result shows that the proposed model has high accuracy, and can be generalised to other similar games such as badminton, volleyball, etc.

  10. Finger milling-cutter CNC generating hypoid pinion tooth surfaces based on modified-roll method and machining simulation

    Science.gov (United States)

    Li, Genggeng; Deng, Xiaozhong; Wei, Bingyang; Lei, Baozhen

    2011-05-01

    The two coordinate systems of cradle-type hypoid generator and free-form CNC machine tool by application disc milling-cutter to generate hypoid pinion tooth surfaces based on the modified-roll method were set up, respectively, and transformation principle and method for machine-tool settings between the two coordinate systems was studied. It was presented that finger milling-cutter was mounted on imagined disc milling-cutter and its motion was controlled directly by CNC shafts to replace disc milling-cutter blades effective cutting motion. Finger milling-cutter generation accomplished by ordered circular interpolation was determined, and interpolation center, starting and ending were worked out. Finally, a hypoid pinion was virtually machined by using CNC machining simulation software VERICUT.

  11. Taxi Time Prediction at Charlotte Airport Using Fast-Time Simulation and Machine Learning Techniques

    Science.gov (United States)

    Lee, Hanbong

    2016-01-01

    Accurate taxi time prediction is required for enabling efficient runway scheduling that can increase runway throughput and reduce taxi times and fuel consumptions on the airport surface. Currently NASA and American Airlines are jointly developing a decision-support tool called Spot and Runway Departure Advisor (SARDA) that assists airport ramp controllers to make gate pushback decisions and improve the overall efficiency of airport surface traffic. In this presentation, we propose to use Linear Optimized Sequencing (LINOS), a discrete-event fast-time simulation tool, to predict taxi times and provide the estimates to the runway scheduler in real-time airport operations. To assess its prediction accuracy, we also introduce a data-driven analytical method using machine learning techniques. These two taxi time prediction methods are evaluated with actual taxi time data obtained from the SARDA human-in-the-loop (HITL) simulation for Charlotte Douglas International Airport (CLT) using various performance measurement metrics. Based on the taxi time prediction results, we also discuss how the prediction accuracy can be affected by the operational complexity at this airport and how we can improve the fast time simulation model before implementing it with an airport scheduling algorithm in a real-time environment.

  12. Numerical Simulations of Two-Phase Flow in a Self-Aerated Flotation Machine and Kinetics Modeling

    KAUST Repository

    Fayed, Hassan E.

    2015-03-30

    A new boundary condition treatment has been devised for two-phase flow numerical simulations in a self-aerated minerals flotation machine and applied to a Wemco 0.8 m3 pilot cell. Airflow rate is not specified a priori but is predicted by the simulations as well as power consumption. Time-dependent simulations of two-phase flow in flotation machines are essential to understanding flow behavior and physics in self-aerated machines such as the Wemco machines. In this paper, simulations have been conducted for three different uniform bubble sizes (db = 0.5, 0.7 and 1.0 mm) to study the effects of bubble size on air holdup and hydrodynamics in Wemco pilot cells. Moreover, a computational fluid dynamics (CFD)-based flotation model has been developed to predict the pulp recovery rate of minerals from a flotation cell for different bubble sizes, different particle sizes and particle size distribution. The model uses a first-order rate equation, where models for probabilities of collision, adhesion and stabilization and collisions frequency estimated by Zaitchik-2010 model are used for the calculation of rate constant. Spatial distributions of dissipation rate and air volume fraction (also called void fraction) determined by the two-phase simulations are the input for the flotation kinetics model. The average pulp recovery rate has been calculated locally for different uniform bubble and particle diameters. The CFD-based flotation kinetics model is also used to predict pulp recovery rate in the presence of particle size distribution. Particle number density pdf and the data generated for single particle size are used to compute the recovery rate for a specific mean particle diameter. Our computational model gives a figure of merit for the recovery rate of a flotation machine, and as such can be used to assess incremental design improvements as well as design of new machines.

  13. A discrete event simulation design for block-based maintenance planning under random machine usage

    NARCIS (Netherlands)

    de Jonge, Bram

    2015-01-01

    Existing research on block-based preventive maintenance planning generally assumes that machines are either used continuously, or that times until failure do not depend on the actual usage of machines. In practice, however, it is often more realistic to assume that machines are not used continuously

  14. Three-Dimensional Finite Element Based Numerical Simulation of Machining of Thin-Wall Components with Varying Wall Constraints

    Science.gov (United States)

    Joshi, Shrikrishna Nandkishor; Bolar, Gururaj

    2017-06-01

    Control of part deflection and deformation during machining of low rigidity thin-wall components is an important aspect in the manufacture of desired quality products. This paper presents a comparative study on the effect of geometry constraints on the product quality during machining of thin-wall components made of an aerospace alloy aluminum 2024-T351. Three-dimensional nonlinear finite element (FE) based simulations of machining of thin-wall parts were carried out by considering three variations in the wall constraint viz. free wall, wall constrained at one end, and wall with constraints at both the ends. Lagrangian formulation based transient FE model has been developed to simulate the interaction between the workpiece and helical milling cutter. Johnson-Cook material and damage model were adopted to account for material behavior during machining process; damage initiation and chip separation. A modified Coulomb friction model was employed to define the contact between the cutting tool and the workpiece. The numerical model was validated with experimental results and found to be in good agreement. Based on the simulation results it was noted that deflection and deformation were maximum in the thin-wall constrained at one end in comparison with those obtained in other cases. It was noted that three dimensional finite element simulations help in a better way to predict the product quality during precision manufacturing of thin-wall components.

  15. Statistical analysis of simulation-generated time series : Systolic vs. semi-systolic correlation on the Connection Machine

    NARCIS (Netherlands)

    Dontje, T.; Lippert, Th.; Petkov, N.; Schilling, K.

    1992-01-01

    Autocorrelation becomes an increasingly important tool to verify improvements in the state of the simulational art in Latice Gauge Theory. Semi-systolic and full-systolic algorithms are presented which are intensively used for correlation computations on the Connection Machine CM-2. The semi-systoli

  16. Statistical analysis of simulation-generated time series : Systolic vs. semi-systolic correlation on the Connection Machine

    NARCIS (Netherlands)

    Dontje, T.; Lippert, Th.; Petkov, N.; Schilling, K.

    1992-01-01

    Autocorrelation becomes an increasingly important tool to verify improvements in the state of the simulational art in Latice Gauge Theory. Semi-systolic and full-systolic algorithms are presented which are intensively used for correlation computations on the Connection Machine CM-2. The

  17. Simulating the effect of SFCL on limiting the internal fault of synchronous machine

    Energy Technology Data Exchange (ETDEWEB)

    Kheirizad, I [Islamic Republic of Iran Broadcasting, Tehran (Iran, Islamic Republic of); Varahram, M H [Ministry of Science, Research and Technology, Tehran (Iran, Islamic Republic of); Jahed-Motlagh, M R [Azad University of Science and Research, Tehran (Iran, Islamic Republic of); Rahnema, M; Mohammadi, A [Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)], E-mail: hadi_varahram@yahoo.com

    2008-02-01

    In this paper, we have modelled a synchronous generator with internal one phase to ground fault and then the performance of this machine with internal one phase to ground fault have been analyzed. The results show that if the faults occur in vicinity of machine's terminal, then we would have serious damages. To protect the machine from this kind of faults we have suggested integrating a SFCL (superconducting fault current limiter) into the machine's model. The results show that the fault currents in this case will reduce considerably without influencing the normal operation of the machine.

  18. Simulation and Experimental Testing of an Actuator for a Fast Switching On-Off Valve Suitable to Efficient Displacement Machines

    DEFF Research Database (Denmark)

    Roemer, Daniel Beck; Johansen, Per; Bech, Michael Møller

    2014-01-01

    for the valve design process. In this paper simulation of such fast switching valve is presented and the transient actuator performance is experimentally validated against transient Finite Element Analysis (FEA). Models predict a switching time of approximately 1ms for the valve and a pressure loss of 0.5 bar......Digital Displacement (DD) fluid power machines are upcoming technology, improving the efficiency compared to traditional variable displacement machines, especially at low displacements where currently available fluid power pumps/motors suffer from mediocre efficiency. This efficiency improvement...

  19. Distributed processing (DP) based e-beam lithography simulation with long range correction algorithm in e-beam machine

    Science.gov (United States)

    Ki, Won-Tai; Choi, Ji-Hyeon; Kim, Byung-Gook; Woo, Sang-Gyun; Cho, Han-Ku

    2008-05-01

    As the design rule with wafer process is getting smaller down below 50nm node, the specification of CDs on a mask is getting more tightened. Therefore, more tight and accurate E-Beam Lithography simulation is highly required in these days. However, in reality most of E-Beam simulation cases, there is a trade-off relationship between the accuracy and the simulation speed. Moreover, the necessity of full chip based simulation has been increasing in order to estimate more accurate mask CDs based on real process condition. Therefore, without consideration of long range correction algorithm such as fogging effect and loading effect correction in E-beam machine, it would be impossible and meaningless to pursue the full chip based simulation. In this paper, we introduce a breakthrough method to overcome the obstacles of E-Beam simulation. In-house E-beam simulator, ELIS (E-beam LIthography Simulator), has been upgraded to solve these problems. First, DP (Distributed Processing) strategy was applied to improve calculation speed. Secondly, the long range correction algorithm of E-beam machine was also applied to compute intensity of exposure on a full chip based (Mask). Finally, ELIS-DP has been evaluated possibility of expecting or analyzing CDs on full chip base.

  20. Analog models of computations \\& Effective Church Turing Thesis: Efficient simulation of Turing machines by the General Purpose Analog Computer

    CERN Document Server

    Pouly, Amaury; Graça, Daniel S

    2012-01-01

    \\emph{Are analog models of computations more powerful than classical models of computations?} From a series of recent papers, it is now clear that many realistic analog models of computations are provably equivalent to classical digital models of computations from a \\emph{computability} point of view. Take, for example, the probably most realistic model of analog computation, the General Purpose Analog Computer (GPAC) model from Claude Shannon, a model for Differential Analyzers, which are analog machines used from 1930s to early 1960s to solve various problems. It is now known that functions computable by Turing machines are provably exactly those that are computable by GPAC. This paper is about next step: understanding if this equivalence also holds at the \\emph{complexity} level. In this paper we show that the realistic models of analog computation -- namely the General Purpose Analog Computer (GPAC) -- can simulate Turing machines in a computationally efficient manner. More concretely we show that, modulo...

  1. Simulating and Detecting Radiation-Induced Errors for Onboard Machine Learning

    Science.gov (United States)

    Wagstaff, Kiri L.; Bornstein, Benjamin; Granat, Robert; Tang, Benyang; Turmon, Michael

    2009-01-01

    Spacecraft processors and memory are subjected to high radiation doses and therefore employ radiation-hardened components. However, these components are orders of magnitude more expensive than typical desktop components, and they lag years behind in terms of speed and size. We have integrated algorithm-based fault tolerance (ABFT) methods into onboard data analysis algorithms to detect radiation-induced errors, which ultimately may permit the use of spacecraft memory that need not be fully hardened, reducing cost and increasing capability at the same time. We have also developed a lightweight software radiation simulator, BITFLIPS, that permits evaluation of error detection strategies in a controlled fashion, including the specification of the radiation rate and selective exposure of individual data structures. Using BITFLIPS, we evaluated our error detection methods when using a support vector machine to analyze data collected by the Mars Odyssey spacecraft. We found ABFT error detection for matrix multiplication is very successful, while error detection for Gaussian kernel computation still has room for improvement.

  2. Simulating and Detecting Radiation-Induced Errors for Onboard Machine Learning

    Science.gov (United States)

    Wagstaff, Kiri L.; Bornstein, Benjamin; Granat, Robert; Tang, Benyang; Turmon, Michael

    2009-01-01

    Spacecraft processors and memory are subjected to high radiation doses and therefore employ radiation-hardened components. However, these components are orders of magnitude more expensive than typical desktop components, and they lag years behind in terms of speed and size. We have integrated algorithm-based fault tolerance (ABFT) methods into onboard data analysis algorithms to detect radiation-induced errors, which ultimately may permit the use of spacecraft memory that need not be fully hardened, reducing cost and increasing capability at the same time. We have also developed a lightweight software radiation simulator, BITFLIPS, that permits evaluation of error detection strategies in a controlled fashion, including the specification of the radiation rate and selective exposure of individual data structures. Using BITFLIPS, we evaluated our error detection methods when using a support vector machine to analyze data collected by the Mars Odyssey spacecraft. We found ABFT error detection for matrix multiplication is very successful, while error detection for Gaussian kernel computation still has room for improvement.

  3. Evolution of Responsibility: From "In Loco Parentis" to "Ad Meliora Vertamur"

    Science.gov (United States)

    Bowden, Randall

    2007-01-01

    This paper provides a perspective of the evolution of the doctrine of "in loco parentis" to contract law to a doctrine of responsibility of care--a sense of "ad meliora vertamur" (let us turn to better things). It provides a brief history of "in loco parentis" as it has developed in the U.S. as well as the difficulties it faces in modern academe.…

  4. Regulation of longevity by regulator of G-protein signaling protein, Loco.

    Science.gov (United States)

    Lin, Yuh-Ru; Kim, Keetae; Yang, Yanfei; Ivessa, Andreas; Sadoshima, Junichi; Park, Yongkyu

    2011-06-01

    Regulator of G-protein signaling (RGS) proteins contribute to G-protein signaling pathways as activators or repressors with GTPase-activating protein (GAP) activity. To characterize whether regulation of RGS proteins influences longevity in several species, we measured stress responses and lifespan of RGS-overexpressing and RGS-lacking mutants. Reduced expression of Loco, a RGS protein of Drosophila melanogaster, resulted in a longer lifespan for both male and female flies, also exhibiting stronger resistance to three different stressors (starvation, oxidation, and heat) and higher manganese-containing superoxide dismutase (MnSOD) activity. In addition, this reduction in Loco expression increased fat content and diminished cAMP levels. In contrast, overexpression of both genomic and cDNA loco gene significantly shortened the lifespan with weaker stress resistance and lower fat content. Deletion analysis of the Loco demonstrated that its RGS domain is required for the regulation of longevity. Consistently, when expression of RGS14, mammalian homologue of Loco, was reduced in rat fibroblast cells, the resistance to oxidative stress increased with higher MnSOD expression. The changes of yeast Rgs2 expression, which shares a conserved RGS domain with the fly Loco protein, also altered lifespan and stress resistance in Saccharomyces cerevisiae. Here, we provide the first evidence that RGS proteins with GAP activity affect both stress resistance and longevity in several species.

  5. Predictors of loco-regional recurrence and cancer-related death after breast cancer surgery.

    Science.gov (United States)

    Rausei, Stefano; Rovera, Francesca; Dionigi, Gianlorenzo; Tornese, Deborah; Fachinetti, Anna; Boni, Luigi; Dionigi, Renzo

    2010-01-01

    To determine which tumor-related factors might predispose the patient to loco-regional recurrence or death and the impact of these factors on the different types of events. We retrospectively analyzed the data of 1991 women between January 1998 and March 2010 for a first primary nonmetastatic breast cancer and treated with surgery and neo-adjuvant/adjuvant therapy. The overall survival distribution was estimated using the Kaplan-Meier method. The prognostic impact of several factors on cumulative overall and loco-regional recurrence free survival was evaluated by univariate (log-rank test) and multivariate analysis (Cox regression). At log-rank test, pT, nodal status, histotype, grading, lymphangioinvasive growth, tumor diameter, estrogen receptors (ER) status, progesterone receptors (PR) status, expression of Ki67, and expression of Her2/neu had a prognostic value on loco-regional recurrence or overall survival. In the multivariate analysis grading remained the only independent predictor of loco-regional recurrences. With regard to overall survival, the Cox model selected grading along with nodal status and PR status. Loco-regional recurrences after breast cancer surgery are not frequent events. They are markers of tumor aggressiveness and predictor of an increased likelihood of cancer-related death. However, loco-regional recurrence and systemic tumor progression are partially independent events, since some prognostic factors differ.

  6. Numerical simulation on bearing force of propeller for machining errors in non-uniform inflow

    Directory of Open Access Journals (Sweden)

    YU Anbin

    2017-03-01

    Full Text Available In order to study the bearing force caused by the machining errors of composite material propeller in non-uniform flow, the propeller was computed by changing the machining error of the propeller in six degrees of freedom, in which the main blade translates and rotates along the coordinate axis artificially by way of the statistical method. The bearing force of a DTMB P4119 propeller with a machining error was calculated according to the SST k-ω model and sliding meshing non-uniform flow to figure out the impact of various machining errors on the propeller, enabling a fundamental rule about the impact of various machining errors on a propeller's bearing force to be formed. The results show that vertical bearing force and horizontal bearing force increase linearly, and first-order blade frequency bearing force rarely changes with the increase of machining errors in each freedom; machining errors along the directions of diameter and pitch have a great impact on the propeller shaft's frequency bearing force. Therefore, we can put forward a more refined principle about the machining accuracy of propellers.

  7. Implementing Scientific Simulation Codes Highly Tailored for Vector Architectures Using Custom Configurable Computing Machines

    Science.gov (United States)

    Rutishauser, David

    2006-01-01

    The motivation for this work comes from an observation that amidst the push for Massively Parallel (MP) solutions to high-end computing problems such as numerical physical simulations, large amounts of legacy code exist that are highly optimized for vector supercomputers. Because re-hosting legacy code often requires a complete re-write of the original code, which can be a very long and expensive effort, this work examines the potential to exploit reconfigurable computing machines in place of a vector supercomputer to implement an essentially unmodified legacy source code. Custom and reconfigurable computing resources could be used to emulate an original application's target platform to the extent required to achieve high performance. To arrive at an architecture that delivers the desired performance subject to limited resources involves solving a multi-variable optimization problem with constraints. Prior research in the area of reconfigurable computing has demonstrated that designing an optimum hardware implementation of a given application under hardware resource constraints is an NP-complete problem. The premise of the approach is that the general issue of applying reconfigurable computing resources to the implementation of an application, maximizing the performance of the computation subject to physical resource constraints, can be made a tractable problem by assuming a computational paradigm, such as vector processing. This research contributes a formulation of the problem and a methodology to design a reconfigurable vector processing implementation of a given application that satisfies a performance metric. A generic, parametric, architectural framework for vector processing implemented in reconfigurable logic is developed as a target for a scheduling/mapping algorithm that maps an input computation to a given instance of the architecture. This algorithm is integrated with an optimization framework to arrive at a specification of the architecture parameters

  8. Simulation and Prediction of Alkalinity in Sintering Process Based on Grey Least Squares Support Vector Machine

    Institute of Scientific and Technical Information of China (English)

    SONG Qiang; WANG Ai-min

    2009-01-01

    The prediction of the alkalinity is difficult during the sintering process. Whether or not the level of the alkalinity of sintering process is successful is directly related to the quality of sinter. There is no very good method for predicting the alkalinity by now owing to the high complexity, high nonlinearity, strong coupling, high time delay, and etc. Therefore, a new technique, the grey squares support machine, was introduced. The grey support vector machine model of the alkalinity enabled the development of new equation and algorithm to predict the alkalinity. During modelling, the fluctuation of data sequence was weakened by the grey theory and the support vector machine was capable of processing nonlinear adaptable information, and the grey support vector machine has a combination of those advantages. The results revealed that the alkalinity of sinter could be accurately predicted using this model by reference to small sample and information. The experimental results showed that the grey support vector machine model was effective and practical owing to the advantages of high precision, less samples required, and simple calculation.

  9. [Loco-regional chemotherapy at the outpatient clinic for gastric cancer patients with home enteral nutrition].

    Science.gov (United States)

    Maruyama, Michio; Nagahama, Takeshi; Sugano, Norihide; Satoh, Eigo; Maruyama, Shouji; Tanami, Hideo; Chiba, Tetsuma; Murakata, Ayano; Mitsuhashi, Yosuke; Uehira, Daisuke; Akazawa, Naoya; Suzuki, Keiichirou

    2011-11-01

    In over the 10 years from 2000-2010, 21 gastric cancer patients received loco-regional chemotherapy with home enteral nutrition (HEN) at an outpatient clinic because of insufficient oral intake. These loco-regional chemotherapy regimens consisted of 5 intra-aortic chemotherapies, 4 hepato-arterial infusions and 12 intra-peritoneal chemotherapies. Five out of 8 cases that had measurable lesions showed PR, and 3 cases revealed PD. The patients received HEN with peptide central formula, 400-1,200 kcal/day in night time. The average duration of HEN was 12.9 months. The post-operative nutritional management was needed for continuation and securing of outpatient chemotherapy. The author reported an experience of the outpatient loco-regional chemotherapy with HEN for the gastric cancer patients who could not eat a sufficient volume of food.

  10. CAMELOT: A machine learning approach for coarse-grained simulations of aggregation of block-copolymeric protein sequences

    Energy Technology Data Exchange (ETDEWEB)

    Ruff, Kiersten M. [Computational and Systems Biology Program and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130-4899 (United States); Harmon, Tyler S. [Department of Physics and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130-4899 (United States); Pappu, Rohit V., E-mail: pappu@wustl.edu [Department of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, CB 1097, St. Louis, Missouri 63130-4899 (United States)

    2015-12-28

    We report the development and deployment of a coarse-graining method that is well suited for computer simulations of aggregation and phase separation of protein sequences with block-copolymeric architectures. Our algorithm, named CAMELOT for Coarse-grained simulations Aided by MachinE Learning Optimization and Training, leverages information from converged all atom simulations that is used to determine a suitable resolution and parameterize the coarse-grained model. To parameterize a system-specific coarse-grained model, we use a combination of Boltzmann inversion, non-linear regression, and a Gaussian process Bayesian optimization approach. The accuracy of the coarse-grained model is demonstrated through direct comparisons to results from all atom simulations. We demonstrate the utility of our coarse-graining approach using the block-copolymeric sequence from the exon 1 encoded sequence of the huntingtin protein. This sequence comprises of 17 residues from the N-terminal end of huntingtin (N17) followed by a polyglutamine (polyQ) tract. Simulations based on the CAMELOT approach are used to show that the adsorption and unfolding of the wild type N17 and its sequence variants on the surface of polyQ tracts engender a patchy colloid like architecture that promotes the formation of linear aggregates. These results provide a plausible explanation for experimental observations, which show that N17 accelerates the formation of linear aggregates in block-copolymeric N17-polyQ sequences. The CAMELOT approach is versatile and is generalizable for simulating the aggregation and phase behavior of a range of block-copolymeric protein sequences.

  11. Computational Fluid Dynamic Simulation of Flow in Abrasive Water Jet Machining

    Science.gov (United States)

    Venugopal, S.; Sathish, S.; Jothi Prakash, V. M.; Gopalakrishnan, T.

    2017-03-01

    Abrasive water jet cutting is one of the most recently developed non-traditional manufacturing technologies. In this machining, the abrasives are mixed with suspended liquid to form semi liquid mixture. The general nature of flow through the machining, results in fleeting wear of the nozzle which decrease the cutting performance. The inlet pressure of the abrasive water suspension has main effect on the major destruction characteristics of the inner surface of the nozzle. The aim of the project is to analyze the effect of inlet pressure on wall shear and exit kinetic energy. The analysis could be carried out by changing the taper angle of the nozzle, so as to obtain optimized process parameters for minimum nozzle wear. The two phase flow analysis would be carried by using computational fluid dynamics tool CFX. It is also used to analyze the flow characteristics of abrasive water jet machining on the inner surface of the nozzle. The availability of optimized process parameters of abrasive water jet machining (AWJM) is limited to water and experimental test can be cost prohibitive. In this case, Computational fluid dynamics analysis would provide better results.

  12. Machine vision-based high-resolution weed mapping and patch-sprayer performance simulation

    NARCIS (Netherlands)

    Tang, L.; Tian, L.F.; Steward, B.L.

    1999-01-01

    An experimental machine vision-based patch-sprayer was developed. This sprayer was primarily designed to do real-time weed density estimation and variable herbicide application rate control. However, the sprayer also had the capability to do high-resolution weed mapping if proper mapping techniques

  13. A Gradient-Simulated Annealing Algorithm of Pre-location-Based Best Fitting of Blank to Complex Surfaces Machining

    Institute of Scientific and Technical Information of China (English)

    MALi-ming; JIANGHong; WANGXiao-chun

    2004-01-01

    The algorithm is divided into two steps. The first step pre-locates the blank by aligning its centre of gravity and approximate normal vector with those of destination surfaces, with largest overlap of projections of two objects on a plane perpendicular to the normal vector. The second step is optimizing an objective function by means of gradient-simulated annealing algorithm to get the best matching of a set of distributed points on the blank and destination surfaces. An example for machining hydroelectric turbine blades is given to verify the effectiveness of algorithm.

  14. Magnetic resonance imaging of the liver after loco-regional and systemic therapy.

    Science.gov (United States)

    Corona-Villalobos, Celia Pamela; Zhang, Yan; Zhang, Wei-Dong; Kamel, Ihab R

    2014-08-01

    Assessment of tumor response is crucial in determining the effectiveness of loco-regional and systemic therapy, and for determining the need for subsequent treatment. The ultimate goal is to improve patient's survival. Changes in tumor size and enhancement after therapy may not be detected early by the traditional response criteria. Tumor response is better assessed in the entire tumor volume rather than in a single axial plane. The purpose of this article is to familiarize the reader with early treatment response assessed by anatomic and volumetric functional magnetic resonance imaging metrics of the liver after loco-regional and systemic therapy.

  15. Action Identity in Style Simulation Systems: Do Players Consider Machine-Generated Music As of Their Own Style?

    Science.gov (United States)

    Khatchatourov, Armen; Pachet, François; Rowe, Victoria

    2016-01-01

    The generation of musical material in a given style has been the subject of many studies with the increased sophistication of artificial intelligence models of musical style. In this paper we address a question of primary importance for artificial intelligence and music psychology: can such systems generate music that users indeed consider as corresponding to their own style? We address this question through an experiment involving both performance and recognition tasks with musically naïve school-age children. We asked 56 children to perform a free-form improvisation from which two kinds of music excerpt were created. One was a mere recording of original performances. The other was created by a software program designed to simulate the participants' style, based on their original performances. Two hours after the performance task, the children completed the recognition task in two conditions, one with the original excerpts and one with machine-generated music. Results indicate that the success rate is practically equivalent in two conditions: children tended to make correct attribution of the excerpts to themselves or to others, whether the music was human-produced or machine-generated (mean accuracy = 0.75 and = 0.71, respectively). We discuss this equivalence in accuracy for machine-generated and human produced music in the light of the literature on memory effects and action identity which addresses the recognition of one's own production.

  16. Inferring planar disorder in close-packed structures via ε-machine spectral reconstruction theory: examples from simulated diffraction patterns.

    Science.gov (United States)

    Varn, D P; Canright, G S; Crutchfield, J P

    2013-07-01

    A previous paper detailed a novel algorithm, ε-machine spectral reconstruction theory (εMSR), that infers pattern and disorder in planar-faulted, close-packed structures directly from X-ray diffraction patterns [Varn et al. (2013). Acta Cryst. A69, 197-206]. Here εMSR is applied to simulated diffraction patterns from four close-packed crystals. It is found that, for stacking structures with a memory length of three or less, εMSR reproduces the statistics of the stacking structure; the result being in the form of a directed graph called an ε-machine. For stacking structures with a memory length larger than three, εMSR returns a model that captures many important features of the original stacking structure. These include multiple stacking faults and multiple crystal structures. Further, it is found that εMSR is able to discover stacking structure in even highly disordered crystals. In order to address issues concerning the long-range order observed in many classes of layered materials, several length parameters are defined, calculable from the ε-machine, and their relevance is discussed.

  17. End mill tools integration in CNC machining for rapid manufacturing processes: simulation studies

    OpenAIRE

    Muhammed Nafis Osman Zahid; Keith Case; Darren Watts

    2015-01-01

    Computer numerical controlled (CNC) machining has been recognized as a manufacturing process that is capable of producing metal parts with high precision and reliable quality, whereas many additive manufacturing methods are less capable in these respects. The introduction of a new layer-removal methodology that utilizes an indexing device to clamp the workpiece can be used to extend CNC applications into the realm of rapid manufacturing (CNC-RM) processes. This study aims to improve the imple...

  18. End mill tools integration in CNC machining for rapid manufacturing processes: simulation studies

    OpenAIRE

    Muhammed Nafis Osman Zahid; Keith Case; Darren Watts

    2015-01-01

    Computer numerical controlled (CNC) machining has been recognized as a manufacturing process that is capable of producing metal parts with high precision and reliable quality, whereas many additive manufacturing methods are less capable in these respects. The introduction of a new layer-removal methodology that utilizes an indexing device to clamp the workpiece can be used to extend CNC applications into the realm of rapid manufacturing (CNC-RM) processes. This study aims to improve the imple...

  19. A Novel Cogging Torque Simulation Method for Permanent-Magnet Synchronous Machines

    OpenAIRE

    Chun-Yu Hsiao; Jonq-Chin Hwang; Sheng-Nian Yeh

    2011-01-01

    Cogging torque exists between rotor mounted permanent magnets and stator teeth due to magnetic attraction and this is an undesired phenomenon which produces output ripple, vibration and noise in machines. The purpose of this paper is to study the existence and effects of cogging torque, and to present a novel, rapid, half magnet pole pair technique for forecasting and evaluating cogging torque. The technique uses the finite element method as well as Matlab research and development oriented so...

  20. Technico-economic simulation and optimization of a compression refrigerating machine

    Energy Technology Data Exchange (ETDEWEB)

    Grosu, Lavinia; Benelmir, Riad; Feidt, Michel [CNRS, LEMTA, Vandoeuvre-Les-Nancy, 54 (France)

    1999-11-01

    This study is among the several works conducted by the authors with regard to technico-economic optimisation of refrigerating machines. The most difficult part is the gathering of technico-economical data and the development of cost correlations. The tool presented in this work will be used for an optimisation based on irreversibilities and cost minimisation, since irreversibilities have a direct impact on the operating cost. (Author)

  1. A comparison of machine learning algorithms for chemical toxicity classification using a simulated multi-scale data model

    Directory of Open Access Journals (Sweden)

    Li Zhen

    2008-05-01

    Full Text Available Abstract Background Bioactivity profiling using high-throughput in vitro assays can reduce the cost and time required for toxicological screening of environmental chemicals and can also reduce the need for animal testing. Several public efforts are aimed at discovering patterns or classifiers in high-dimensional bioactivity space that predict tissue, organ or whole animal toxicological endpoints. Supervised machine learning is a powerful approach to discover combinatorial relationships in complex in vitro/in vivo datasets. We present a novel model to simulate complex chemical-toxicology data sets and use this model to evaluate the relative performance of different machine learning (ML methods. Results The classification performance of Artificial Neural Networks (ANN, K-Nearest Neighbors (KNN, Linear Discriminant Analysis (LDA, Naïve Bayes (NB, Recursive Partitioning and Regression Trees (RPART, and Support Vector Machines (SVM in the presence and absence of filter-based feature selection was analyzed using K-way cross-validation testing and independent validation on simulated in vitro assay data sets with varying levels of model complexity, number of irrelevant features and measurement noise. While the prediction accuracy of all ML methods decreased as non-causal (irrelevant features were added, some ML methods performed better than others. In the limit of using a large number of features, ANN and SVM were always in the top performing set of methods while RPART and KNN (k = 5 were always in the poorest performing set. The addition of measurement noise and irrelevant features decreased the classification accuracy of all ML methods, with LDA suffering the greatest performance degradation. LDA performance is especially sensitive to the use of feature selection. Filter-based feature selection generally improved performance, most strikingly for LDA. Conclusion We have developed a novel simulation model to evaluate machine learning methods for the

  2. 基于UG的喷注器冷却通道的机床仿真加工%UG-based machining simulation of injector cooling channel

    Institute of Scientific and Technical Information of China (English)

    刘英; 董文英

    2011-01-01

    在分析了喷注器壳体上冷却通道的结构特点和数控加工工艺的基础上,利用UG/ISV软件进行冷却通道的辅助加工,同时对喷注器三维模型的建立、加工过程参数的选用及刀具轨迹编程和加工仿真进行了详细介绍,并用五轴机床进行了加工实验,保证了加工质量,提高了加工效率。%Based on the analyses of structural features of cooling channel on the injector shell and NC machining process, computer-aided machining of cooling channel was conducted with UG/ISV software. The 3D injector model, machining parameter selection, tool path programming and machining simulation are introduced in detail. A 5-axis machine was adopted to carry out machining tests. The result proves that the above process can ensure the machining quality and improve the machining efficiency.

  3. Pedagogical "In Loco Parentis": Reflecting on Power and Parental Authority in the Writing Classroom

    Science.gov (United States)

    Podis, JoAnne; Podis, Leonard

    2007-01-01

    In higher education, issues of "in loco parentis" have been most often discussed in connection with campus administrative policies. College writing teachers need to reflect, however, on the ways they conceivably exercise parental authority in their own classrooms, through such models as the Stern Father and the Nurturing Mother. (Contains 26…

  4. [Role of loco-regional treatments for patients with breast cancer liver metastases].

    Science.gov (United States)

    Raimondi, Cristina; Danova, Marco; Chatzileontiadou, Sofia; Palmeri, Laura; Vercelli, Alessandro; Palmeri, Sergio

    2009-09-01

    Breast cancer liver metastases (BCLM) are not uncommon (about 18% of cases): although some patients have been reported as still living after 25 months, median survival after hormonal- or chemotherapy is 6-14 months. In recent years, new chemotherapy regimens and molecular targeted therapies have given medical oncologists reason to believe that metastatic disease can be eradicated, or at least controlled for prolonged periods. In an attempt to improve survival, consideration has also been given to loco-regional treatments such as hepatic resection and radio-frequency ablation, which have been associated with better outcomes in selected patients. This review considers the role of two loco-regional approaches in a multidisciplinary perspective in the treatment of single or multiple breast cancer metastases limited to the liver. An expanded role for hepatic resection and ablation is being investigated. We assessed available data in the literature to determine their role on survival outcomes. They suggest that loco-regional treatments might be of significant benefit in a selected group of women with BCLM, but the role of these local treatments in multimodality treatment of liver metastases remains controversial. It can generally be said that loco-regional treatments can improve overall survival, with no mortality and less than 20% morbidity in patients at low surgical risk; however, they should only be considered cytoreductive treatments and, as such, always need to be integrated with systemic therapy.

  5. In Loco Parentis and the New Age of Majority: The Views of Freshmen and Their Parents

    Science.gov (United States)

    Devine, Howard F.; Loesch, Larry C.

    1976-01-01

    Research has shown parents have strongly favored in loco parentis and students have not. This study found that, despite the increasing recognition of 18 as legal adulthood, there are still differences between attitudes of students and parents regarding the university's parental role, although both groups favored some university control. (Author)

  6. In Loco Parentis: Alive and Kicking, Dead and Buried, or Rising Phoenix? ASHE Annual Meeting Paper.

    Science.gov (United States)

    Edwards, Alan F., Jr.

    This paper reviews the conflicting literature on "in loco parentis" as applied to college settings. Specifically, attention is focused on three areas: (1) the roots, origins, and early history of the concept; (2) the concept's apparent demise in the 1960s; and (3) its recent comeback as a hot topic. The doctrine of "in loco…

  7. Pedagogical "In Loco Parentis": Reflecting on Power and Parental Authority in the Writing Classroom

    Science.gov (United States)

    Podis, JoAnne; Podis, Leonard

    2007-01-01

    In higher education, issues of "in loco parentis" have been most often discussed in connection with campus administrative policies. College writing teachers need to reflect, however, on the ways they conceivably exercise parental authority in their own classrooms, through such models as the Stern Father and the Nurturing Mother. (Contains 26…

  8. The Lunar Occultation Observer (LOCO) - A Nuclear Astrophysics All-Sky Survey Mission Concept

    Science.gov (United States)

    Miller, R. S.; Bonamente, M.; Burgess, J. M.; Harmon, B. A.; Jenke, P.; Lawrence, D. J.; O'Brien, S.; Orr, M. R.; Paciesas, W. S.; Young, C. A.

    2008-07-01

    The Lunar Occultation Observer (LOCO) is a new lunar-based concept to probe the nuclear astrophysics regime. It will be a pioneering mission in high-energy astrophysics: the first to employ occultation as the principle detection and imaging method.

  9. "In Loco Emporium": Immigrant Youth and Educators in the Social Contracts of Education

    Science.gov (United States)

    Patel, Lisa

    2013-01-01

    For adults training to be professional educators, the phrase, "in loco parentis," communicates the intention that schools and educators are meant to act in the role of the parent, commonly interpreted to mean acting in accordance with what is optimal for the development of the child or young person. The limits of this relationship have…

  10. Delictual Negligence of Educators in Schools: The Confusing Influence of the "in loco parentis" Doctrine

    Science.gov (United States)

    Potgieter, Johan

    2004-01-01

    This article points out that the "in loco parentis" maxim is partly to blame for introducing the confusing "reasonable parent" doctrine as the test for delictual negligence of educators in the school context. It is argued that the standard of care exercised by parents over their children is not appropriate to determine the negligence of educators.…

  11. In Loco Parentis Reinventis: Is There Still a Parenting Function in Higher Education?

    Science.gov (United States)

    Gregory, Dennis E.; Ballou, Roger A.

    1986-01-01

    Traces the history of the term in loco parentis, its decreased utility in the 1960s, and its recent evolution in different and more subtle ways. Supports the view that colleges are still very involved in acting as surrogate parents for their students. (Author/ABB)

  12. Model design and simulation of automatic sorting machine using proximity sensor

    Directory of Open Access Journals (Sweden)

    Bankole I. Oladapo

    2016-09-01

    Full Text Available The automatic sorting system has been reported to be complex and a global problem. This is because of the inability of sorting machines to incorporate flexibility in their design concept. This research therefore designed and developed an automated sorting object of a conveyor belt. The developed automated sorting machine is able to incorporate flexibility and separate species of non-ferrous metal objects and at the same time move objects automatically to the basket as defined by the regulation of the Programmable Logic Controllers (PLC with a capacitive proximity sensor to detect a value range of objects. The result obtained shows that plastic, wood, and steel were sorted into their respective and correct position with an average, sorting, time of 9.903 s, 14.072 s and 18.648 s respectively. The proposed developed model of this research could be adopted at any institution or industries, whose practices are based on mechatronics engineering systems. This is to guide the industrial sector in sorting of object and teaching aid to institutions and hence produce the list of classified materials according to the enabled sorting program commands.

  13. Loco-regional treatment in metastatic breast cancer patients: is there a survival benefit?

    Science.gov (United States)

    Ly, Bevan H; Nguyen, Nam P; Vinh-Hung, Vincent; Rapiti, Elisabetta; Vlastos, Georges

    2010-02-01

    A number of studies have recently demonstrated a survival benefit in stage IV breast cancer patients following surgical resection of the primary tumor. Here, we investigate the relationship between loco-regional treatment and survival in patients with metastatic breast cancer and evaluate the impact of different loco-regional treatments. We conducted a systematic review of the literature using PubMed to analyze studies with the following criteria: Type of loco-regional treatment (surgery alone or combined with radiation, radiotherapy), overall survival, progression-free survival, selection factors for local treatment, and complication rates. Thirteen studies evaluated the effect of loco-regional treatment on overall survival with overall median survival increasing from a range of 12.6-28.3 months among patients without surgery to a range of 25-42 months among patients with surgery. In addition, six studies reported a 3-year survival benefit of 28-95% and 17-79% in women with and without locoregional therapy respectively. Two studies did not find any improvement in overall survival. One study found an improvement in 5-year breast cancer-specific survival of 27% with negative surgical margins versus 12% with no surgery. Three studies reported an advantage in progression-free survival in the treatment group compared with the non-treatment group. Loco-regional treatment for breast cancer patients with distant metastases at diagnosis is an important issue because of possible improvement of survival or disease-free survival. The possibility of surgery and/or radiotherapy following induction chemotherapy should be weighed and left to individual practice. Participation in randomized controlled trials should be encouraged.

  14. A Universal Reactive Machine

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif; Mørk, Simon; Sørensen, Morten U.

    1997-01-01

    Turing showed the existence of a model universal for the set of Turing machines in the sense that given an encoding of any Turing machine asinput the universal Turing machine simulates it. We introduce the concept of universality for reactive systems and construct a CCS processuniversal...

  15. TO A QUESTION ON ADVANTAGES AND SHORTCOMINGS OF VARIOUS TYPES OF EXCHANGE SIMULATORS-EXERCISE MACHINES

    Directory of Open Access Journals (Sweden)

    T. V. Nikitina

    2016-01-01

    Full Text Available According to Walter Ron, business games are a tool of the future in the area of graduate education. They are very realistically simulating the professional activities of the administrative staff . In this connection, this article focuses on the use and improvement of the business, in particular, exchange, games.The purpose of research - analysis of the advantages and disadvantages of diff erent types of exchange simulatorssimulators. This goal has led to the need to solve the following tasks: to consider a variety of computer games and simulators exchange; assess their strengths and weaknesses; be compared on diff erent criteria used in the practice of stock simulators ("Game", "Network", "Broker" ("Teaching with ET" using virtual money, "Simulation". The study is based on the method of comparative analysis in relation to the actual species of exchange stimulants, as well as compared to the exchange simulators with other active learning methods. The result of the study was to identify the most eff ective simulation applied to the most common problems facing them. Upon review of the article provides recommendations on improving the "exchange game", their functionality and architecture used in the training of investors – individuals. Particular attention is paid to the need to improve the educational industrial complex (CPC "Stock Market Game", which authors use in educational activities when working with students. The paper formulated the conclusion that one of the main functional advantages is the ability to exchange simulators mining investment activities, testing of investment strategies in crisis situations without the risk of losing real funds. The economic basis for the use of stock simulators in training is the fact that they are significantly save the real capital, especially in the case of investment or operating errors trainees. In this connection, the use of stock simulators for teaching exchange business is a must, as their use

  16. Estimating Fractional Shrub Cover Using Simulated EnMAP Data: A Comparison of Three Machine Learning Regression Techniques

    Directory of Open Access Journals (Sweden)

    Marcel Schwieder

    2014-04-01

    Full Text Available Anthropogenic interventions in natural and semi-natural ecosystems often lead to substantial changes in their functioning and may ultimately threaten ecosystem service provision. It is, therefore, necessary to monitor these changes in order to understand their impacts and to support management decisions that help ensuring sustainability. Remote sensing has proven to be a valuable tool for these purposes, and especially hyperspectral sensors are expected to provide valuable data for quantitative characterization of land change processes. In this study, simulated EnMAP data were used for mapping shrub cover fractions along a gradient of shrub encroachment, in a study region in southern Portugal. We compared three machine learning regression techniques: Support Vector Regression (SVR; Random Forest Regression (RF; and Partial Least Squares Regression (PLSR. Additionally, we compared the influence of training sample size on the prediction performance. All techniques showed reasonably good results when trained with large samples, while SVR always outperformed the other algorithms. The best model was applied to produce a fractional shrub cover map for the whole study area. The predicted patterns revealed a gradient of shrub cover between regions affected by special agricultural management schemes for nature protection and areas without land use incentives. Our results highlight the value of EnMAP data in combination with machine learning regression techniques for monitoring gradual land change processes.

  17. The Research on Volleyball Trajectory Simulation Based on Cost-Sensitive Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Yan Binghong

    2013-07-01

    Full Text Available Aim of study of the study is to effectively solve the imbalanced data sets classification problem, the field of machine learning proposed many effective algorithms. On Seabrook’s view, now the classification methods for class imbalance problem can be broadly divided into two categories, one class is to create new methods or improve the existing methods based on the characteristics of class imbalance. Another is to reduce class imbalance effect re-use of existing methods by resembling technique. But there are also some drawbacks in resembling method. Sample set sampling may lead to excessive learning; the next sample may result in the training set. Therefore, by dividing the training set, it does not increase the number of training samples; also it is without loss of useful information in the sample to obtain a certain degree of balance in a subset of the problem.

  18. 3-D Numerical Simulation on the Chip Machining Process of a Metal Block

    Institute of Scientific and Technical Information of China (English)

    Yan Yixia; Yin Yihui; Li Weifen

    2004-01-01

    In this paper, the cutting process of a metal block is numerically simulated by the dynamic explicit FE code ABAQUS. Taking thermo-mechanical coupling effect into consideration, the simulation presents the variation of temperature, stress and strain distribution in the workpiece and chip. The effective plastic strain failure criterion is applied to modeling the chip separation and plastic formation. And the phenomenon of the contact and friction between the workpiece and the cutting tool are described in the paper.

  19. A Single-Machine Two-Agent Scheduling Problem by a Branch-and-Bound and Three Simulated Annealing Algorithms

    Directory of Open Access Journals (Sweden)

    Shangchia Liu

    2015-01-01

    Full Text Available In the field of distributed decision making, different agents share a common processing resource, and each agent wants to minimize a cost function depending on its jobs only. These issues arise in different application contexts, including real-time systems, integrated service networks, industrial districts, and telecommunication systems. Motivated by its importance on practical applications, we consider two-agent scheduling on a single machine where the objective is to minimize the total completion time of the jobs of the first agent with the restriction that an upper bound is allowed the total completion time of the jobs for the second agent. For solving the proposed problem, a branch-and-bound and three simulated annealing algorithms are developed for the optimal solution, respectively. In addition, the extensive computational experiments are also conducted to test the performance of the algorithms.

  20. Thyroid Cells Exposed to Simulated Microgravity Conditions - Comparison of the Fast Rotating Clinostat and the Random Positioning Machine

    Science.gov (United States)

    Warnke, Elisabeth; Kopp, Sascha; Wehland, Markus; Hemmersbach, Ruth; Bauer, Johann; Pietsch, Jessica; Infanger, Manfred; Grimm, Daniela

    2016-06-01

    The ground-based facilities 2D clinostat (CN) and Random Positioning Machine (RPM) were designed to simulate microgravity conditions on Earth. With support of the CORA-ESA-GBF program we could use both facilities to investigate the impact of simulated microgravity on normal and malignant thyroid cells. In this review we report about the current knowledge of thyroid cancer cells and normal thyrocytes grown under altered gravity conditions with a special focus on growth behaviour, changes in the gene expression pattern and protein content, as well as on altered secretion behaviour of the cells. We reviewed data obtained from normal thyrocytes and cell lines (two poorly differentiated follicular thyroid cancer cell lines FTC-133 and ML-1, as well as the normal thyroid cell lines Nthy-ori 3-1 and HTU-5). Thyroid cells cultured under conditions of simulated microgravity (RPM and CN) and in Space showed similar changes with respect to spheroid formation. In static 1 g control cultures no spheroids were detectable. Changes in the regulation of cytokines are discussed to be involved in MCS (multicellular spheroids) formation. The ESA-GBF program helps the scientists to prepare future spaceflight experiments and furthermore, it might help to identify targets for drug therapy against thyroid cancer.

  1. POSTCOLONIALIDAD Y DESCOLONIALIDAD EN LOCO AFÁN: CRÓNICAS DE SIDARIO DE PEDRO LEMEBEL Postcolonialism and Decolonialism in Pedro Lemebel’s Loco Afán: Crónicas de Sidario

    Directory of Open Access Journals (Sweden)

    Jorge Lagos Caamaño

    2011-12-01

    Full Text Available Este trabajo tiene como propósito fundamental evidenciar la presencia de algunos rasgos del pensamiento postcolonial y descolonial en Loco afán. Crónicas de sidario de Pedro Lemebel.The fundamental purpose of the present work is to evidence the presence of some features of postcolonial and decolonial thought in Pedro Lemebel’s Loco Afán. Crónicas de Sidario.

  2. Simulation guided value stream mapping and lean improvement: A case study of a tubular machining facility

    Directory of Open Access Journals (Sweden)

    Wei Xia

    2013-06-01

    Full Text Available Purpose: This paper describes a typical Value stream mapping (VSM application enhanced by the discrete event simulation (DES to a dedicated tubular manufacturing process. Design/Methodology/Approach: VSM is prescribed as part of lean production portfolio of tools, not only highlights process inefficiencies, transactional and communication mismatches, but also guides improvement areas. Meanwhile, DES is used to reduce uncertainty and create consensus by visualizing dynamic process views. It is served as a complementary tool for the traditional VSM to provide sufficient justification and quantifiable evidence needed to convince the lean approaches. A simulation model is developed to replicate the operation of an existing system, and that of a proposed system that modifies the existing design to incorporate lean manufacturing shop floor principles. Findings: A comprehensive model for the tubular manufacturing process is constructed, and distinctive scenarios are derived to uncover an optimal future state of the process. Various simulation scenarios are developed. The simulated results are acquired and investigated, and they are well matched with the real production data. Originality/Value: DES is demonstrated as a guided tool to assist organizations with the decision to implement lean approaches by quantifying benefits from applying the VSM. A roadmap is provided to illustrate how the VSM is used to design a desired future state. The developed simulation scenarios mimic the behavior of the actual manufacturing process in an intuitive manner.

  3. A study on fluid flow simulation in the cooling systems of machine tools

    Science.gov (United States)

    Olaru, I.

    2016-08-01

    This paper aims analysing the type of coolants and the correct choice of that as well as the dispensation in the processing area to control the temperature resulted from the cutting operation and the choose of the cutting operating modes. A high temperature in the working area over a certain amount can be harmful in terms of the quality of resulting surface and that could have some influences on the life of the cutting tool. The coolant chosen can be a combination of different cooling fluids in order to achieve a better cooling of the cutting area at the same time for carrying out the proper lubrication of that area. The fluid flow parameters of coolant can be influenced by the nature of the fluid or fluids used, the geometry of the nozzle used which generally has a convergent-divergent geometry in order to achieve a better dispersion of the coolant / lubricant on the area to be processed. A smaller amount of fluid is important in terms of the economy lubricant, because they are quite expensive. A minimal amount of lubricant may have a better impact on the environment and the health of the operator because the coolants in contact with overheated machined surface may develop a substantial amount of these gases that are not always beneficial to health.

  4. Man, mind, and machine: the past and future of virtual reality simulation in neurologic surgery.

    Science.gov (United States)

    Robison, R Aaron; Liu, Charles Y; Apuzzo, Michael L J

    2011-11-01

    To review virtual reality in neurosurgery, including the history of simulation and virtual reality and some of the current implementations; to examine some of the technical challenges involved; and to propose a potential paradigm for the development of virtual reality in neurosurgery going forward. A search was made on PubMed using key words surgical simulation, virtual reality, haptics, collision detection, and volumetric modeling to assess the current status of virtual reality in neurosurgery. Based on previous results, investigators extrapolated the possible integration of existing efforts and potential future directions. Simulation has a rich history in surgical training, and there are numerous currently existing applications and systems that involve virtual reality. All existing applications are limited to specific task-oriented functions and typically sacrifice visual realism for real-time interactivity or vice versa, owing to numerous technical challenges in rendering a virtual space in real time, including graphic and tissue modeling, collision detection, and direction of the haptic interface. With ongoing technical advancements in computer hardware and graphic and physical rendering, incremental or modular development of a fully immersive, multipurpose virtual reality neurosurgical simulator is feasible. The use of virtual reality in neurosurgery is predicted to change the nature of neurosurgical education, and to play an increased role in surgical rehearsal and the continuing education and credentialing of surgical practitioners. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Combining human and machine expertise for self-directed learning in simulation-based discovery environments

    NARCIS (Netherlands)

    de Jong, Anthonius J.M.; van Joolingen, Wouter; Swaak, Janine; Veermans, K.H.; Limbach, R.; King, S.; Gureghian, D.

    1998-01-01

    SIMQUEST is an authoring system for designing and creating simulation-based learning environments. The special character of SIMQUEST learning environments is that they include cognitive support for learners which means that they provide learners with support in the discovery process. In SIMQUEST

  6. Combining human and machine expertise for self-directed learning in simulation-based discovery environments

    NARCIS (Netherlands)

    de Jong, Anthonius J.M.; van Joolingen, Wouter; Swaak, Janine; Veermans, K.H.; Limbach, R.; King, S.; Gureghian, D.

    1998-01-01

    SIMQUEST is an authoring system for designing and creating simulation-based learning environments. The special character of SIMQUEST learning environments is that they include cognitive support for learners which means that they provide learners with support in the discovery process. In SIMQUEST lea

  7. Pattern of loco-regional failure after definitive radiotherapy for non-small cell lung cancer

    DEFF Research Database (Denmark)

    Schytte, Tine; Nielsen, Tine Bjørn; Brink, Carsten

    2014-01-01

    , and occurrence of distant metastasis. It is challenging to evaluate loco-regional control after definitive radiotherapy for NSCLC since it is difficult to distinguish between radiation-induced damage to the lung tissue and tumour progression/recurrence. In addition it may be useful to distinguish between...... intrapulmonary failure and mediastinal failure to be able to optimize radiotherapy in order to improve loco-regional control even though it is not easy to discriminate between the two sites of failure. Material and methods. This study is a retrospective analysis of 331 NSCLC patients treated with definitive...... with mediastinal relapse. Conclusion. We conclude that focus should be on increasing doses to intrapulmonary tumour volume, when dose escalation is applied to improve local tumour control in NSCLC patients treated with definitive radiotherapy, since most recurrences are located here....

  8. An overview of loco-regional treatments in patients and mouse models for hepatocellular carcinoma.

    Science.gov (United States)

    Bimonte, Sabrina; Barbieri, Antonio; Palaia, Raffaele; Leongito, Maddalena; Albino, Vittorio; Piccirillo, Mauro; Arra, Claudio; Izzo, Francesco

    2015-01-01

    Hepatocellular carcinoma is a highly aggressive malignancy and is the third leading cause of cancer-related deaths worldwide. Although surgery is currently considered the most effective curative treatment for this type of cancer, it is note that most of patients have a poor prognosis due to chemioresistence and tumor recurrence. Loco-regional therapies, including radiofrequency ablation, surgical resection and transcatheter arterial chemoembolization play a major role in the clinical management of hepatocellular carcinoma. In order to improve the treatment outcome of patients diagnosed with this disease, several in vivo studies by using different techniques on cancer mouse models have been performed. This review will focus on the latest papers on the efficacy of loco-regional therapy and combined treatments in patients and mouse models of hepatocellular carcinoma.

  9. Correction of Magnetic Optics and Beam Trajectory Using LOCO Based Algorithm with Expanded Experimental Data Sets

    Energy Technology Data Exchange (ETDEWEB)

    Romanov, A.; Edstrom, D.; Emanov, F. A.; Koop, I. A.; Perevedentsev, E. A.; Rogovsky, Yu. A.; Shwartz, D. B.; Valishev, A.

    2017-03-28

    Precise beam based measurement and correction of magnetic optics is essential for the successful operation of accelerators. The LOCO algorithm is a proven and reliable tool, which in some situations can be improved by using a broader class of experimental data. The standard data sets for LOCO include the closed orbit responses to dipole corrector variation, dispersion, and betatron tunes. This paper discusses the benefits from augmenting the data with four additional classes of experimental data: the beam shape measured with beam profile monitors; responses of closed orbit bumps to focusing field variations; betatron tune responses to focusing field variations; BPM-to-BPM betatron phase advances and beta functions in BPMs from turn-by-turn coordinates of kicked beam. All of the described features were implemented in the Sixdsimulation software that was used to correct the optics of the VEPP-2000 collider, the VEPP-5 injector booster ring, and the FAST linac.

  10. Shock compression of glow discharge polymer (GDP): density functional theory (DFT) simulations and experiments on Sandia's Z-machine

    Science.gov (United States)

    Mattsson, Thomas R.; Cochrane, K. R.; Ao, T.; Lemke, R. W.; Flicker, D. G.; Schoff, M. E.; Blue, B. E.; Hamel, S.; Herrmann, M. C.

    2015-11-01

    Glow discharge polymer (GDP) is used extensively as capsule/ablation material in inertial confinement fusion (ICF) capsules. Accurate knowledge of the equation of state (EOS) under shock and release is particularly important for high-fidelity design, analysis, and optimization of ICF experiments since the capsule material is subject to several converging shocks as well as release towards the cryogenic fuel. We performed Density Functional Theory (DFT) based quantum molecular dynamics (QMD) simulations, to gain knowledge of the behavior of GDP - including the effect of changes in chemical composition. The shock pressures calculated from DFT are compared experimental data taken on magnetically launched flyer plate impact experiments on at Sandia's Z-machine. Large GDP samples were grown in a planar geometry to improve the sample quality and maintained in a nitrogen atmosphere following manufacturing, thus allowing for a direct comparison to the DFT/QMD simulations. Sandia National Laboratories is a multi program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's NNSA under contract DE-AC04-94AL85000.

  11. Shock compression of glow discharge polymer (GDP): density functional theory (DFT) simulations and experiments on Sandia's Z machine

    Science.gov (United States)

    Cochrane, Kyle R.; Ao, T.; Lemke, R. W.; Hamel, S.; Schoff, M. E.; Blue, B. E.; Herrmann, M. C.; Mattsson, T. R.

    2014-03-01

    Glow discharge polymer (GDP) is used extensively as capsule/ablation material in inertial confinement fusion (ICF) capsules. Accurate knowledge of the equation of state (EOS) under shock and release is particularly important for high-fidelity design, analysis, and optimization of ICF experiments since the capsule material is subject to several converging shocks as well as release towards the cryogenic fuel. We performed Density Functional Theory (DFT) based quantum molecular dynamics (QMD) simulations, to gain knowledge of the behavior of GDP - for example regarding the role of chemical dissociation during shock compression, we find that the dissociation regime along the Hugoniot extends from 50 GPa to 250 GPa. The shock pressures calculated from DFT are compared experimental data taken at Sandia's Z-machine. The GDP samples were grown in a planar geometry to improve the sample quality and maintained in a nitrogen atmosphere following manufacturing, thus allowing for a direct comparison to the DFT/QMD simulations. Sandia National Laboratories is a multi program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's NNSA under contract DE-AC04-94AL85000.

  12. The effects of pore and second-phase particle on the mechanical properties of machining copper matrix from molecular dynamic simulation

    Science.gov (United States)

    Li, Jia; Fang, Qihong; Liu, Bin; Liu, Youwen

    2016-10-01

    The subsurface damage and surface integrity of a spherical diamond indenter sliding against a face-centred cubic copper (100) surface considering the pore and second-phase particle effects is investigated by means of molecular dynamic simulations of nanoindentation followed by nanomachining. In this investigation, we establish an analytical model for pore healing, and provide a criteria to determine whether or not pore can be healed. The results show that with increase of machining distance pore becomes smaller and then closes due to machining-induced compressive stress, resulting in low material damage and strong structure stability. Compared to free pore workpiece, machining force slightly relies upon the existence of pore and second-phase particle while friction coefficient strongly depends on the existence of that. In addition, particle induces work hardening due to Lomere-Cottrel lock and dislocation slip during machining metal matrix composites. It is helpful to understand the relation of machining performance and material parameter for obtaining higher surface integrity and lower subsurface damage during machining porous metals and particle reinforced metal matrix composites.

  13. Machine learning methods for empirical streamflow simulation: a comparison of model accuracy, interpretability, and uncertainty in seasonal watersheds

    Science.gov (United States)

    Shortridge, Julie E.; Guikema, Seth D.; Zaitchik, Benjamin F.

    2016-07-01

    In the past decade, machine learning methods for empirical rainfall-runoff modeling have seen extensive development and been proposed as a useful complement to physical hydrologic models, particularly in basins where data to support process-based models are limited. However, the majority of research has focused on a small number of methods, such as artificial neural networks, despite the development of multiple other approaches for non-parametric regression in recent years. Furthermore, this work has often evaluated model performance based on predictive accuracy alone, while not considering broader objectives, such as model interpretability and uncertainty, that are important if such methods are to be used for planning and management decisions. In this paper, we use multiple regression and machine learning approaches (including generalized additive models, multivariate adaptive regression splines, artificial neural networks, random forests, and M5 cubist models) to simulate monthly streamflow in five highly seasonal rivers in the highlands of Ethiopia and compare their performance in terms of predictive accuracy, error structure and bias, model interpretability, and uncertainty when faced with extreme climate conditions. While the relative predictive performance of models differed across basins, data-driven approaches were able to achieve reduced errors when compared to physical models developed for the region. Methods such as random forests and generalized additive models may have advantages in terms of visualization and interpretation of model structure, which can be useful in providing insights into physical watershed function. However, the uncertainty associated with model predictions under extreme climate conditions should be carefully evaluated, since certain models (especially generalized additive models and multivariate adaptive regression splines) become highly variable when faced with high temperatures.

  14. Radiofrequency Ablation to Treat Loco-Regional Recurrence of Well-Differentiated Thyroid Carcinoma

    OpenAIRE

    Lee, Sun Jin; Jung, So Lyung; Kim, Bum Soo; Ahn, Kook Jin; Choi, Hyun Seok; Lim, Dong Jun; Kim, Min Hee; Bae, Ja Seong; Kim, Min Sik; Jung, Chan Kwon; Chong, Se Min

    2014-01-01

    Objective To evaluate the efficacy of radiofrequency ablation (RFA) in the treatment of loco-regional, recurrent, and well-differentiated thyroid carcinoma. Materials and Methods Thirty-five recurrent well-differentiated thyroid carcinomas (RTC) in 32 patients were treated with RFA, between March 2008 and October 2011. RTCs were detected by regular follow-up ultrasound and confirmed by biopsy. All patients had fewer than 3 RTCs in the neck and were at high surgical risk or refused to undergo ...

  15. Prognostic Factors for Local, Loco-regional and Systemic Recurrence in Early-stage Breast Cancer.

    Science.gov (United States)

    Kümmel, A; Kümmel, S; Barinoff, J; Heitz, F; Holtschmidt, J; Weikel, W; Lorenz-Salehi, F; du Bois, A; Harter, P; Traut, A; Blohmer, J U; Ataseven, B

    2015-07-01

    Aim: The risk of recurrence in breast cancer depends on factors such as treatment but also on the intrinsic subtype. We analyzed the risk factors for local, loco-regional and systemic recurrence, evaluated the differences and analyzed the risk of recurrence for different molecular subtypes. Material and Methods: A total of 3054 breast cancer patients who underwent surgery followed by adjuvant treatment at HSK hospital or Essen Mitte Hospital between 1998 and 2011 were analyzed. Based on immunohistochemical parameters, cancers were divided into the following subgroups: luminal A, luminal B (HER2-), luminal B (HER2+), HER2+ and TNBC (triple negative breast cancer). Results: 67 % of tumors were classified as luminal A, 13 % as luminal B (HER2-), 6 % as luminal B (HER2+), 3 % as HER2+ and 11 % as TNBC. After a median follow-up time of 6.6 years there were 100 local (3.3 %), 32 loco-regional (1 %) and 248 distant recurrences (8 %). Five-year recurrence-free survival for the overall patient collective was 92 %. On multivariate analysis, positive nodal status, TNBC subtype and absence of radiation therapy were found to be independent risk factors for all forms of recurrence. Age loco-regional recurrence was low. In addition to nodal status, subgroup classification was found to be an important factor affecting the risk of recurrence.

  16. Personalization of loco-regional care for primary breast cancer patients (part 1).

    Science.gov (United States)

    Toi, Masakazu; Winer, Eric P; Benson, John R; Inamoto, Takashi; Forbes, John F; von Minckwitz, Gunter; Robertson, John F R; Grobmyer, Stephen R; Jatoi, Ismail; Sasano, Hironobu; Kunkler, Ian; Ho, Alice Y; Yamauchi, Chikako; Chow, Louis W C; Huang, Chiun-Sheng; Han, Wonshik; Noguchi, Shinzaburo; Pegram, Mark D; Yamauchi, Hideko; Lee, Eun-Sook; Larionov, Alexey A; Bevilacqua, Jose L B; Yoshimura, Michio; Sugie, Tomoharu; Yamauchi, Akira; Krop, Ian E; Noh, Dong Young; Klimberg, V Suzanne

    2015-01-01

    ABSTRACT  Kyoto Breast Cancer Consensus Conference, Kyoto, Japan, 18-20 February 2014 The loco-regional management of breast cancer is increasingly complex with application of primary systemic therapies, oncoplastic techniques and genetic testing for breast cancer susceptibility. Personalization of loco-regional treatment is integral to optimization of breast cancer care. Clinical and pathological tumor stage, biological features and host factors influence loco-regional treatment strategies and extent of surgical procedures. Key issues including axillary staging, axillary treatment, radiation therapy, primary systemic therapy (PST), preoperative hormonal therapy and genetic predisposition were identified and discussed at the Kyoto Breast Cancer Consensus Conference (KBCCC2014). In the first of a two part conference scene, consensus recommendations for axillary management are presented and focus on the following topics: indications for completion axillary lymph node dissection in primary surgical patients with ≤2 macrometastases or any sentinel nodal deposits after PST; the timing of sentinel lymph node biopsy in the context of PST; use of axillary irradiation as a component of primary treatment plans and the role of intraoperative node assessment in the post-Z0011 era.

  17. Personalization of loco-regional care for primary breast cancer patients (part 2).

    Science.gov (United States)

    Toi, Masakazu; Winer, Eric P; Benson, John R; Inamoto, Takashi; Forbes, John F; von Minckwitz, Gunter; Robertson, John F R; Grobmyer, Stephen R; Jatoi, Ismail; Sasano, Hironobu; Kunkler, Ian; Ho, Alice Y; Yamauchi, Chikako; Chow, Louis W C; Huang, Chiun-Sheng; Han, Wonshik; Noguchi, Shinzaburo; Pegram, Mark D; Yamauchi, Hideko; Lee, Eun-Sook; Larionov, Alexey A; Bevilacqua, Jose L B; Yoshimura, Michio; Sugie, Tomoharu; Yamauchi, Akira; Krop, Ian E; Noh, Dong Young; Klimberg, V Suzanne

    2015-01-01

    Kyoto Breast Cancer Consensus Conference, Kyoto, Japan, 18-20 February 2014 The loco-regional management of breast cancer is increasingly complex with application of primary systemic therapies, oncoplastic techniques and genetic testing for breast cancer susceptibility. Personalization of loco-regional treatment is integral to optimization of breast cancer care. Clinical and pathological tumor stage, biological features and host factors influence loco-regional treatment strategies and extent of surgical procedures. Key issues including axillary staging, axillary treatment, radiation therapy, primary systemic therapy (PST), preoperative hormonal therapy and genetic predisposition were identified and discussed at the Kyoto Breast Cancer Consensus Conference (KBCCC2014). In the second of a two part conference scene, consensus recommendations for radiation treatment, primary systemic therapies and management of genetic predisposition are reported and focus on the following topics: influence of both clinical response to PST and stage at presentation on recommendations for postmastectomy radiotherapy; use of regional nodal irradiation in selected node-positive patients and those with adverse pathological factors; extent of surgical resection following downstaging of tumors with PST; use of preoperative hormonal therapy in premenopausal women with larger, node-negative luminal A-like tumors and managing increasing demands for contralateral prophylactic mastectomy in patients with a unilateral sporadic breast cancer.

  18. Fine mapping of the chicken congenital loco locus on chromosome 12.

    Science.gov (United States)

    Okumura, Y; Ohtake, T; Uemoto, Y; Sato, S; Sato, S; Kobayashi, E

    2013-12-01

    Congenital loco in chicks is characterized by an apparent lack of control of the muscles of the neck. This disorder is inherited as a simple Mendelian recessive disease, caused by an autosomal recessive gene, lo. To date, there are no reports on the localization of this gene. The objective of this study was therefore to identify the genomic region of the lo locus. The experimental congenital loco population used here were selected from a Rhode Island Red (RIR) line and consisted of six generations, resulting in 124 chickens. A total of 113 DNA samples from offspring of four generations (G3, G4, G5, and G6) were used for genotyping. At first, genome-wide linkage mapping was performed using 122 microsatellite markers on 22 autosomal chromosomes, and the lo locus was mapped to chromosome 12. We then performed fine mapping in two steps on chromosome 12. First, the lo locus was mapped to the interval between GGA12_5 and GGA12_11 using 13 new polymorphic markers. In the second step, fine mapping was performed by adding new families and 11 additional new polymorphic markers. Linkage mapping and haplotype information enabled the localization of the lo locus to a 1.1-Mb region between GGA12_28 and GGA12_30. Genetic markers between GGA12_28 and GGA12_30 may be used to remove the carriers of congenital loco through this RIR line.

  19. Machine learning from computer simulations with applications in rail vehicle dynamics

    Science.gov (United States)

    Taheri, Mehdi; Ahmadian, Mehdi

    2016-05-01

    The application of stochastic modelling for learning the behaviour of a multibody dynamics (MBD) models is investigated. Post-processing data from a simulation run are used to train the stochastic model that estimates the relationship between model inputs (suspension relative displacement and velocity) and the output (sum of suspension forces). The stochastic model can be used to reduce the computational burden of the MBD model by replacing a computationally expensive subsystem in the model (suspension subsystem). With minor changes, the stochastic modelling technique is able to learn the behaviour of a physical system and integrate its behaviour within MBD models. The technique is highly advantageous for MBD models where real-time simulations are necessary, or with models that have a large number of repeated substructures, e.g. modelling a train with a large number of railcars. The fact that the training data are acquired prior to the development of the stochastic model discards the conventional sampling plan strategies like Latin Hypercube sampling plans where simulations are performed using the inputs dictated by the sampling plan. Since the sampling plan greatly influences the overall accuracy and efficiency of the stochastic predictions, a sampling plan suitable for the process is developed where the most space-filling subset of the acquired data with ? number of sample points that best describes the dynamic behaviour of the system under study is selected as the training data. Results indicated that the stochastic modelling technique is effective in improving the computational efficiency of the MBD model without compromising the accuracy of the predictions, although the improvements in the computational efficiency of the technique could not be quantified due to the inefficiencies associated with transferring the data between multiple software packages (SIMPACK, SIMULINK).

  20. Optimization and Simulation of CNC Flywheel Housing Machining Technology%飞轮壳数控加工工艺优化及仿真

    Institute of Scientific and Technical Information of China (English)

    韩旭; 兰海; 王春; 孙治成

    2016-01-01

    In order to cut down the machining cycle time of a flywheel housing production line,the unreasona-ble machining process of the flywheel housing was pointed out,and optimization scheme was put forward through the analysis on the key machining process. In order to verify the optimization results,simulations of the original machining process and the improved process were conducted by using software VERICUT. To en-sure the accuracy of the simulation,setup and configuration on VERICUT was accordance with the actual ma-chine tool and cutters parameters. The simulation result shows that the optimization scheme is correct and rea-sonable and capable of shorten the machining cycle time of the flywheel housing.%为了缩短某飞轮壳生产线时间节拍,对其瓶颈工序数控加工工艺进行分析,确定了其工艺不合理之处,提出了加工工艺优化方案.为了验证优化方案的合理性,运用了VERICUT数控加工软件对原加工工艺和改进工艺进行仿真模拟,并按照实际机床和刀具参数对VERICUT进行相应设置,保证了仿真的准确性.仿真结果证明优化方案正确可行,能够大幅缩短加工生产节拍.

  1. Studies of the Machine Induced Background, simulations for the design of the Beam Condition Monitor and implementation of the Inclusive $\\phi$ Trigger at the LHCb experiment at CERN

    CERN Document Server

    Lieng, Magnus

    2011-01-01

    LHCb is one of the four major experiments of the LHC at CERN, built to perform precision measurements of CP violation and rare decays. In order to protect the sensitive elements of the experiment from adverse beam conditions the Beam Condition Monitor has been created. Such conditions increase the particle flux arriving from the LHC, known as Machine Induced Background. These particles interfere with the experiment, for example through the physics trigger. In this thesis software development and simulations for the design and validation of the Beam Condition Monitor is shown, ranging from LHCb-specific algorithm implementation to beam dump threshold determination. Furthermore, software development in order to attain a complete simulation chain of machine induced background is shown. The results of these simulations are compared to early data collected at LHCb. Lastly, the development and implementation of the Inclusive $\\phi$ trigger line for the High Level Trigger is presented. This line aims to reconstruct ...

  2. Research on machine tool design and simulation based on virtual prototype%基于虚拟样机的机床设计与仿真研究

    Institute of Scientific and Technical Information of China (English)

    高清冉; 孙海燕; 李海洪; 周晓亮

    2009-01-01

    为了提高机床的设计水平,将虚拟样机技术引入机床的设计开发过程,通过虚拟样机技术的使用辅助设计人员进行方案分析.利用三维造型软件SolidWorks实现虚拟样机模型的建立,应用对象的链接与嵌套技术进行数控加工仿真、刀具轨迹显示、自动换刀和毛坯的自动设计,采用仿真软件ADAMS实现了该机床的动力学分析和仿真.将上述方法应用于并联机床的具体设计中,计算机仿真结果验证了理论模型的合理性,进而验证了设计的正确性和可靠性.%For the sake of enhancing the designing level of ma-chine tools, the virtual prototype technology was introduced into the designing development process of machine tools. By means of em- ploying virtual prototype technology the designers was assisted in carrying out the scheme analysis. Utilizating the 3D modelling soft-ware SolidWorks, the establishment of virtual prototype model was realized. By applying the linkage of object and inlaid technology to carrying out numerical controlled machining simulation, display of cutter track, automatic tool change and automatic design of blank. The dynamics analysis and simulation of this machine tool were car-ried out by adopting the simulation software ADAMS. Let the above stated method be applied to a concrete design of parallel machine tools, the result of computer simulation verified the rationality of theoretical model and then testified the correctness and reliability of the design.

  3. Simultaneous Five-axis Motion for Identifying Geometric Deviations Through Simulation in Machining Centers with a Double Pivot Head

    Science.gov (United States)

    Dassanayake, Muditha; Yamamoto, Ken; Tsutsumi, Masaomi; Saito, Akinori; Mikami, Shigetaka

    In this paper, simultaneous five-axis control motions were newly proposed to identify the ten inherent deviations to double pivot head type five-axis machines. This motion was designed for the application of a ball bar to the measurements. The ball bar can be applied to the motion by changing the ball bar's sensitive direction in the axial, radial and tangential directions in relation to the A-axis rotation. All the three ball bar settings can be changed in a single arrangement, with a magnetic clamp fixed onto the main spindle. This leads to reduce the setting errors and setting time as well. The ten deviations are identified by using three measurements, two of which are taken in the axial direction motion while the third is extracted using the tangential or radial direction motion. From the axial direction motion, seven deviations are estimated; four of these estimations are made using the observation equation while the other three are made using simple geometric relations. The remaining three of the ten deviations are determined by using tangential or radial motion. The validity of the proposed method is confirmed by simulations.

  4. Using machine learning and real-time workload assessment in a high-fidelity UAV simulation environment

    Science.gov (United States)

    Monfort, Samuel S.; Sibley, Ciara M.; Coyne, Joseph T.

    2016-05-01

    Future unmanned vehicle operations will see more responsibilities distributed among fewer pilots. Current systems typically involve a small team of operators maintaining control over a single aerial platform, but this arrangement results in a suboptimal configuration of operator resources to system demands. Rather than devoting the full-time attention of several operators to a single UAV, the goal should be to distribute the attention of several operators across several UAVs as needed. Under a distributed-responsibility system, operator task load would be continuously monitored, with new tasks assigned based on system needs and operator capabilities. The current paper sought to identify a set of metrics that could be used to assess workload unobtrusively and in near real-time to inform a dynamic tasking algorithm. To this end, we put 20 participants through a variable-difficulty multiple UAV management simulation. We identified a subset of candidate metrics from a larger pool of pupillary and behavioral measures. We then used these metrics as features in a machine learning algorithm to predict workload condition every 60 seconds. This procedure produced an overall classification accuracy of 78%. An automated tasker sensitive to fluctuations in operator workload could be used to efficiently delegate tasks for teams of UAV operators.

  5. Method for vibration response simulation and sensor placement optimization of a machine tool spindle system with a bearing defect.

    Science.gov (United States)

    Cao, Hongrui; Niu, Linkai; He, Zhengjia

    2012-01-01

    Bearing defects are one of the most important mechanical sources for vibration and noise generation in machine tool spindles. In this study, an integrated finite element (FE) model is proposed to predict the vibration responses of a spindle bearing system with localized bearing defects and then the sensor placement for better detection of bearing faults is optimized. A nonlinear bearing model is developed based on Jones' bearing theory, while the drawbar, shaft and housing are modeled as Timoshenko's beam. The bearing model is then integrated into the FE model of drawbar/shaft/housing by assembling equations of motion. The Newmark time integration method is used to solve the vibration responses numerically. The FE model of the spindle-bearing system was verified by conducting dynamic tests. Then, the localized bearing defects were modeled and vibration responses generated by the outer ring defect were simulated as an illustration. The optimization scheme of the sensor placement was carried out on the test spindle. The results proved that, the optimal sensor placement depends on the vibration modes under different boundary conditions and the transfer path between the excitation and the response.

  6. When Machines Design Machines!

    DEFF Research Database (Denmark)

    2011-01-01

    Until recently we were the sole designers, alone in the driving seat making all the decisions. But, we have created a world of complexity way beyond human ability to understand, control, and govern. Machines now do more trades than humans on stock markets, they control our power, water, gas...... and food supplies, manage our elevators, microclimates, automobiles and transport systems, and manufacture almost everything. It should come as no surprise that machines are now designing machines. The chips that power our computers and mobile phones, the robots and commercial processing plants on which we...... depend, all are now largely designed by machines. So what of us - will be totally usurped, or are we looking at a new symbiosis with human and artificial intelligences combined to realise the best outcomes possible. In most respects we have no choice! Human abilities alone cannot solve any of the major...

  7. Physics-based simulation modeling and optimization of microstructural changes induced by machining and selective laser melting processes in titanium and nickel based alloys

    Science.gov (United States)

    Arisoy, Yigit Muzaffer

    Manufacturing processes may significantly affect the quality of resultant surfaces and structural integrity of the metal end products. Controlling manufacturing process induced changes to the product's surface integrity may improve the fatigue life and overall reliability of the end product. The goal of this study is to model the phenomena that result in microstructural alterations and improve the surface integrity of the manufactured parts by utilizing physics-based process simulations and other computational methods. Two different (both conventional and advanced) manufacturing processes; i.e. machining of Titanium and Nickel-based alloys and selective laser melting of Nickel-based powder alloys are studied. 3D Finite Element (FE) process simulations are developed and experimental data that validates these process simulation models are generated to compare against predictions. Computational process modeling and optimization have been performed for machining induced microstructure that includes; i) predicting recrystallization and grain size using FE simulations and the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model, ii) predicting microhardness using non-linear regression models and the Random Forests method, and iii) multi-objective machining optimization for minimizing microstructural changes. Experimental analysis and computational process modeling of selective laser melting have been also conducted including; i) microstructural analysis of grain sizes and growth directions using SEM imaging and machine learning algorithms, ii) analysis of thermal imaging for spattering, heating/cooling rates and meltpool size, iii) predicting thermal field, meltpool size, and growth directions via thermal gradients using 3D FE simulations, iv) predicting localized solidification using the Phase Field method. These computational process models and predictive models, once utilized by industry to optimize process parameters, have the ultimate potential to improve performance of

  8. Path planning of multi head drilling machine and simulation software development%多头钻床轨迹规划和仿真软件的开发

    Institute of Scientific and Technical Information of China (English)

    梁全

    2011-01-01

    针对多主轴头的数控钻床钻孔路径规划问题进行了分析,在充分考虑机床的机械结构和加工效率要求的前提下,提出了多头数控钻床的钻孔路径规划算法.首先分析了DXF文件的结构,接下来将二维空间中的孔群分解成一维空间中的孔群进行钻孔路径的规划.为了验证算法和真实加工的可行性,还开发了仿真软件,针对某工程中的某管板类零件规划了钻孔路径,并进行了仿真加工.仿真加工结果证明,开发的算法正确可靠,可以用来进行多头钻的钻孔路径规划.%This paper analyzed the problem of drilling path planning about CNC drill machine. Under the premise of taking account of the mechanical structure and processing machine efficiency requirements, promoting path planning algorithm about multi spindles CNC drilling machine. First, this paper analyzed the structure of DXF file, then dividing the two dimensional space hole-group into one dimensional hole-group to plan. In order to verify the feasibility of processing algorithms and real application, this paper also developed simulation software, planned drilling path for a tube plate in actual application and made simulation machining. Simulation results show that the algorithm is accurate and can be used in drilling path planning in multi spindle CNC drilling machine.

  9. Image Compression Ratio Control Based on LOCO-Ⅰ Algorithm%基于LOCO-Ⅰ算法的图像压缩比控制

    Institute of Scientific and Technical Information of China (English)

    陈益刚; 邓家先; 谢凯明

    2015-01-01

    在认真研究LOCO-Ⅰ算法的基础上,深入分析了失真控制参数Near对图像压缩比和重建质量的影响,通过对该算法中的Near进行实时动态调整,实现了对图像近无损压缩的压缩比控制,进而可以根据需求来控制图片大小进行压缩.仿真结果表明,提出的压缩比控制方案收敛性较好,输出码流稳定,在满足目标压缩比时重建图像质量较原一阶压缩比控制方案提高了0.5 dB左右.

  10. Simulation of radiation transport using MCNP for a teletherapy machine; Simulacion del transporte de radiacion usando MCNP para una maquina de teleterapia

    Energy Technology Data Exchange (ETDEWEB)

    Flores O, F.E.; Mireles G, F.; Davila R, J.I.; Pinedo V, J.L.; Risorios M, C.; Lopez del Rio, H. [UAZ, Unidad Academica de Estudios Nucleares, 98068 Zacatecas (Mexico)

    2008-07-01

    The MCNP code is used to simulate the radiation transport taking as tools the transport physics of each particle, either photon, neutron or electron, and the generation of random numbers. Developed in the Los Alamos National Laboratory, this code has been used thoroughly with great success, because the results of the simulations are broadly validated with representative experiments. In the one present work the room of radiotherapy of the Institute Zacatecano of the Tumor it is simulated, located in the city of Zacatecas where one is Theratron 780C machine manufactured by MSD Nordion, with the purpose of estimating the contribution to the dose that would be received in different points of the structure, included three directly under the source. Three results of analytical calculations for points located at different distances from the source are presented, and they are compared against those obtained by the simulation. Its are also presented results for the simulation of 10 points more distributed around the source. (Author)

  11. Reactive Turing machines

    NARCIS (Netherlands)

    Baeten, J.C.M.; Luttik, B.; Tilburg, P.J.A. van

    2013-01-01

    We propose reactive Turing machines (RTMs), extending classical Turing machines with a process-theoretical notion of interaction, and use it to define a notion of executable transition system. We show that every computable transition system with a bounded branching degree is simulated modulo diverge

  12. An extreme learning machine model for the simulation of monthly mean streamflow water level in eastern Queensland.

    Science.gov (United States)

    Deo, Ravinesh C; Şahin, Mehmet

    2016-02-01

    A predictive model for streamflow has practical implications for understanding the drought hydrology, environmental monitoring and agriculture, ecosystems and resource management. In this study, the state-or-art extreme learning machine (ELM) model was utilized to simulate the mean streamflow water level (Q WL) for three hydrological sites in eastern Queensland (Gowrie Creek, Albert, and Mary River). The performance of the ELM model was benchmarked with the artificial neural network (ANN) model. The ELM model was a fast computational method using single-layer feedforward neural networks and randomly determined hidden neurons that learns the historical patterns embedded in the input variables. A set of nine predictors with the month (to consider the seasonality of Q WL); rainfall; Southern Oscillation Index; Pacific Decadal Oscillation Index; ENSO Modoki Index; Indian Ocean Dipole Index; and Nino 3.0, Nino 3.4, and Nino 4.0 sea surface temperatures (SSTs) were utilized. A selection of variables was performed using cross correlation with Q WL, yielding the best inputs defined by (month; P; Nino 3.0 SST; Nino 4.0 SST; Southern Oscillation Index (SOI); ENSO Modoki Index (EMI)) for Gowrie Creek, (month; P; SOI; Pacific Decadal Oscillation (PDO); Indian Ocean Dipole (IOD); EMI) for Albert River, and by (month; P; Nino 3.4 SST; Nino 4.0 SST; SOI; EMI) for Mary River site. A three-layer neuronal structure trialed with activation equations defined by sigmoid, logarithmic, tangent sigmoid, sine, hardlim, triangular, and radial basis was utilized, resulting in optimum ELM model with hard-limit function and architecture 6-106-1 (Gowrie Creek), 6-74-1 (Albert River), and 6-146-1 (Mary River). The alternative ELM and ANN models with two inputs (month and rainfall) and the ELM model with all nine inputs were also developed. The performance was evaluated using the mean absolute error (MAE), coefficient of determination (r (2)), Willmott's Index (d), peak deviation (P dv), and Nash

  13. Loco-regional cancer drug therapy: present approaches and rapidly reversible hydrophobization (RRH) of therapeutic agents as the future direction.

    Science.gov (United States)

    Budker, Vladimir G; Monahan, Sean D; Subbotin, Vladimir M

    2014-12-01

    Insufficient drug uptake by solid tumors remains the major problem for systemic chemotherapy. Many studies have demonstrated anticancer drug effects to be dose-dependent, although dose-escalation studies have resulted in limited survival benefit with increased systemic toxicities. One solution to this has been the idea of loco-regional drug treatments, which offer dramatically higher drug concentrations in tumor tissues while minimizing systemic toxicity. Although loco-regional delivery has been most prominent in cancers of the liver, soft tissues and serosal peritoneal malignancies, survival benefits are very far from desirable. This review discusses the evolution of loco-regional treatments, the present approaches and offers rapidly reversible hydrophobization of drugs as the new future direction.

  14. Electrical machines & drives

    CERN Document Server

    Hammond, P

    1985-01-01

    Containing approximately 200 problems (100 worked), the text covers a wide range of topics concerning electrical machines, placing particular emphasis upon electrical-machine drive applications. The theory is concisely reviewed and focuses on features common to all machine types. The problems are arranged in order of increasing levels of complexity and discussions of the solutions are included where appropriate to illustrate the engineering implications. This second edition includes an important new chapter on mathematical and computer simulation of machine systems and revised discussions o

  15. Usability of a virtual reality environment simulating an automated teller machine for assessing and training persons with acquired brain injury

    Directory of Open Access Journals (Sweden)

    Li Teresa HY

    2010-04-01

    Full Text Available Abstract Objective This study aimed to examine the usability of a newly designed virtual reality (VR environment simulating the operation of an automated teller machine (ATM for assessment and training. Design Part I involved evaluation of the sensitivity and specificity of a non-immersive VR program simulating an ATM (VR-ATM. Part II consisted of a clinical trial providing baseline and post-intervention outcome assessments. Setting A rehabilitation hospital and university-based teaching facilities were used as the setting. Participants A total of 24 persons in the community with acquired brain injury (ABI - 14 in Part I and 10 in Part II - made up the participants in the study. Interventions In Part I, participants were randomized to receive instruction in either an "early" or a "late" VR-ATM program and were assessed using both the VR program and a real ATM. In Part II, participants were assigned in matched pairs to either VR training or computer-assisted instruction (CAI teaching programs for six 1-hour sessions over a three-week period. Outcome Measures Two behavioral checklists based on activity analysis of cash withdrawals and money transfers using a real ATM were used to measure average reaction time, percentage of incorrect responses, level of cues required, and time spent as generated by the VR system; also used was the Neurobehavioral Cognitive Status Examination. Results The sensitivity of the VR-ATM was 100% for cash withdrawals and 83.3% for money transfers, and the specificity was 83% and 75%, respectively. For cash withdrawals, the average reaction time of the VR group was significantly shorter than that of the CAI group (p = 0.021. We found no significant differences in average reaction time or accuracy between groups for money transfers, although we did note positive improvement for the VR-ATM group. Conclusion We found the VR-ATM to be usable as a valid assessment and training tool for relearning the use of ATMs prior to real

  16. Sensitivity study using machine learning algorithms on simulated r-mode gravitational wave signals from newborn neutron stars

    CERN Document Server

    Mytidis, Antonis; Panagopoulos, Orestis P; Whiting, Bernard

    2015-01-01

    This is a follow-up sensitivity study on r-mode gravitational wave signals from newborn neutron stars illustrating the applicability of machine learning algorithms for the detection of long-lived gravitational-wave transients. In this sensitivity study we examine three machine learning algorithms (MLAs): artificial neural networks (ANNs), support vector machines (SVMs) and constrained subspace classifiers (CSCs). The objective of this study is to compare the detection efficiency that MLAs can achieve with the efficiency of conventional detection algorithms discussed in an earlier paper. Comparisons are made using 2 distinct r-mode waveforms. For the training of the MLAs we assumed that some information about the distance to the source is given so that the training was performed over distance ranges not wider than half an order of magnitude. The results of this study suggest that machine learning algorithms are suitable for the detection of long-lived gravitational-wave transients and that when assuming knowle...

  17. Embedded software simulation testing environment based on virtual machine%基于虚拟机的嵌人式软件仿真测试环境

    Institute of Scientific and Technical Information of China (English)

    殷永峰; 刘斌; 王志

    2011-01-01

    In order to enhance the quality and reliability of embedded software, an embedded software simulation testing environment based on virtual machine was proposed. The virtual machine technology was introduced into the simulation testing field of embedded software, and the constitution principle of embedded software simulation testing environment was introduced. In addition, the virtual machine technology was analyzed, and an embedded software simulation testing virtual machine (ESSTVM) based on an extended program-transplantation virtual machine model was proposed. And the design scheme for the memory management and instruction system was presented. The ESSTVM was applied to the design of avionics embedded software simulation testing environment (AESSTE), and the system structure of the testing environment was studied. Moreover, the design and realization of both testing development and testing execution systems were elaborated, and the transportability of AESSTE was analyzed. The analysis results show that the proposed method can effectively improve the universality, transportability and maintainability of embedded software testing environment.%为了提高嵌入式软件的质量和可靠性,提出了一种基于虚拟机的嵌入式软件仿真测试环境.将虚拟机技术引入到嵌入式软件仿真测试领域中,介绍了嵌入式软件仿真测试环境的构成原理,并对虚拟机技术进行了分析,提出一种基于程序移植虚拟机模型扩展的嵌入式软件仿真测试虚拟机(ESSTVM),给出了内存管理和指令系统的设计方案.将ESSTVM应用到航电嵌入式软件系统测试环境AESSTE设计中,研究了该测试环境的体系结构,阐述了测试开发系统及测试执行系统的设计与实现,并对AESSTE的可移植性进行了分析.分析结果表明,该方法能有效提高嵌入式软件测试环境的通用性、可移植性和可维护性.

  18. Study on Temperature and Synthetic Compensation of Piezo-Resistive Differential Pressure Sensors by Coupled Simulated Annealing and Simplex Optimized Kernel Extreme Learning Machine.

    Science.gov (United States)

    Li, Ji; Hu, Guoqing; Zhou, Yonghong; Zou, Chong; Peng, Wei; Alam Sm, Jahangir

    2017-04-19

    As a high performance-cost ratio solution for differential pressure measurement, piezo-resistive differential pressure sensors are widely used in engineering processes. However, their performance is severely affected by the environmental temperature and the static pressure applied to them. In order to modify the non-linear measuring characteristics of the piezo-resistive differential pressure sensor, compensation actions should synthetically consider these two aspects. Advantages such as nonlinear approximation capability, highly desirable generalization ability and computational efficiency make the kernel extreme learning machine (KELM) a practical approach for this critical task. Since the KELM model is intrinsically sensitive to the regularization parameter and the kernel parameter, a searching scheme combining the coupled simulated annealing (CSA) algorithm and the Nelder-Mead simplex algorithm is adopted to find an optimal KLEM parameter set. A calibration experiment at different working pressure levels was conducted within the temperature range to assess the proposed method. In comparison with other compensation models such as the back-propagation neural network (BP), radius basis neural network (RBF), particle swarm optimization optimized support vector machine (PSO-SVM), particle swarm optimization optimized least squares support vector machine (PSO-LSSVM) and extreme learning machine (ELM), the compensation results show that the presented compensation algorithm exhibits a more satisfactory performance with respect to temperature compensation and synthetic compensation problems.

  19. Flow Field Simulation and Machining Experiment of Flank Milling Blasting Erosion Arc Machining%侧铣式高速电弧放电加工的极间流场仿真及加工试验

    Institute of Scientific and Technical Information of China (English)

    洪汉; 顾琳; 徐辉; 赵万生

    2015-01-01

    To extend the application of blasting erosion arc machining, a new arc machining process-flank milling blasting erosion arc machining is proposed, which can process continuous curved surfaces and ruled surfaces. Compared to other processes which utilize arc to machine, flank milling blasting erosion arc machining malnly uses the flank of its electrode to remove workpiece material. It can implement machining of complex surfaces, cavities with large radius of curvature, slots and passages as well. The hole array distributed on the side wall and the rotary motion of the electrode enhance the flushing in the inter electrode gap, combining both mechanisms of hydrodynamic arc breaking mechanism and mechanical moving arc breaking mechanism, thereby obtalning high material removal rate. In order to explore the influence of flushing on machining performance of flank milling blasting erosion arc machining, the inter electrode gap flow models of different electrodes and different inlet pressure are built for simulations. Meanwhile, the machining experiments are conducted. Both simulation and experiments indicate that the increase of number of flushing holes lead to a better machining performance while the inlet pressure kept at 1.6 MPa. It attributes to the improvement of the inter electrode gap flow field, thus malntalning better arcing state. Experiments demonstrate that the material removal rate can reach 4 095 mm3/min and the relative tool wear ratio malntalned below 2.5%while the peak current is 400 A. The passage of turbine is machined to demonstrate the feasibility of flank milling blasting erosion arc machining.%在高速电弧放电加工方法的基础上提出一种用于加工连续曲面、直纹面等的新型加工工艺——侧铣式高速电弧放电加工方法。与其他利用电弧进行加工的工艺方法相比,侧铣式高速电弧放电加工主要利用电极的侧面进行电弧蚀除加工,可用于加工各种复杂曲面和曲率半径较

  20. Gall bladder carcinoma: Aggressive malignancy with protean loco-regional and distant spread.

    Science.gov (United States)

    Dwivedi, Amit Nandan Dhar; Jain, Shivi; Dixit, Ruhi

    2015-03-16

    The most common malignancy of biliary tract is gallbladder cancer (GBC) which is the third most common cancer in gastrointestinal tract. It is a lethal disease for most patients in spite of growing awareness and improved diagnostic techniques. GBC has a very poor prognosis and the 5 year survival rate is loco-regional rather than distant. It spreads by lymphatic, vascular, neural, intraperitoneal, and intraductal routes. Sonography is usually the most common imaging test to evaluate symptoms of biliary tract disease including suspected GC. With recent advances in imaging modalities like multi-detector computed tomography (CT) scanners, magnetic resonance imaging-positron emission tomography/CT diagnosis of gallbladder cancer has improved. Studies have also targeted molecular and genetic pathways. Treatment options have included extended and radical surgeries and adjuvant chemotherapy. This review article deals in detail with important aspects of carcinoma gallbladder and its manifestations and challenges. Role of various imaging modalities in characterization and accurate staging has been discussed. The loco-regional spread of this aggressive malignancy is dealt explicitly.

  1. Treatment for isolated loco-regional recurrence of gastric adenocarcinoma: Does surgery play a role?

    Institute of Scientific and Technical Information of China (English)

    Fabio Carboni; Pasquale Lepiane; Roberto Santoro; Riccardo Lorusso; Pietro Mancini; Massimo Carlini; Eugenio Santoro

    2005-01-01

    AIM: To evaluate the role of surgical treatment for isolated loco-regional recurrences of operated gastric adenocarcinoma.METHODS: Among the 837 patients operated for gastric adenocarcinoma between December 1979and April 2004, 713 (85%) underwent resection with curative intent. A retrospective review of a prospectively collected gastric cancer database was carried out.Overall recurrence rate was 44% (315 cases), with 75%occurring within the first 2 years from the operation.Isolated L-R recurrences were observed in 38 (12%)patients. Symptomatic lesions were observed in 27(71%).RESULTS: Six (16%) patients were macroscopically resected with curative intent. The recurrence was located in the gastric stump after a STG in three patients, in theesophagojejunal anastomosis after a TG in two patients and in the gastric bed after a TG in one patient.Surgical procedures consisted of three secondary TG, two esophagojejunal resection and one excision of an extraluminal recurrence. Postoperative complications occurred in two patients (33%), including one anastomotic leakage and one hemorrhage. The latter patient died of sepsis 35 d after the surgery (mortality rate 17%). All patients died of recurrent gastric cancer:2 within 1 year from surgery (8 and 11 mo, respectively),2 after 16 and 17 mo respectively and 1 after 28 mo from the second operation.CONCLUSION: Surgery plays a very limited role in the treatment for isolated loco-regional recurrence of gastric adenocarcinoma.

  2. 基于ADAMS的步行爬坡机仿真分析%Simulation Analysis of Walking and Climbing Machine Based on ADAMS

    Institute of Scientific and Technical Information of China (English)

    刘冬梅; 杨杭旭

    2014-01-01

    Presently, it is mostly large wheel or caterpillar-type mechanical equipment that is used for transportation operation in the complex environment in mountainous and forest areas. These large machines have such typical shortcomings as large power consumption,poor mobility,low working efficiency,poor balance and insufficient obstacle crossing and climbing ability. In order to solve the above problems,a new type of walking climbing machine is designed, with a virtual prototype established based on Pro/E,with ADAMS used to simulate the movement of the walking climbing machine,simulation results verifying the feasibility of the design.%在山林地区复杂环境中进行运输作业大多使用轮式或履带式大型机械设备,这些设备普遍存在功率消耗大、机动性差、工作效率低,自身平衡性差、越障和爬坡能力不足等问题。为解决这些问题,设计了一种新型的步行爬坡机,并利用Pro/E建立其虚拟样机,采用ADAMS对其运动过程进行仿真,仿真结果验证了设计的可行性。

  3. Simulated annealing and metaheuristic for randomized priority search algorithms for the aerial refuelling parallel machine scheduling problem with due date-to-deadline windows and release times

    Science.gov (United States)

    Kaplan, Sezgin; Rabadi, Ghaith

    2013-01-01

    This article addresses the aerial refuelling scheduling problem (ARSP), where a set of fighter jets (jobs) with certain ready times must be refuelled from tankers (machines) by their due dates; otherwise, they reach a low fuel level (deadline) incurring a high cost. ARSP is an identical parallel machine scheduling problem with release times and due date-to-deadline windows to minimize the total weighted tardiness. A simulated annealing (SA) and metaheuristic for randomized priority search (Meta-RaPS) with the newly introduced composite dispatching rule, apparent piecewise tardiness cost with ready times (APTCR), are applied to the problem. Computational experiments compared the algorithms' solutions to optimal solutions for small problems and to each other for larger problems. To obtain optimal solutions, a mixed integer program with a piecewise weighted tardiness objective function was solved for up to 12 jobs. The results show that Meta-RaPS performs better in terms of average relative error but SA is more efficient.

  4. Design of Sugarcane Peeling Machine

    Directory of Open Access Journals (Sweden)

    Ge Xinfeng

    2015-02-01

    Full Text Available In order to solve the problem that appeared in hand peeling sugarcane, the sugarcane peeling machine is designed, the sugarcane peeling machine includes motor, groove wheel, cutting room, slider crank mechanism, reducer (including belt drive, chain drive and so on. The designed sugarcane peeling machine is simulated, the results show that the sugarcane peeling machine can peel sugarcane successfully with convenient, fast and uniform.

  5. Feature Recognition for Virtual Machining

    OpenAIRE

    Xú, Shixin; Anwer, Nabil; Qiao, Lihong

    2014-01-01

    International audience; Virtual machining uses software tools to simulate machining processes in virtual environments ahead of actual production. This paper proposes that feature recognition techniques can be applied in the course of virtual machining, such as identifying some process problems, and presenting corresponding correcting advices. By comparing with the original CAD model, form errors of the machining features can be found. And then corrections are suggested to process designers. T...

  6. Study on the Simulation of Brush Stubble Machines Trafficability on Sand%灌木平茬机沙地通过性仿真研究

    Institute of Scientific and Technical Information of China (English)

    刘洁; 王猛猛; 陈忠加; 刘旭东

    2015-01-01

    为研究灌木平茬机在科尔沁沙地的通过性能,基于ADAMS/ATV建立了其虚拟样机模型及符合沙地特性的平地、坡路、垂直障碍、凹坑、正弦路面等虚拟地形,进行了灌木平茬机在典型路面上行驶的仿真分析。结果表明,灌木平茬机能够平稳通过所建立的虚拟地形,在沙地上具有较好的通过性能,转向平稳。根据仿真结果确定灌木平茬机主动轮的最佳直径为280 mm、转向半径为0.75 m。%In order to study the trafficability of brush stubble machines in Horqin sandy land , a virtual prototype model and virtual terrains ( flat, slope, vertical obstacle, pits and sine wave road surface) that are consistent with the characteristics of the sandy land are established to conduct simulation analysis of the trafficability of brush stubble machines on typical road surfaces, with the result showing that brush stubble machines can cross the virtual terrains smoothly, indicating good traffica-bility and stable steering performance on the sandy land. Based on the simulation result, the optimal diameter and steering radius of the driving wheels of brush stubble machines are 280 mm and 0.75 m respectively.

  7. The Emergence of New Paradigms in Student-University Relations: From In Loco Parentis to Bystander to Facilitator.

    Science.gov (United States)

    Bickel, Robert D.; Lake, Peter F.

    1997-01-01

    University liability is in transition; its role changing from a parental/custodial "in loco parentis" model (and then a bystander role) to a new model of facilitator. The university enjoys a position of authority and respect, while exercising control more subtly than in the mid-1990s. At the same time, universities may be unable to claim the same…

  8. Lacuna in the Practice of In-Loco-Parentis in Nigerian Schools: The Pot Calling the Kettle Black

    Science.gov (United States)

    Igbinedion, Doye Angela; Nwogu, Uzoma Jonah; Abraham, Nath M.

    2016-01-01

    The principle of in-loco-parentis allows the teachers to assume the responsibilities of a parent in discharging their duties in school. Based on this same principle, parents also have the right to sue teachers, school management, or the government for negligence, recklessness and other practices which do not depict the proper practice of…

  9. Simulations of Carnival Rides and Rube Goldberg Machines for the Visualization of Concepts of Statics and Dynamics

    Science.gov (United States)

    Howard, William; Williams, Richard; Yao, Jason

    2010-01-01

    Solid modeling is widely used as a teaching tool in summer activities with high school students. The addition of motion analysis allows concepts from statics and dynamics to be introduced to students in both qualitative and quantitative ways. Two sets of solid modeling projects--carnival rides and Rube Goldberg machines--are shown to allow the…

  10. Simulations of Carnival Rides and Rube Goldberg Machines for the Visualization of Concepts of Statics and Dynamics

    Science.gov (United States)

    Howard, William; Williams, Richard; Yao, Jason

    2010-01-01

    Solid modeling is widely used as a teaching tool in summer activities with high school students. The addition of motion analysis allows concepts from statics and dynamics to be introduced to students in both qualitative and quantitative ways. Two sets of solid modeling projects--carnival rides and Rube Goldberg machines--are shown to allow the…

  11. 基于MATLAB/Simulink的无刷双馈电机的数学仿真%Mathematical Simulation of Brushless Doubly-fed Machine by MATLAB/Simulink

    Institute of Scientific and Technical Information of China (English)

    侯春

    2015-01-01

    建立了无刷双馈电机的模型 ,对其开环特性进行了分析 ,并对无刷双馈电机异步、同步通用的机械特性进行了仿真验证 ;通过开环系统仿真验证了模型的正确性 ,为下一步闭环系统的仿真与设计做好铺垫.%The model of a brushless doubly-fed machine is set up ,the open-loop characteristics of the brushless doubly-fed are ana-lyzed ,and the universal mechanical characteristics of the brushless doubly-fed machine are simulated .The system can work in both single fed mode and double fed mode ,the model is verified to be correct by open loop system simulation ,to lay the fundation for the next step of the closed-loop system simulation .

  12. Intelligent simulated annealing algorithm applied to the optimization of the main magnet for magnetic resonance imaging machine; Algoritmo simulated annealing inteligente aplicado a la optimizacion del iman principal de una maquina de resonancia magnetica de imagenes

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Lopez, Hector [Universidad de Oriente, Santiago de Cuba (Cuba). Centro de Biofisica Medica]. E-mail: hsanchez@cbm.uo.edu.cu

    2001-08-01

    This work describes an alternative algorithm of Simulated Annealing applied to the design of the main magnet for a Magnetic Resonance Imaging machine. The algorithm uses a probabilistic radial base neuronal network to classify the possible solutions, before the objective function evaluation. This procedure allows reducing up to 50% the number of iterations required by simulated annealing to achieve the global maximum, when compared with the SA algorithm. The algorithm was applied to design a 0.1050 Tesla four coil resistive magnet, which produces a magnetic field 2.13 times more uniform than the solution given by SA. (author)

  13. A decoupling method for turbo-machines aero-acoustic simulations; Une methode de decouplage pour des simulations aeroacoustiques de turbomachines

    Energy Technology Data Exchange (ETDEWEB)

    Couaillier, V.; Rahier, G.; Fotso, P.; Greffeuille, G.

    2002-07-01

    A decoupling method, of flow calculation in upstream of the compressor or the blower, from the whole calculation in a turbo-machine is proposed for the forecast of the acoustic propagation in the air inlet. The interest of this approach is the capacity to slip the calculations in the non linear domain of the flow. The decoupling technic is described in details. Its validation in case of stationary and non stationary flows is presented, as an application example to a turbo-machine. (A.L.B.)

  14. Study and Development of a Simulation System for Dynamic Evaluation on Man-machine Interface Design of Advanced Main Control Rooms of Nuclear Power Plants

    Institute of Scientific and Technical Information of China (English)

    YangXiaojing; ZhouZhiwei; ChenXiaoming; MaYuanle; LiFu; DongYujie; WuWei; OhiTadashi

    2005-01-01

    Since the man-machine interfaces (MMI) of a main control room provide the control platform of a nuclear power plant (NPP),the development of the design quality of MMIs plays a very important role in the operation of a NPP. With the development of digital technology, the development of the advanced main control rooms (AMCRs) has become an inexorable trend. Therefore, the positive and the negative effects of AMCRs on human factors engineering need to be evaluated. For this p~, a simulation system has been studied and developed to quantitatively evaluate a MMI design from the viewpoint of human factors. The simulation system takes advantage of computer simulation technology to simulate an operating process of an interaction between operators and a MMI design under an instruction of an operation procedure of the AMCR of a NPP. Meanwhile, the necessary data are recorded for evaluation. It integrates two editors and one simulator. In the paper, the simulation system is presented in detail. Furthermore, one sample is given to show the results of each of these three subsystems.

  15. Coordination in arm movements during crawl stroke in elite swimmers with a loco-motor disability.

    Science.gov (United States)

    Satkunskiene, Danguole; Schega, Lutz; Kunze, Katrin; Birzinyte, Kristina; Daly, Daniel

    2005-02-01

    The purpose of this study was to investigate selected kinematics parameters of the arm stroke in crawl swimmers with disabilities and to examine the potential use of an index of arm coordination (IdC) to evaluate the stroking technique of swimmers with diverse functional abilities. The degree of overlap in the propulsive phases (superposition model) and lag time between the propulsive phases (catch-up model) was examined in 18 well-trained swimmers with loco-motor disabilities, 9 females and 9 males, from functional classes S3-S10 with S10 being most functional. Based on the results, correct coordination appears to be fundamental to swimming crawl stroke in both able-bodied swimmers as well as swimmers with a disability. Some swimmers with disabilities examined here exhibited extreme values at both ends of the index scale. This might be essential to maintaining balance while swimming when not all limb activity contributes to the forward movement.

  16. Loco-regional administration of nanomedicines for the treatment of lung cancer.

    Science.gov (United States)

    Garrastazu Pereira, Gabriela; Lawson, Amanda Jane; Buttini, Francesca; Sonvico, Fabio

    2016-10-01

    Lung cancer poses one of the most significant challenges to modern medicine, killing thousands every year. Current therapy involves surgical resection supplemented with chemotherapy and radiotherapy due to high rates of relapse. Shortcomings of currently available chemotherapy protocols include unacceptably high levels of systemic toxicity and low accumulation of drug at the tumor site. Loco-regional delivery of nanocarriers loaded with anticancer agents has the potential to significantly increase efficacy, while minimizing systemic toxicity to anticancer agents. Local drug administration at the tumor site using nanoparticulate drug delivery systems can reduce systemic toxicities observed with intravenously administered anticancer drugs. In addition, this approach presents an opportunity for sustained delivery of anticancer drug over an extended period of time. Herein, the progress in the development of locally administered nanomedicines for the treatment of lung cancer is reviewed. Administration by inhalation, intratumoral injection and means of direct in situ application are discussed, the benefits and drawbacks of each modality are explored.

  17. The clinical impact of hypoxia-regulated gene expression in loco-regional gastroesophageal cancer

    DEFF Research Database (Denmark)

    Winther, M.; Alsner, J.; Tramm, T.

    2015-01-01

    squamous cell carcinomas (ESCC) compared with adenocarcinomas of the esophago-gastric junction and the stomach (AC), and was a potential prognostic marker in patients with ESCC. The purpose of the present study was to confirm these results. Materials and Methods: The study population consisted of 152......Purpose/Objective: In a former study (1), the hypoxia gene expression classifier, developed in head and neck squamous cell carcinomas, was applied in 89 patients with loco-regional gastroesophageal cancer (GC). Analysis of the 15 genes was indicative of hypoxia being more profound in esophagus...... were available in 135 patients; ESCC: 89 patients (66%), AC: 43 patients (32%) and other carcinomas: 3 patients (2%). Comparing the cohorts of the original and present study, patient characteristics were similar except for a significantly lower T- and N-stage in the present cohort. Tumor specimens were...

  18. The in loco parentis role of the teacher: A relationship perspective

    Directory of Open Access Journals (Sweden)

    I. J. Oosthuizen

    1992-03-01

    Full Text Available The parent (as the primary educator as well as the teacher (as the secondary' educator functions from independent societal units in their respective roles o f educating the educand The teacher as an in loco parents person has the right on the one hand to maintain order by means of school rules and the punishment o f transgressors and on the other hand has a duty to care for the safety o f the educands. The parent and the teacher share a common goal: the maturing and the development o f the educand. Whilst the nature o f this parent-teacher co-operation is defined as a partnership, it is - taking the technical essentials o f a partnership into account - more o f a voluntary association. This generates the question whether the whole system o f parEnt-teacher co-operation should not be reorganised on the basis o f a true partnership.

  19. Postoperative adjuvant radiotherapy improves loco-regional recurrence of head and neck mucosal melanoma.

    Science.gov (United States)

    Wushou, Alimujiang; Hou, Jing; Zhao, Ya-Jun; Miao, Xin-chao

    2015-05-01

    Primary head and neck mucosal melanoma (HNMM) is a rare tumor with a poor prognosis. Controversy remains as to whether postoperative adjuvant radiotherapy (PORT) achieves a significant benefit in HNMM treatment. Because of the lack of available conclusive prospective data, we performed a systematic review and meta-analysis of all relevant available studies to clarify the benefits of PORT. A comprehensive literature search of PubMed and Google Scholar electronic databases was conducted to collect relevant studies until April 30, 2014. Studies published in the English language comparing surgery alone and surgery plus PORT for HNMM were included, with more than 15 study populations. All statistical analyses were performed using STATA version 12.0. A total of 423 patients were available from eight studies and the median sample size was 53 cases. The median follow-up time was 38.2 months (range 18.3-65.2 months). There was a positive association between PORT and loco-regional recurrence of HNMM (odds ratio [OR] = 0.36, 95% confidence interval [CI] = 0.22-0.60, P = 0.000). No associations were found between the PORT and 3-year and 5-year overall survival (OS) (OR = 1.41, 95% CI = 0.94-2.09, P = 0.093 and OR = 1.06, 95% CI = 0.70-1.61, P = 0.161, respectively). PORT had no impact on 3-year and 5-year OS (hazard ratio [HR] = 1.14, 95% CI = 0.80-1.61, P = 0.472 and HR = 1.34, 95% CI = 0.97-1.85, P = 0.227, respectively). PORT improved loco-regional recurrence of HNMM independent of OS.

  20. Radiofrequency ablation to treat loco-regional recurrence of well-differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Jung, So Lyung; Kim, Bum Soo; Ahn, Kook Jin [Dept. of Radiology, eoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of); and others

    2014-12-15

    To evaluate the efficacy of radiofrequency ablation (RFA) in the treatment of loco-regional, recurrent, and well-differentiated thyroid carcinoma. Thirty-five recurrent well-differentiated thyroid carcinomas (RTC) in 32 patients were treated with RFA, between March 2008 and October 2011. RTCs were detected by regular follow-up ultrasound and confirmed by biopsy. All patients had fewer than 3 RTCs in the neck and were at high surgical risk or refused to undergo repeated surgery. Average number of RFA sessions were 1.3 (range 1-3). Post-RFA biopsy and ultrasound were performed. The mean follow-up period was 30 months. Pre- and post-RFA serum thyroglobulin values were evaluated. Thirty-one patients with 33 RTCs were treated with RFA only, whereas 1 patient with 2 RTCs was treated with RFA followed by surgery. At the last follow-up ultrasound, 31 (94%) of the 33 RTCs treated with RFA alone completely disappeared and the remaining 2 (6%) RTCs showed decreased volume. The largest diameter and volume of the 33 RTCs were markedly decreased by 93.2% (from 8.1 +/- 3.4 mm to 0.6 +/- 1.8 mm, p < 0.001) and 96.4% (from 173.9 +/- 198.7 mm{sup 3} to 6.2 +/- 27.9 mm{sup 3}, p < 0.001), respectively. Twenty of the 21 RTCs evaluated with post-RFA biopsies (95%) were negative for malignancy. One (5%) showed remaining tumor that was removed surgically. The serum thyroglobulin was decreased in 19 of 26 patients (73%). Voice change developed immediately after RFA in 6 patients (19%) and was spontaneously recovered in 5 patients (83%). Radiofrequency ablation can be effective in treating loco-regional, recurrent, and well-differentiated thyroid carcinoma in patients at high surgical risk.

  1. Machine Translation

    Institute of Scientific and Technical Information of China (English)

    张严心

    2015-01-01

    As a kind of ancillary translation tool, Machine Translation has been paid increasing attention to and received different kinds of study by a great deal of researchers and scholars for a long time. To know the definition of Machine Translation and to analyse its benefits and problems are significant for translators in order to make good use of Machine Translation, and helpful to develop and consummate Machine Translation Systems in the future.

  2. Sustainable machining

    CERN Document Server

    2017-01-01

    This book provides an overview on current sustainable machining. Its chapters cover the concept in economic, social and environmental dimensions. It provides the reader with proper ways to handle several pollutants produced during the machining process. The book is useful on both undergraduate and postgraduate levels and it is of interest to all those working with manufacturing and machining technology.

  3. Performance Analysis and Simulation of a Novel Brushless Double Rotor Machine for Power-Split HEV Applications

    Directory of Open Access Journals (Sweden)

    Jingang Bai

    2012-01-01

    Full Text Available A new type of brushless double rotor machine (BDRM is proposed in this paper. The BDRM is an important component in compound-structure permanent-magnet synchronous machine (CS-PMSM systems, which are promising for power-split hybrid electric vehicle (HEV applications. The BDRM can realize the speed adjustment between claw-pole rotor and permanent-magnet rotor without brushes and slip rings. The structural characteristics of the BDRM are described and its magnetic circuit model is built. Reactance parameters of the BDRM are deduced by an analytical method. It is found that the size characteristics of the BDRM are different from those of conventional machines. The new sizing and torque equations are analyzed and the theoretical results are used in the optimization process. Studies of the analytical magnetic circuit and finite element method (FEM model show that the BDRM tends to have high leakage flux and low power factor, and then the method to obtain high power factor is discussed. Furthermore, a practical methodology of the BDRM design is developed, which includes an analytical tool, 2D field calculation and performance evaluation by 3D field calculation. Finally, different topologies of the BDRM are compared and an optimum prototype is designed.

  4. Simulation of the «COSMONAUT-ROBOT» System Interaction on the Lunar Surface Based on Methods of Machine Vision and Computer Graphics

    Science.gov (United States)

    Kryuchkov, B. I.; Usov, V. M.; Chertopolokhov, V. A.; Ronzhin, A. L.; Karpov, A. A.

    2017-05-01

    Extravehicular activity (EVA) on the lunar surface, necessary for the future exploration of the Moon, involves extensive use of robots. One of the factors of safe EVA is a proper interaction between cosmonauts and robots in extreme environments. This requires a simple and natural man-machine interface, e.g. multimodal contactless interface based on recognition of gestures and cosmonaut's poses. When travelling in the "Follow Me" mode (master/slave), a robot uses onboard tools for tracking cosmonaut's position and movements, and on the basis of these data builds its itinerary. The interaction in the system "cosmonaut-robot" on the lunar surface is significantly different from that on the Earth surface. For example, a man, dressed in a space suit, has limited fine motor skills. In addition, EVA is quite tiring for the cosmonauts, and a tired human being less accurately performs movements and often makes mistakes. All this leads to new requirements for the convenient use of the man-machine interface designed for EVA. To improve the reliability and stability of human-robot communication it is necessary to provide options for duplicating commands at the task stages and gesture recognition. New tools and techniques for space missions must be examined at the first stage of works in laboratory conditions, and then in field tests (proof tests at the site of application). The article analyzes the methods of detection and tracking of movements and gesture recognition of the cosmonaut during EVA, which can be used for the design of human-machine interface. A scenario for testing these methods by constructing a virtual environment simulating EVA on the lunar surface is proposed. Simulation involves environment visualization and modeling of the use of the "vision" of the robot to track a moving cosmonaut dressed in a spacesuit.

  5. Tumor markers for early diagnosis for brain metastasis of hepatocellular carcinoma: A case series and literature review for effective loco-regional treatment.

    Science.gov (United States)

    Kamimura, Kenya; Kobayashi, Yuji; Takahashi, Yoshifumi; Abe, Hiroyuki; Kumaki, Daisuke; Yokoo, Takeshi; Kamimura, Hiroteru; Sakai, Norihiro; Sakamaki, Akira; Abe, Satoshi; Takamura, Masaaki; Kawai, Hirokazu; Yamagiwa, Satoshi; Terai, Shuji

    2017-02-01

    Intrahepatic lesions of hepatocellular carcinoma (HCC) have been controlled by significant advances in treatment using loco-regional therapies, including, surgery, ablative therapy, catheter-based chemotherapy, and embolization. Consequently, the number of patients with extrahepatic metastatic lesions has increased. Their prognosis remains poor with approximately loco-regional treatment, including surgical resection and radiation therapy should be performed for better prognosis by preventing re-bleeding from the tumors.

  6. Issues Affecting the Loco-regional and Systemic Management of Patients with Invasive Lobular Carcinoma of the Breast.

    Science.gov (United States)

    Jacobs, Carmel; Clemons, Mark; Addison, Christina; Robertson, Susan; Arnaout, Angel

    2016-01-01

    Invasive lobular carcinoma (ILC) of the breast is the second most common type of invasive breast carcinoma accounting for 8-14% of all breast cancers. Traditional management of ILC has followed similar paradigms as that for invasive ductal carcinoma (IDC). However, ILC represents a pathologically, clinically and biologically unique variant of breast cancer with particular management challenges. These challenges are seen in both the loco-regional management of ILC; where ILC tumors tend to avoid detection and hence present as more clinically advanced and surgically challenging carcinomas, and the systemic management with a unique response pattern to standard systemic therapies. Because of these challenges, the outcome for patients with ILC has likely lagged behind the continued improvements seen in outcome for patients with IDC. Here, we discuss some of the unique challenges ILC presents and discuss possible management strategies to best overcome the difficulties in the loco-regional and systemic management of patients with ILC.

  7. Dynamic localization of C. elegans TPR-GoLoco proteins mediates mitotic spindle orientation by extrinsic signaling.

    Science.gov (United States)

    Werts, Adam D; Roh-Johnson, Minna; Goldstein, Bob

    2011-10-01

    Cell divisions are sometimes oriented by extrinsic signals, by mechanisms that are poorly understood. Proteins containing TPR and GoLoco-domains (C. elegans GPR-1/2, Drosophila Pins, vertebrate LGN and AGS3) are candidates for mediating mitotic spindle orientation by extrinsic signals, but the mechanisms by which TPR-GoLoco proteins may localize in response to extrinsic cues are not well defined. The C. elegans TPR-GoLoco protein pair GPR-1/2 is enriched at a site of contact between two cells - the endomesodermal precursor EMS and the germline precursor P(2) - and both cells align their divisions toward this shared cell-cell contact. To determine whether GPR-1/2 is enriched at this site within both cells, we generated mosaic embryos with GPR-1/2 bearing a different fluorescent tag in different cells. We were surprised to find that GPR-1/2 distribution is symmetric in EMS, where GPR-1/2 had been proposed to function as an asymmetric cue for spindle orientation. Instead, GPR-1/2 is asymmetrically distributed only in P(2). We demonstrate a role for normal GPR-1/2 localization in P(2) division orientation. We show that MES-1/Src signaling plays an instructive role in P(2) for asymmetric GPR-1/2 localization and normal spindle orientation. We ruled out a model in which signaling localizes GPR-1/2 by locally inhibiting LET-99, a GPR-1/2 antagonist. Instead, asymmetric GPR-1/2 distribution is established by destabilization at one cell contact, diffusion, and trapping at another cell contact. Once the mitotic spindle of P(2) is oriented normally, microtubule-dependent removal of GPR-1/2 prevented excess accumulation, in an apparent negative-feedback loop. These results highlight the role of dynamic TPR-GoLoco protein localization as a key mediator of mitotic spindle alignment in response to instructive, external cues.

  8. Simple machines

    CERN Document Server

    Graybill, George

    2007-01-01

    Just how simple are simple machines? With our ready-to-use resource, they are simple to teach and easy to learn! Chocked full of information and activities, we begin with a look at force, motion and work, and examples of simple machines in daily life are given. With this background, we move on to different kinds of simple machines including: Levers, Inclined Planes, Wedges, Screws, Pulleys, and Wheels and Axles. An exploration of some compound machines follows, such as the can opener. Our resource is a real time-saver as all the reading passages, student activities are provided. Presented in s

  9. Safety simulation technology based on finite state machine%基于有限状态机的安全性仿真技术

    Institute of Scientific and Technical Information of China (English)

    王蓓; 赵廷弟; 焦健

    2011-01-01

    为了研究系统中事故的动态变化机理,探索事故发展过程中的运动行为,制定正确的应急控制措施,提出了基于有限状态机理论的安全性建模仿真方法.结合Simulink/Stateflow工具开发了面向事故机理与应急过程的建模仿真平台,实现了系统的机理模型、安全状态控制模型以及应急操作模型的有效融合.该平台能实现对人-机-环境综合系统进行动态仿真,为明确事故的动态变化过程和制定应急控制措施提供依据.通过对某舰船舱室事故过程的仿真实例,验证了该方法的有效性和合理性.%The safety modeling and simulation method based on finite state machine theory was proposed to research the dynamic change mechanism of the accident in system, as well as explore the movement during the accident evolution and establish exact emergency treatment. The modeling and simulation platform for accident mechanism and control process was developed in the environment of Simulink/Stateflow. The combination of system mechanism model, safety state control model and emergency treatment model can be achieved in this platform. Therefore the dynamic simulation for such systems that integrated with human-machine and environment can be implemented in an effective way. Then the simulation results can be obtained, which provide reference for the precise identification of the accident process and the establishment of exact control treatment. Finally the accident simulation example was given, which proved the validity and rationality of this proposed method.

  10. Constitutive modeling for Ti-6Al-4V alloy machining based on the SHPB tests and simulation

    Science.gov (United States)

    Chen, Guang; Ke, Zhihong; Ren, Chengzu; Li, Jun

    2016-09-01

    A constitutive model is critical for the prediction accuracy of a metal cutting simulation. The highest strain rate involved in the cutting process can be in the range of 104-106 s-1. Flow stresses at high strain rates are close to that of cutting are difficult to test via experiments. Split Hopkinson compression bar (SHPB) technology is used to study the deformation behavior of Ti-6Al-4V alloy at strain rates of 10-4-104s-1. The Johnson Cook (JC) model was applied to characterize the flow stresses of the SHPB tests at various conditions. The parameters of the JC model are optimized by using a genetic algorithm technology. The JC plastic model and the energy density-based ductile failure criteria are adopted in the proposed SHPB finite element simulation model. The simulated flow stresses and the failure characteristics, such as the cracks along the adiabatic shear bands agree well with the experimental results. Afterwards, the SHPB simulation is used to simulate higher strain rate(approximately 3×104 s-1) conditions by minimizing the size of the specimen. The JC model parameters covering higher strain rate conditions which are close to the deformation condition in cutting were calculated based on the flow stresses obtained by using the SHPB tests (10-4-104 s-1) and simulation (up to 3×104 s-1). The cutting simulation using the constitutive parameters is validated by the measured forces and chip morphology. The constitutive model and parameters for high strain rate conditions that are identical to those of cutting were obtained based on the SHPB tests and simulation.

  11. Validating density-functional theory simulations at high energy-density conditions with liquid krypton shock experiments to 850 GPa on Sandia's Z machine

    Science.gov (United States)

    Mattsson, Thomas R.; Root, Seth; Mattsson, Ann E.; Shulenburger, Luke; Magyar, Rudolph J.; Flicker, Dawn G.

    2014-11-01

    We use Sandia's Z machine and magnetically accelerated flyer plates to shock compress liquid krypton to 850 GPa and compare with results from density-functional theory (DFT) based simulations using the AM05 functional. We also employ quantum Monte Carlo calculations to motivate the choice of AM05. We conclude that the DFT results are sensitive to the quality of the pseudopotential in terms of scattering properties at high energy/temperature. A new Kr projector augmented wave potential was constructed with improved scattering properties which resulted in excellent agreement with the experimental results to 850 GPa and temperatures above 10 eV (110 kK). Finally, we present comparisons of our data from the Z experiments and DFT calculations to current equation of state models of krypton to determine the best model for high energy-density applications.

  12. Feasibility study, software design, layout and simulation of a two-dimensional Fast Fourier Transform machine for use in optical array interferometry

    Science.gov (United States)

    Boriakoff, Valentin

    1994-01-01

    The goal of this project was the feasibility study of a particular architecture of a digital signal processing machine operating in real time which could do in a pipeline fashion the computation of the fast Fourier transform (FFT) of a time-domain sampled complex digital data stream. The particular architecture makes use of simple identical processors (called inner product processors) in a linear organization called a systolic array. Through computer simulation the new architecture to compute the FFT with systolic arrays was proved to be viable, and computed the FFT correctly and with the predicted particulars of operation. Integrated circuits to compute the operations expected of the vital node of the systolic architecture were proven feasible, and even with a 2 micron VLSI technology can execute the required operations in the required time. Actual construction of the integrated circuits was successful in one variant (fixed point) and unsuccessful in the other (floating point).

  13. 基于Solidworks和ADAMS的切割机虚拟样机设计与仿真分析%Virtual Prototype Design and Simulation Analysis of the Cutting Machine based on the SolidWorks and ADAMS

    Institute of Scientific and Technical Information of China (English)

    袁安富; 陆杨

    2013-01-01

    Based on the function requirements of the cutting machine, the model of the cutting machine is built by using SolidWorks software, and then it is imported into the ADAMS software. The simulation analysis of the transmission system of cutting machine is carried out and a theoretical basis for transmission system design and subsequent manufacture of cutting machine is provided.%根据切割机的功能要求,运用Solidworks软件对切割机进行建模,然后将其导入ADAMS软件中,运用ADAMS软件对其传动系统进行仿真分析,为切割机的传动系统的设计及后续的制造提供一定的理论基础.

  14. A Non-Parametric Approach for the Activation Detection of Block Design fMRI Simulated Data Using Self-Organizing Maps and Support Vector Machine.

    Science.gov (United States)

    Bahrami, Sheyda; Shamsi, Mousa

    2017-01-01

    Functional magnetic resonance imaging (fMRI) is a popular method to probe the functional organization of the brain using hemodynamic responses. In this method, volume images of the entire brain are obtained with a very good spatial resolution and low temporal resolution. However, they always suffer from high dimensionality in the face of classification algorithms. In this work, we combine a support vector machine (SVM) with a self-organizing map (SOM) for having a feature-based classification by using SVM. Then, a linear kernel SVM is used for detecting the active areas. Here, we use SOM for feature extracting and labeling the datasets. SOM has two major advances: (i) it reduces dimension of data sets for having less computational complexity and (ii) it is useful for identifying brain regions with small onset differences in hemodynamic responses. Our non-parametric model is compared with parametric and non-parametric methods. We use simulated fMRI data sets and block design inputs in this paper and consider the contrast to noise ratio (CNR) value equal to 0.6 for simulated datasets. fMRI simulated dataset has contrast 1-4% in active areas. The accuracy of our proposed method is 93.63% and the error rate is 6.37%.

  15. Electric machine

    Science.gov (United States)

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

    2012-07-17

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

  16. Loco-regional therapies for patients with hepatocellular carcinoma awaiting liver transplantation: Selecting an optimal therapy.

    Science.gov (United States)

    Byrne, Thomas J; Rakela, Jorge

    2016-06-24

    Hepatocellular carcinoma (HCC) is a common, increasingly prevalent malignancy. For all but the smallest lesions, surgical removal of cancer via resection or liver transplantation (LT) is considered the most feasible pathway to cure. Resection - even with favorable survival - is associated with a fairly high rate of recurrence, perhaps since most HCCs occur in the setting of cirrhosis. LT offers the advantage of removing not only the cancer but the diseased liver from which the cancer has arisen, and LT outperforms resection for survival with selected patients. Since time waiting for LT is time during which HCC can progress, loco-regional therapy (LRT) is widely employed by transplant centers. The purpose of LRT is either to bridge patients to LT by preventing progression and waitlist dropout, or to downstage patients who slightly exceed standard eligibility criteria initially but can fall within it after treatment. Transarterial chemoembolization and radiofrequency ablation have been the most widely utilized LRTs to date, with favorable efficacy and safety as a bridge to LT (and for the former, as a downstaging modality). The list of potentially effective LRTs has expanded in recent years, and includes transarterial chemoembolization with drug-eluting beads, radioembolization and novel forms of extracorporal therapy. Herein we appraise the various LRT modalities for HCC, and their potential roles in specific clinical scenarios in patients awaiting LT.

  17. PEDAGOGICAL TOURISM AS A TEACHING STRATEGY: EXPLORING THE IN LOCO IN THE TOURISM PROFESSIONAL TEACHING

    Directory of Open Access Journals (Sweden)

    Thais Gaia Schüler

    2016-07-01

    Full Text Available The article focuses on the discussion about the teaching experience of exploring the pedagogical tourism in the technical and professional teaching of Tourism accomplished through the case study of the Technical Course in Tourism held in the State Technical School São João Batista and decentralized classes. It was all developed based on the interpretative-idealistic paradigm, using the inductive method for discussion, having the data based on interviews, questionnaires and on the author´s praxis observation. When there was a change from the school curriculum divided in school subjects to a new curricular structure per skills, the teachers discussions pointed at the need of taking the students to field, showing the professional practice in loco and inserting a methodological strategy linked to the concept of Pedagogical Tourism. Since then, it was adopted the “technical field trips” not as an additional activity, but as part of the course teaching methodology, in order to create situations which made the student closer to the chosen professional reality. Three years after this methodology implementation, the goal is a pedagogical evaluation, pointing at advantages, disadvantages and the perceptions of students, teachers and school managers involved in the process.

  18. Cervantes en escena: El loco de la guardilla, de Narciso Serra

    Directory of Open Access Journals (Sweden)

    Menéndez Onrubia, Carmen

    2004-04-01

    Full Text Available El éxito obtenido por las tropas españolas en la Guerra de Marruecos (1859-1860 y la anexión a la corona de la isla de Santo Domingo (marzo de 1861, produjo en España un ambiente de exaltación patriótica inusitado. Sentido Cervantes por aquel entonces como el mayor representante de la lengua y de la literatura española, y crisol de la esencial nacional, recibió en 1861 sentidos homenajes populares en los escenarios madrileños. Así, se sucedieron las funciones que en reconocimiento a la peripecia vital y literaria del escritor alcalaíno se le dedicaron en el teatro del Príncipe (23-IV-1861, en el de Novedades (entre el 9 y el 23 de octubre y en la Zarzuela con el estreno del «paso» de Narciso Serra El loco de la guardilla.…

  19. Modificações texturais de tomates heterozigotos no loco alcobaça

    Directory of Open Access Journals (Sweden)

    VILAS BOAS EDUARDO VALÉRIO DE BARROS

    2000-01-01

    Full Text Available Foram avaliadas as modificações ocorridas durante o amadurecimento de três pares de híbridos de tomates do grupo multilocular, quase isogênicos, à exceção do loco alcobaça. O experimento foi conduzido na Universidade Federal de Lavras, em delineamento em blocos casualizados. Os pares de híbridos (Stevens x Flora Dade e Stevens x TOM-559; Piedmont x Flora Dade e Piedmont x TOM-559; NC-8276 x Flora Dade e NC-8276 x TOM-559 foram avaliados em quatro estádios de amadurecimento (breaker, rosa, vermelho-claro e vermelho, em quatro repetições. Os híbridos cujo genitor comum foi Flora Dade corresponderam ao genótipo normal (+/+, enquanto os híbridos heterozigotos alcobaça (+/alc foram provenientes do genitor comum TOM-559. A textura não foi afetada pelo alelo alcobaça nos estádios predeterminados de amadurecimento. Já a porcentagem de solubilização das substâncias pécticas, bem como a atividade das enzimas pectinametilesterase e poligalacturonase, foram influenciadas pelo alelo alcobaça, que determinou a sua contenção. O amadurecimento dos tomates (+/+ e (+/alc foi marcado por intenso amaciamento, acompanhado por incremento na atividade da poligalacturonase e solubilização das substâncias pécticas.

  20. Numerically Simulated Impact of Gas Prandtl Number and Flow Model on Efficiency of the Machine-less Energetic Separation Device

    Directory of Open Access Journals (Sweden)

    K. S. Egorov

    2015-01-01

    Full Text Available The presented paper regards the influence of one of similarity criteria – the Prandtl number of gas (Pr - on the efficiency of the machine-less energetic separation device (Leontiev pipe, using numerical modeling in ANSYS software. This device, equally as Rank-Hilsch and Hartman-Schprenger pipes, is designed to separate one gas flow into two flows with different temperatures. One flow (supersonic streams out of the pipe with a temperature higher than initial and the other (subsonic flows out with a temperature lower than initial. This direction of energetic separation is true if the Prandtl number is less than 1 that corresponds to gases.The Prandtl number affects the efficiency of running Leontiev pipe indirectly both through a temperature difference on which a temperature recovery factor has an impact and through a thermal conductivity coefficient that shows the impact of heat transfer intensity between gas and solid wall.The Prandtl number range in the course of research was from 0.1 to 0.7. The Prandtl number value equal to 0.7 corresponds to the air or pure gases (for example, inert argon gas. The Prandtl number equal to 0.2 corresponds to the mixtures of inert gases such as helium-xenon.The numerical modeling completed for the supersonic flow with Mach number 2.0 shows that efficiency of the machine-less energetic separation device has been increased approximately 2 times with the Prandtl number decreasing from 0.7 to 0.2. Moreover, for the counter-flow scheme this effect is a little higher due to its larger heat efficiency in comparison with the straight-flow one.Also, the research shows that the main problem for the further increase of the Leontiev pipe efficiency is a small value of thermal conductivity coefficient, which requires an intensification of the heat exchange, especially in the supersonic flow. It can be obtained, for example, by using a system of oblique shock waves in the supersonic channel.

  1. 步态训练机器人人机系统动力学仿真%Man-machine system dynamics simulation of a robot for gait training

    Institute of Scientific and Technical Information of China (English)

    张立勋; 王令军; 王凤良; 王克宽; 高峻

    2009-01-01

    Based on MATLAB the man-machine system dynamics simulation of a six-degree-of-freedom robot for gait training was completed by applying the Newton-Euler method. The kinematics constraint equations and dynamics equations of the robot were given, and the constrained matrix equation (CME) of it was constituted. Gait characteristics of people walking on the flat ground were analyzed. Combined with the pressure model of people walking on the flat ground, with the MAT-LAB toolbox, the dynamics simulation model of the man-machine system was established, and the simulation analysis of the robot' s tracking of the gait of people walking on the flat ground was carried out. The simulation results verified that the robot has good adaptability to the biped load of people, and the dynamics parameters of the robot can be conveniently acquired,so the study provides theoretical bases for achieving the robot control and performance improvement.%基于MATLAB对6自由度步态训练机器人的人机系统进行了动力学仿真研究.应用Newton-Euler法,推导了机器人的运动约束方程和动力学方程,构成了机器人的约束矩阵方程(constrained matrix equation,CME);分析了正常人在平地行走时的步态特征,并给出了人在行走时双足对地面的压力模型,利用MATLAB工具箱建立了人机系统动力学仿真模型,并对机器人跟踪人在平地行走的步态轨迹进行了仿真分析.仿真结果表明,步态训练机器人对人的双足负载具有良好的适应能力,可以方便获取机器人的动力学参数.该研究为实现机器人的控制及性能改进提供了理论依据.

  2. Simulation and Prediction of Ion Transport in the Reclamation of Sodic Soils with Gypsum Based on the Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Jinman Wang

    2014-01-01

    Full Text Available The effect of gypsum on the physical and chemical characteristics of sodic soils is nonlinear and controlled by multiple factors. The support vector machine (SVM is able to solve practical problems such as small samples, nonlinearity, high dimensions, and local minima points. This paper reports the use of the SVM regression method to predict changes in the chemical properties of sodic soils under different gypsum application rates in a soil column experiment and to evaluate the effect of gypsum reclamation on sodic soils. The research results show that (1 the SVM soil solute transport model using the Matlab toolbox represents the change in Ca2+ and Na+ in the soil solution and leachate well, with a high prediction accuracy. (2 Using the SVM model to predict the spatial and temporal variations in the soil solute content is feasible and does not require a specific mathematical model. The SVM model can take full advantage of the distribution characteristics of the training sample. (3 The workload of the soil solute transport prediction model based on the SVM is greatly reduced by not having to determine the hydrodynamic dispersion coefficient and retardation coefficient, and the model is thus highly practical.

  3. A Boltzmann machine for the organization of intelligent machines

    Science.gov (United States)

    Moed, Michael C.; Saridis, George N.

    1989-01-01

    to converge to the minimum of a cost function. Finally, simulations will show the effectiveness of a variety of search techniques for the intelligent machine.

  4. Quantum Virtual Machine (QVM)

    Energy Technology Data Exchange (ETDEWEB)

    2016-11-18

    There is a lack of state-of-the-art HPC simulation tools for simulating general quantum computing. Furthermore, there are no real software tools that integrate current quantum computers into existing classical HPC workflows. This product, the Quantum Virtual Machine (QVM), solves this problem by providing an extensible framework for pluggable virtual, or physical, quantum processing units (QPUs). It enables the execution of low level quantum assembly codes and returns the results of such executions.

  5. Using a Rapid-Kothen paper machine to simulate the effect of system closure on the contamination load of whitewater

    CSIR Research Space (South Africa)

    Naicker, Devi

    2016-01-01

    Full Text Available of the contaminants after 10 cycles exceeded standard limits for reuse of water hence treatment prior to reuse is vital in closed systems. The results demonstrate that a Rapid-Kothen sheet former can be successfully used to simulate system closure in a newsprint mill....

  6. The Machine within the Machine

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    Although Virtual Machines are widespread across CERN, you probably won't have heard of them unless you work for an experiment. Virtual machines - known as VMs - allow you to create a separate machine within your own, allowing you to run Linux on your Mac, or Windows on your Linux - whatever combination you need.   Using a CERN Virtual Machine, a Linux analysis software runs on a Macbook. When it comes to LHC data, one of the primary issues collaborations face is the diversity of computing environments among collaborators spread across the world. What if an institute cannot run the analysis software because they use different operating systems? "That's where the CernVM project comes in," says Gerardo Ganis, PH-SFT staff member and leader of the CernVM project. "We were able to respond to experimentalists' concerns by providing a virtual machine package that could be used to run experiment software. This way, no matter what hardware they have ...

  7. 小口径自动炮连发射击精度仿真%Simulation of Continuous Shoot Precision for Machine Gun of Minor-caliber

    Institute of Scientific and Technical Information of China (English)

    徐达; 韩振飞; 苏忠庭; 田佳平

    2011-01-01

    针对某小口径自动炮连发射击时射弹散布大、射击精度明显下降的问题,联合三维建模软件Pro/E,动力学仿真软件ADAMS以及有限元分析软件ANSYS,考虑身管的柔性特性,建立了小口径自动炮的刚柔耦合动力学模型。通过仿真数据与实弹射击试验数据的对比,验证了模型的可信性。在此基础上,仿真分析了该炮连发射击时的炮口动态响应规律,探究了火炮射频、复进簧刚度及炮尾质量对连发射击时炮口动态响应的影响规律。研究成果为小口径自动炮连发射击炮口动态响应规律的认识以及连发射击精度的提高提供重要的参考依据。%Aimed at the puzzle of being wide in projectile scatter and being obviously reduced in shoot precision for certain machine gun of minor-caliber in continuous shoot,the paper built the dynamics model of rigidness-flexibility coupling in machine gun of minor-caliber under the condition of combing with 3-dim modeling software Pro/E and dynamics simulation software ADAMS as well as finite element analysis software ANSYS,and considering flexibility characteristic of itself gun barrel.Through the data comparison between simulation and real shoot experiment,it verified the creditability of model.Based on that,the paper analyzed the dynamic response rule of gun muzzle when continuous shoot by simulation,and explored the muzzle response rule of shoot frequency,recoil spring rigidness and gun breech mass when continuous shoot.The research result provided important references for enhancing continuous shoot precision.

  8. Simulation of groundwater level variations using wavelet combined with neural network, linear regression and support vector machine

    Science.gov (United States)

    Ebrahimi, Hadi; Rajaee, Taher

    2017-01-01

    Simulation of groundwater level (GWL) fluctuations is an important task in management of groundwater resources. In this study, the effect of wavelet analysis on the training of the artificial neural network (ANN), multi linear regression (MLR) and support vector regression (SVR) approaches was investigated, and the ANN, MLR and SVR along with the wavelet-ANN (WNN), wavelet-MLR (WLR) and wavelet-SVR (WSVR) models were compared in simulating one-month-ahead of GWL. The only variable used to develop the models was the monthly GWL data recorded over a period of 11 years from two wells in the Qom plain, Iran. The results showed that decomposing GWL time series into several sub-time series, extremely improved the training of the models. For both wells 1 and 2, the Meyer and Db5 wavelets produced better results compared to the other wavelets; which indicated wavelet types had similar behavior in similar case studies. The optimal number of delays was 6 months, which seems to be due to natural phenomena. The best WNN model, using Meyer mother wavelet with two decomposition levels, simulated one-month-ahead with RMSE values being equal to 0.069 m and 0.154 m for wells 1 and 2, respectively. The RMSE values for the WLR model were 0.058 m and 0.111 m, and for WSVR model were 0.136 m and 0.060 m for wells 1 and 2, respectively.

  9. Evolving detectors of 2D patterns on a simulated CAM-Brain machine: an evolvable hardware tool for building a 75-million-neuron artificial brain

    Science.gov (United States)

    de Garis, Hugo; Korkin, Michael; Guttikonda, Padma; Cooley, Donald

    2000-11-01

    This paper presents some simulation results of the evolution of 2D visual pattern recognizers to be implemented very shortly on real hardware, namely the 'CAM-Brain Machine' (CBM), an FPGA based piece of evolvable hardware which implements a genetic algorithm (GA) to evolve a 3D cellular automata (CA) based neural network circuit module, of approximately 1,000 neurons, in about a second, i.e. a complete run of a GA, with 10,000s of circuit growths and performance evaluations. Up to 65,000 of these modules, each of which is evolved with a humanly specified function, can be downloaded into a large RAM space, and interconnected according to humanly specified gvdvips -o SPIE-2000.ps SPIE-2000 artificial brain architectures. This RAM, containing an artificial brain with up to 75 million neurons, is then updated by the CBM at a rate of 130 billion CA cells per second. Such speeds will enable real time control of robots and hopefully the birth of a new research field that we call 'brain building.' The first such artificial brain, to be built at STARLAB in 2000 and beyond, will be used to control the behaviors of a life sized kitten robot called 'Robokitty.' This kitten robot will need 2D pattern recognizers in the visual section of its artificial brain. This paper presents simulation results on the evolvability and generalization properties of such recognizers.

  10. Numerical simulation of the interface molten metal air in the shot sleeve chambre and mold cavity of a die casting machine

    Science.gov (United States)

    Korti, Abdel Illah Nabil; Abboudi, Said

    2011-11-01

    The objective of this study relates to the numerical simulation of the free surface during the two-dimensional flow and solidification of aluminum in the horizontal cylinder and mold cavity of the high pressure die casting HPDC machine with cold chamber. The flow is governed by the Navier-Stokes equations (the mass and the momentum conservations) and solved in the two phase's liquid aluminum and air. The tracking of the free surface is ensured by the VOF method. The equivalent specific heat method is used to solve the phase change heat transfer problem in the solidification process. Considering the displacement of the plunger, the geometry of the problem is variable and the numerical resolution uses a dynamic grid. The study examines the influence of the plunger speed on the evolution of the interface aluminum liquid-air profile, the mass of air imprisoned and the stream function contours versus time. Filling of a mold is an essential part of HPDC process and affects significantly the heat transfer and solidification of the melt. For this reason, accurate prediction of the temperature field in the system can be achieved only by including simulation of filling in the analysis.

  11. 单机变换喷射器辅助通风数值模拟%Numerical simulation analysis of ventilation of assisting single machine with ejector

    Institute of Scientific and Technical Information of China (English)

    韩建勇; 徐鹏; 张继忠

    2011-01-01

    Aimed at addressing the pollution due to harmful gas produced by blasting for roadway, this paper proposes ventilation mode of assisting single machine with ejector. This paper introduces normally forced ventilation is adopted, and changed forced ventilation to exhaust ventilation with ejector while blasting, forming hybrid ventilation mode of the ejector pressed into and the fan exhausted, and making the foul gas through ventilation duct out. The simulation of ventilation mode on 50、100 m roadway using the fluid software shows that ventilation mode of assisting single machine with ejector venting out blasting fume on 40 and 50 s respectively boasts greater benefits for long distance roadway, such as shorter discharging time and lighter polluting roadway than forced ventilation. Ventilation mode of assisting single machine with ejector , feasible for blasting roadway, provides a theoretic base for solving ventilation after blasting.%为解决爆破后产生的大量有害气体对巷道的污染问题,提出喷射器辅助单机变换通风方式.即正常情况下采用压入式通风,爆破时变压入式为抽出式并用喷射器辅助通风,形成喷射器压入、风机抽出的混合式通风方式,使污浊气体由风筒排出.利用流体软件模拟50和100m炮掘巷道通风情况,结果表明:喷射器辅助单机变换通风分别在40和50 s排出炮烟,与压入式通风相比,该方法排烟时间短,炮烟污染巷道轻,对于长距离巷道,效果更加明显.喷射器辅助单机变换通风方式对炮掘巷道是可行的.该研究为解决爆破后通风提供了理论依据.

  12. Machine Learning

    CERN Document Server

    CERN. Geneva

    2017-01-01

    Machine learning, which builds on ideas in computer science, statistics, and optimization, focuses on developing algorithms to identify patterns and regularities in data, and using these learned patterns to make predictions on new observations. Boosted by its industrial and commercial applications, the field of machine learning is quickly evolving and expanding. Recent advances have seen great success in the realms of computer vision, natural language processing, and broadly in data science. Many of these techniques have already been applied in particle physics, for instance for particle identification, detector monitoring, and the optimization of computer resources. Modern machine learning approaches, such as deep learning, are only just beginning to be applied to the analysis of High Energy Physics data to approach more and more complex problems. These classes will review the framework behind machine learning and discuss recent developments in the field.

  13. Kinematic and dynamic analysis and simulation on parallel kinematics machine tool%并联运动机床运动学和动力学分析与仿真

    Institute of Scientific and Technical Information of China (English)

    张毅; 牟思惠; 陈怀军

    2011-01-01

    以4-XPXUYYUX型并联运动机床为例,采用影响系数法建立了运动学分析的数学模型,利用Lagrange方程求解出动力学模型,为其它理论分析奠定基础。同时以虚拟样机软件ADAMS为工具,建立了并联机床的仿真模型,并对并联机床进行了动力学分析,获得了并联运动机床的动态特性,从而完善并优化了并联运动机床的系统设计。%The parallel kinematics machine tool is based on the space of mechanism.It can achieve space complex motion,meet requirements of processing of multi-degree freedom,and can process complex parts.Because the design process of a parallel kinematics machine tool is quite complicated,there are limitations of the traditional design methods using experience and static researches.It is necessary to explore the related design theories and study the dynamic characteristics of the parallel kinematics machine tool.This study takes a 4-XPXUYYUX parallel kinematics machine tool as an example,develops the mathematical model of kinematics analysis by the coefficient method.The dynamic model is solved using Lagrange equation,which can provide the basis for other theoretical analysis.We develop a simulation model of parallel kinematics machine tool by the virtual prototype software-ADAMS,and analyze the dynamic of parallel kinematics machine tool.The dynamic characteristics of parallel kinematics machine tool are acquired.The system design of parallel kinematics machine tool is improved and optimized.

  14. Accelerating Monte Carlo Molecular Simulations Using Novel Extrapolation Schemes Combined with Fast Database Generation on Massively Parallel Machines

    KAUST Repository

    Amir, Sahar Z.

    2013-05-01

    We introduce an efficient thermodynamically consistent technique to extrapolate and interpolate normalized Canonical NVT ensemble averages like pressure and energy for Lennard-Jones (L-J) fluids. Preliminary results show promising applicability in oil and gas modeling, where accurate determination of thermodynamic properties in reservoirs is challenging. The thermodynamic interpolation and thermodynamic extrapolation schemes predict ensemble averages at different thermodynamic conditions from expensively simulated data points. The methods reweight and reconstruct previously generated database values of Markov chains at neighboring temperature and density conditions. To investigate the efficiency of these methods, two databases corresponding to different combinations of normalized density and temperature are generated. One contains 175 Markov chains with 10,000,000 MC cycles each and the other contains 3000 Markov chains with 61,000,000 MC cycles each. For such massive database creation, two algorithms to parallelize the computations have been investigated. The accuracy of the thermodynamic extrapolation scheme is investigated with respect to classical interpolation and extrapolation. Finally, thermodynamic interpolation benefiting from four neighboring Markov chains points is implemented and compared with previous schemes. The thermodynamic interpolation scheme using knowledge from the four neighboring points proves to be more accurate than the thermodynamic extrapolation from the closest point only, while both thermodynamic extrapolation and thermodynamic interpolation are more accurate than the classical interpolation and extrapolation. The investigated extrapolation scheme has great potential in oil and gas reservoir modeling.That is, such a scheme has the potential to speed up the MCMC thermodynamic computation to be comparable with conventional Equation of State approaches in efficiency. In particular, this makes it applicable to large-scale optimization of L

  15. Analysis and Estimation of Values of Currents and Voltages at the Disturbances in Induction Machine Using Tested Matlab Simulation

    Directory of Open Access Journals (Sweden)

    Nenad Marković

    2014-12-01

    Full Text Available The paper we presents mathematical model for analysis of transitional processes in three-phase induction motor, that is, wave forms of currents and voltages in time domain and phase coordinates. Model is suitable for relay protection of the motor from disturbances and for estimation of electrical energy quality in the distribution network. New constructions of induction motors present more progressive technical solutions comparing with classical variants and reliable entity only within selected system of protection from expected disturbances (failures and disorders followed by asymmetries. Measuring process is not required due to application of simulation in selected MATLAB package.

  16. 无刷同步电机的起动性能仿真%Simulation of Brushless Synchronous Machine's Starting Performance

    Institute of Scientific and Technical Information of China (English)

    李岩; 张超; 刘陵顺

    2012-01-01

    For the situation that the brushless synchronous machine used to run less in starting status, this paper designs a brushless synchronous motor's simulation model in start running state. The motor starting system as the study object of the model, the use of modular thinking, were established exciter, main generator, rotating rectifier and control units and other modules, the use of these modules and build a complete start-run model, and that the model simulation studies for the early start. Simulation results show that the model has some feasibility and validity, for further study the starting performance of brushless synchronous motor lay foundation.%针对目前国内无刷同步电机较少应用于电动运行的现状,设计一种无刷同步电机起动运行状态的仿真模型.该模型以电机起动系统为研究对象,利用模块化思路,分别建立励磁机、主发电机、旋转整流器以及控制单元等模块,运用这些模块搭建一个完整的起动运行模型,并对所建立的模型进行起动初期的仿真研究.仿真结果表明:该模型有一定的可行性和有效性,能为进一步研究无刷同步电机的起动性能奠定基础.

  17. 多轴数控加工碰撞问题及其仿真研究%Multi-axis CNC machining collision and simulation research

    Institute of Scientific and Technical Information of China (English)

    赵锐; 牛兴华; 沈渤飞; 赵铁民; 王添丁

    2014-01-01

    Research on NC machining simulation and collision problem is analyzed,using the envelope of the cutting tool scanning body and fixture whether the projection of intersection as a preliminary judgment with the traditional pure tool of dis-crete vector point method for collision detection,through the simulation of real-time collision detection when the tool and fix-ture collision make corresponding parts corresponding code red tip in order to correct the wrong report. In this paper use SIEMENS NX modeling and the NC program generated with integral impeller in VERICUT simulation example shows the algo-rithm is practical and correct.%对数控加工仿真及碰撞问题进行分析研究,采用通过对刀具扫掠体包络面与夹具的投影是否相交,来作为预判断,再与传统的精判断刀具离散矢量点法相结合来进行完整的碰撞检测,并且通过仿真中的实时碰撞检测,当刀具与夹具发生碰撞时,使对应部位变成红色,相应代码提示出错误报告以便修正。本文通过SIEMENS NX建模、生成数控加工程序,以整体叶轮在VERICUT仿真中实例验证这种算法的实用性与正确性。

  18. Comparison of MRI and PET-CT in detecting the loco-regional recurrence of soft tissue sarcomas during surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun-Young [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Hallym University Sacred Heart Hospital, Department of Radiology, Anyang-si, Gyeonggi-do (Korea, Republic of); Chung, Hye Won [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Chae, Sun Young [University of Ulsan College of Medicine, Asan Medical Center, Department of Nuclear Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Lee, Jong-Seok [University of Ulsan College of Medicine, Asan Medical Center, Department of Orthopedic Surgery, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of)

    2016-10-15

    To investigate the diagnostic performance of MRI and PET-CT for the detection of loco-regional recurrences after soft tissue sarcoma (STS) excision. From Dec 2003 to Aug 2014, 394 patients with STSs, who were included in the electronic patient registry for initial or repeated surgery at our hospital, were retrospectively reviewed. We identified 152 patients who underwent regular postoperative follow-ups with both MRI and PET-CT, obtained within a 3 month period of each other. We analyzed differences in the performance of MRI and PET-CT for the diagnosis of loco-regional recurrences using McNemar's test. The receiver-operating characteristic curves and calculations of the area under the curve were used. Twenty patients were found to have a loco-regional recurrence after tumor excision. For MRI and PET-CT, the sensitivities were 90.0 and 95.0 %, and the specificities 97.7 and 95.5 %, respectively, with positive predictive values of 85.7 and 76.0 % and negative predictive values of 98.5 and 99.2 %, respectively. No significant difference was detected between the sensitivities of MRI and PET-CT (p = 0.125). The area under the receiver-operating characteristic curve for PET-CT (0.952) was not significantly greater than that for MRI (0.939; p = 0.6). MRI of the area of interest is recommended for evaluation of tumor recurrence after surgical excision of STS. PET-CT was shown to be effective for detection of STS recurrence, and comparable to MRI. However, if PET-CT or MRI findings are inconclusive, the other modality may be helpful in differentiating tumor recurrence from post-therapeutic tissue change. (orig.)

  19. Value of subtraction MRI in assessing treatment response following image-guided loco-regional therapies for hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Winters, S.D. [Department of Radiology and Diagnostic Imaging, Royal Alexandra Hospital, Edmonton (Canada); Department of Radiology and Diagnostic Imaging, University of Alberta Hospital, Edmonton (Canada); 1 Canadian Field Hospital, Department of National Defence, Government of Canada (Canada); Jackson, S. [Department of Radiology and Diagnostic Imaging, University of Alberta Hospital, Edmonton (Canada); Armstrong, G.A. [Department of Radiology and Diagnostic Imaging, Royal Alexandra Hospital, Edmonton (Canada); Department of Radiology and Diagnostic Imaging, University of Alberta Hospital, Edmonton (Canada); Birchall, I.W. [Department of Radiology and Diagnostic Imaging, University of Alberta Hospital, Edmonton (Canada); Lee, K.H.Y. [Department of Radiology and Diagnostic Imaging, Royal Alexandra Hospital, Edmonton (Canada); Low, G., E-mail: timgy@yahoo.com [Department of Radiology and Diagnostic Imaging, University of Alberta Hospital, Edmonton (Canada)

    2012-07-15

    Aim: To compare contrast-enhanced subtraction magnetic resonance imaging (MRI) with contrast-enhanced standard MRI in assessing treatment response following loco-regional therapies for hepatocellular carcinoma (HCC). Method and materials: Institutional review board approval was obtained and informed consent was waived for this retrospective study. All patients were analysed from our institution's liver tumour database that had loco-regional HCC therapy and the following: (1) a contrast-enhanced MRI {<=}6 weeks post-treatment, (2) an unenhanced T1-weighted high-signal treatment zone (TZ) {>=}1 cm, (3) follow-up contrast-enhanced MRI performed {>=}6 months post-treatment. Randomized standard and subtraction TZ datasets were independently assessed by three blinded radiology readers for either complete treatment necrosis or residual disease. The standard of reference (SOR) comprised a consensus read by two radiologists with knowledge of the follow-up MRI and all available clinical data. Statistical analyses were performed using receiver operating characteristics (ROC), t-test, and kappa statistic. Results: Twenty-six patients (19 male and seven female patients; mean age 60 years, standard deviation 10.9 years, range 46-88 years) had a total of 45 corresponding HCCs and TZs. For ROC, the area under the curve (AUC) was 0.93 (subtraction protocol) versus 0.90 (standard protocol; p = 0.49). For the t-test, the mean reader confidence level was 4.4, 3.6, and 4.4 (subtraction protocol) versus 3, 3, and 3.7 (standard protocol; p {<=} 0.011). The kappa statistic for reader-to-SOR agreement was 0.83, 0.63, and 0.71 (subtraction protocol) versus 0.51, 0.36, and 0.64 (standard protocol). Conclusion: Subtraction MRI significantly improves the reader confidence level in the assessment of treatment response following loco-regional therapies for HCC.

  20. El personaje del loco en el espectáculo medieval y en las cortes principescas del renacimiento

    Directory of Open Access Journals (Sweden)

    Francesc Massip Bonet

    2012-12-01

    Full Text Available El estudio es un paseo por las referencias literarias, archivísticas e iconográficas de fines del Medioevo e inicios del Renacimiento que documentan la actividad del personaje del loco así como del bufón cortesano en las festividades cívicas, agrarias, palaciegas o eclesiásticas, particularmente en su dimensión espectacular o dramática y en el ámbito de la Corona de Aragón.

  1. Analysis of CT-verified loco-regional recurrences after definitive IMRT for HNSCC using site of origin estimation methods

    DEFF Research Database (Denmark)

    Zukauskaite, Ruta; Hansen, Christian R; Brink, Carsten

    2017-01-01

    -regional recurrences had affirmative CT or PET/CT scan. Possible points of origin (POs) of the recurrences were identified on scans by two independent observers, estimated as center of mass and as maximum surface distance. The recurrence position was analyzed in relation to high-dose treatment volume (CTV1) and 95......% of prescription dose. RESULTS: In total, 104 loco-regional recurrences (54 in T-site and 50 in N-site) were identified in 69 patients. Median time to recurrence for the 69 patients was 10 months. No clinically relevant difference was found between the four POs, with standard deviation between POs in x, y and z...

  2. Loco-regional therapy for liver cancer%肝癌的局部区域治疗

    Institute of Scientific and Technical Information of China (English)

    叶胜龙

    2013-01-01

    局部区域治疗在影像学引导下靶向杀伤肿瘤,是原发性肝癌最主要的非手术治疗方法,包括放射介入治疗(主要为肝动脉化疗栓塞)和局部消融治疗(瘤内乙醇注射、射频、微波、激光、高强度聚焦超声、冷冻等治疗).肝动脉化疗栓塞主要应用于不能手术切除的中晚期肝癌,局部消融治疗适用于直径5 cm以下的小肝癌.肝癌局部区域治疗强调针对具体病情选择合适的方法进行规范治疗.本文简要评述各种局部区域治疗方法的指征、治疗原则、技术要点和疗效,并讨论手术切除与局部消融治疗小肝癌的选择.%Loco-regional therapy, which uses imaging technologies to facilitate targeted delivery of therapeutic agents to cancers, has emerged as the most commonly used non-surgical treatment for primary liver cancer. Since the theory of loco-regional therapy was introduced, various strategies have been developed and successfully applied in clinic, including interventional radiology methods ( mainly transarterial chemoembo-lization) and local ablative methods (such as intratumoral ethanol injection, radiofrequency ablation, microwave coagulation, laser-induced thermal therapy, high-intensity focused ultrasound, and cryotherapy). TACE has been widely applied to treat inoperable liver cancers at intermediate and advanced stages, while the local ablative therapies have proven more suitable for small ( <5 cm) liver cancers. However, choosing the appropriate loco -regional therapy strategy should be carried out on an individual basis, considering the patients particular disease condition and characteristics. To help guide such treatment decisions, this review highlights the principal indications, theory, techniques, and reported efficacies of the various loco-regional therapy strategies.

  3. Precise Nanoscale Surface Modification and Coating of Macroscale Objects: Open-Environment in Loco Atomic Layer Deposition on an Automobile.

    Science.gov (United States)

    Mousa, Moataz Bellah M; Oldham, Christopher J; Parsons, Gregory N

    2015-09-09

    The fundamental chemical reaction conditions that define atomic layer deposition (ALD) can be achieved in an open environment on a macroscale surface too large and complex for typical laboratory reactor-based ALD. We describe the concept of in loco ALD using conventional modulated reactant flow through a surface-mounted "ALD delivery head" to form a precise nanoscale Al2O3 film on the window of a parked automobile. Analysis confirms that the processes eliminated ambient water contamination and met other conditions that define ALD growth. Using this tool, we demonstrate open-ambient patterned deposition, metal corrosion protection, and polymer surface modification.

  4. 基于VERICUT 的双主轴龙门加工中心数控加工仿真技术应用%The Dual Spindles Gantry CNC Machining Simulation Technology based on VERICUT

    Institute of Scientific and Technical Information of China (English)

    宋福田; 王忠平; 王泰吉

    2016-01-01

    CNC machining simulation is mapped in a virtual environment that provides crucial data for product manufac-ture analysis.VERICUT simulation solution can simulate the whole manufacturing process,including the NC program veri-fication which can reduce the actual risk of the first part testing cut,and collision check for potential errors.A dual spindle gantry CNC machine center building,based on analyzing the machine structure and special commands,is combined with VERICUT machine component tree creation,control system configuration,tooling creation and work offset setting.The keys of this research are configurations and development of this machine special synchronization commands and mirroring machining function,tooling and special work offsets setting.Summarize the dual spindles gantry CNC machine center simu-lation configurations in VERICUT simulation solution.%数控仿真是数控加工在虚拟环境中的映射,它为产品的可制造性分析提供关键数据。通过基于 VERICUT 软件的虚拟制造软件平台,可以仿真零件数控加工的完整制造过程,包括验证数控程序的正确性,减少零件首件调试风险以及模拟数控机床的实际运动,检查潜在的碰撞错误,降低碰撞的风险。双主轴龙门加工中心的虚拟制造软件平台的创建是通过分析机床结构和特殊指令,并结合 VERI-CUT 软件进行机床结构树的构建、数控系统的配置、刀具的创建和加工零点的设置等主要切削仿真环境构建内容。重点研究了机床上同步和镜像加工特殊指令的配置及开发,以及刀具创建、特殊加工坐标系原点的创建,总结了双主轴龙门加工中心这类机床在 VERICUT 软件中构建仿真环境的方法。

  5. Polishing tool and the resulting TIF for three variable machine parameters as input for the removal simulation

    Science.gov (United States)

    Schneider, Robert; Haberl, Alexander; Rascher, Rolf

    2017-06-01

    The trend in the optic industry shows, that it is increasingly important to be able to manufacture complex lens geometries on a high level of precision. From a certain limit on the required shape accuracy of optical workpieces, the processing is changed from the two-dimensional to point-shaped processing. It is very important that the process is as stable as possible during the in point-shaped processing. To ensure stability, usually only one process parameter is varied during processing. It is common that this parameter is the feed rate, which corresponds to the dwell time. In the research project ArenA-FOi (Application-oriented analysis of resource-saving and energy-efficient design of industrial facilities for the optical industry), a touching procedure is used in the point-attack, and in this case a close look is made as to whether a change of several process parameters is meaningful during a processing. The ADAPT tool in size R20 from Satisloh AG is used, which is also available for purchase. The behavior of the tool is tested under constant conditions in the MCP 250 CNC by OptoTech GmbH. A series of experiments should enable the TIF (tool influence function) to be determined using three variable parameters. Furthermore, the maximum error frequency that can be processed is calculated as an example for one parameter set and serves as an outlook for further investigations. The test results serve as the basic for the later removal simulation, which must be able to deal with a variable TIF. This topic has already been successfully implemented in another research project of the Institute for Precision Manufacturing and High-Frequency Technology (IPH) and thus this algorithm can be used. The next step is the useful implementation of the collected knowledge. The TIF must be selected on the basis of the measured data. It is important to know the error frequencies to select the optimal TIF. Thus, it is possible to compare the simulated results with real measurement

  6. Machine Learning

    Energy Technology Data Exchange (ETDEWEB)

    Chikkagoudar, Satish; Chatterjee, Samrat; Thomas, Dennis G.; Carroll, Thomas E.; Muller, George

    2017-04-21

    The absence of a robust and unified theory of cyber dynamics presents challenges and opportunities for using machine learning based data-driven approaches to further the understanding of the behavior of such complex systems. Analysts can also use machine learning approaches to gain operational insights. In order to be operationally beneficial, cybersecurity machine learning based models need to have the ability to: (1) represent a real-world system, (2) infer system properties, and (3) learn and adapt based on expert knowledge and observations. Probabilistic models and Probabilistic graphical models provide these necessary properties and are further explored in this chapter. Bayesian Networks and Hidden Markov Models are introduced as an example of a widely used data driven classification/modeling strategy.

  7. Design and Simulation of New Cascade Brushless Doubly-fed Machine%新型级联式无刷双馈电机设计与仿真

    Institute of Scientific and Technical Information of China (English)

    徐优; 王自强

    2015-01-01

    The new cascade Brushless Doubly-fed Machine ( BDFM) is mainly used for wind power , when the speed of prime mover changes , without changing the input frequency of the excitation current , this generator can guarantee the frequency of the output current is constant , which realize the variable speed constant frequency (VSCF) power.The working principle of the new cascade BDFM was derived , and two motors were established in Ansoft software , then imported into Simplorer software , cascaded and simulated . Simulation results show that if the new cascade BDFM make sure two coaxial rotorsare connected with the same phase sequence and two motor pole pairs are equal , it can achieve VSCF power without inv erter.%新型级联式无刷双馈发电机可以看作是普通级联式双馈电机的一种特例,主要用于风力发电,当电机转速变化时,不需要改变输入励磁电压的频率就可以保证电机输出的电压频率恒定,方便的实现了变速恒频发电。对新型级联式双馈电机的工作原理进行了简要论述,在Ansoft软件里面建立了电机的模型,并导入到Simplorer软件,把两个电机级联起来进行了仿真。仿真结果表明新型级联式双馈电机只需确保两电机转子同轴同相序连接,且两电机极对数相等,即可实现无需变频器的变速恒频发电。

  8. Simulated Microgravity Regulates Gene Transcript Profiles of 2T3 Preosteoblasts: Comparison of the Random Positioning Machine and the Rotating Wall Vessel Bioreactor

    Science.gov (United States)

    Patel, Mamta J.; Liu, Wenbin; Sykes, Michelle C.; Ward, Nancy E.; Risin, Semyon A.; Risin, Diana; Hanjoong, Jo

    2007-01-01

    Microgravity of spaceflight induces bone loss due in part to decreased bone formation by osteoblasts. We have previously examined the microgravity-induced changes in gene expression profiles in 2T3 preosteoblasts using the Random Positioning Machine (RPM) to simulate microgravity conditions. Here, we hypothesized that exposure of preosteoblasts to an independent microgravity simulator, the Rotating Wall Vessel (RWV), induces similar changes in differentiation and gene transcript profiles, resulting in a more confined list of gravi-sensitive genes that may play a role in bone formation. In comparison to static 1g controls, exposure of 2T3 cells to RWV for 3 days inhibited alkaline phosphatase activity, a marker of differentiation, and downregulated 61 genes and upregulated 45 genes by more than two-fold as shown by microarray analysis. The microarray results were confirmed with real time PCR for downregulated genes osteomodulin, bone morphogenic protein 4 (BMP4), runx2, and parathyroid hormone receptor 1. Western blot analysis validated the expression of three downregulated genes, BMP4, peroxiredoxin IV, and osteoglycin, and one upregulated gene peroxiredoxin I. Comparison of the microarrays from the RPM and the RWV studies identified 14 gravi-sensitive genes that changed in the same direction in both systems. Further comparison of our results to a published database showing gene transcript profiles of mechanically loaded mouse tibiae revealed 16 genes upregulated by the loading that were shown to be downregulated by RWV and RPM. These mechanosensitive genes identified by the comparative studies may provide novel insights into understanding the mechanisms regulating bone formation and potential targets of countermeasure against decreased bone formation both in astronauts and in general patients with musculoskeletal disorders.

  9. Digital Prototype of Energy-saving Oil Pumping Machine and Numerical Simulation Analysis of Its Key Component%抽油机数字样机建立与关键部件数值仿真分析

    Institute of Scientific and Technical Information of China (English)

    王小明; 朱颖; 袁亮; 吴强; 李智钟

    2013-01-01

    The paper presents how to utilize the virtual prototype technology to build and analyze the beam oil pumping machine whose diameter and torgque can be adjusted .First of all ,the 3D solid models of the parts in oil pumping machine are built . Secondly ,the whole machine is assembled in UG .Finally ,the key component of the oil pumping machine is analyzed using the numerical simulation approach in ANSYS (this paper only analyzes the head of the oil pumping machine) .Some basic data including the stress ,strain and stress concentration of the key part are achieved using this approach ,which will provide a basis for the structure optimizatin design of the key component .%采用虚拟样机技术,以游梁式调径变矩抽油机为研究对象,首先建立抽油机的三维实体零件模型,其次在UG环境下完成整体的装配,并在 ANSYS的工作环境下对抽油机关键部件(驴头)进行数值仿真分析,得到关键部件的应力、应变以及应力集中等基本数据,为关键部件的结构优化设计提供依据。

  10. Modeling and Simulation of Five-axis NC Rotary Table Virtual Prototype Machine%工作台回转式五轴数控机床虚拟样机建模与数控仿真

    Institute of Scientific and Technical Information of China (English)

    姜雨; 李立军; 丁明

    2012-01-01

    Taking five-axis machine tool with rotary table as the research subject, through the CAD module of UG, the STL models of machine tool and the parts to be machined were built. Then they were transfered into VERICUT to complete the virtual model of the machine tool. Making a series of setting for the established virtual model, the NC programs were called to complete the modeling and simulation of five-axis NC rotary table virtual prototype machine.%以工作台回转式五轴数控机床为研究对象,通过UG的CAD模块建立该机床和被加工件的虚拟模型并输出各组件的STL模型,再导人VERICUT中,完成机床在VERICUT中的虚拟建模.对建立好的虚拟模型进行设置,调用数控程序完成工作台回转式五轴数控虚拟样机的建模和仿真.

  11. LoCo: a novel main chain scoring function for protein structure prediction based on local coordinates

    Directory of Open Access Journals (Sweden)

    Samudrala Ram

    2011-09-01

    Full Text Available Abstract Background Successful protein structure prediction requires accurate low-resolution scoring functions so that protein main chain conformations that are close to the native can be identified. Once that is accomplished, a more detailed and time-consuming treatment to produce all-atom models can be undertaken. The earliest low-resolution scoring used simple distance-based "contact potentials," but more recently, the relative orientations of interacting amino acids have been taken into account to improve performance. Results We developed a new knowledge-based scoring function, LoCo, that locates the interaction partners of each individual residue within a local coordinate system based only on the position of its main chain N, Cα and C atoms. LoCo was trained on a large set of experimentally determined structures and optimized using standard sets of modeled structures, or "decoys." No structure used to train or optimize the function was included among those used to test it. When tested against 29 other published main chain functions on a group of 77 commonly used decoy sets, our function outperformed all others in Cα RMSD rank of the best-scoring decoy, with statistically significant p-values Conclusions Our function demonstrates an unmatched combination of accuracy, speed, and simplicity and shows excellent promise for protein structure prediction. Broader applications may include protein-protein interactions and protein design.

  12. Machine testning

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This document is used in connection with a laboratory exercise of 3 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercise includes a series of tests carried out by the student on a conventional and a numerically controled lathe, respectively. This document...

  13. Representational Machines

    DEFF Research Database (Denmark)

    Petersson, Dag; Dahlgren, Anna; Vestberg, Nina Lager

    to the enterprises of the medium. This is the subject of Representational Machines: How photography enlists the workings of institutional technologies in search of establishing new iconic and social spaces. Together, the contributions to this edited volume span historical epochs, social environments, technological...

  14. Endarterectomia carotídea sob bloqueio loco-regional Carotid endarterectomy under locoregional anesthesia

    Directory of Open Access Journals (Sweden)

    Ana Terezinha Guillaumon

    2005-09-01

    Full Text Available OBJETIVO: Os autores objetivam descrever os resultados nas cirurgias de endarterectomia carotídea, utilizando-se anestesia loco-regional, emprego seletivo de shunt e proteção farmacológica intra-operatória. MÉTODO: Foram estudados doentes submetidos à endarterectomia carotídea sob bloqueio loco-regional, no Hospital das Clínicas da Universidade Estadual de Campinas (UNICAMP, no período de março de 1996 a maio de 2004. Este estudo é composto de 119 endarterectomias (108 doentes, sendo 69 doentes (63,8% do sexo masculino e 39 (36,2% do sexo feminino. A idade média foi de 63 anos, variando entre 43 e 83 anos. A indicação da operação foi estenose sintomática em 60 doentes (55,5% e assintomática em 48 (44,5%. Foi realizada avaliação, por imagem, pelo eco-Doppler colorido e arteriografia. RESULTADOS: Foram excluídos do trabalho cinco doentes nos quais foi necessária a conversão para a anestesia geral por intolerância à colocação do clampe carotídeo. Dos 103 doentes submetidos a 114 endarterectomias, utilizamos um shunt em quatro cirurgias (3,5%, em função da intolerância do paciente à colocação do clampe carotídeo durante o ato cirúrgico. Utilizou-se remendo em 19 (16,6% cirurgias. A mortalidade no período pós-operatório imediato ocorreu em três doentes (2,6%, todos em decorrência de acidente vascular cerebral. Um doente (0,87% apresentou acidente vascular isquêmico menor, e um (0,87% doente apresentou síndrome de hiperperfusão, que evoluiu com acidente vascular cerebral hemorrágico. Esse doente foi submetido à drenagem do hematoma cerebral, com recuperação total do déficit neurológico. No pós-operatório tardio, houve reestenose ou oclusão em quatro doentes (5,3%. CONCLUSÃO: A endarterectomia carotídea pode ser realizada com segurança no doente em vigília, utilizando-se o shunt seletivamente, com a utilização de fármaco-proteção cerebral. O bom resultado obtido e a baixa morbimortalidade

  15. Pulmonary function after high-dose chemotherapy with autologous bone marrow transplantation and radiotherapy in patients with advanced loco-regional breast cancer

    NARCIS (Netherlands)

    Dolsma, WV; DeVries, EGE; VanderMark, TW; Sleijfer, DT; Willemse, PHB; VanderGraaf, WTA; Mulder, POM; Szabo, BG; Mulder, NH

    1997-01-01

    Our aim was to study the extent of pulmonary toxicity after high-dose chemotherapy and radiotherapy in breast cancer patients. In a retrospective study the pulmonary symptoms and chest X-rays were analysed before, during and after treatment in 17 patients, treated with loco-regional radiotherapy to

  16. Reconceptualizing the University's Duty to Provide a Safe Learning Environment: A Criticism of the Doctrine of "In Loco Parentis" and the Restatement (Second) of Torts.

    Science.gov (United States)

    Bickel, Robert D.; Lake, Peter F.

    1994-01-01

    Litigation concerning the responsibility of a college or university to provide a safe environment for students is reviewed, focusing on interpretations of the "in loco parentis" doctrine. It is argued that institutions have a duty to not only provide campus security but also enforce a code of civility on campus. (MSE)

  17. In Loco Parentis: Recent Developments in this Legal Doctrine as Applied to the University-Student Relationship in the United States of America, 1965-75.

    Science.gov (United States)

    Conrath, Richard Cranmer

    Is the doctrine of "in loco parentis" a viable legal theory today for describing the relationship between the university and the student in the United States? The student dissent of the 1960's forced both the universities and the courts to reconsider the basic legal nature of the university-student relationship, but there is still…

  18. A pilot study to investigate the role of the 26S proteasome in radiotherapy resistance and loco-regional recurrence following breast conserving therapy for early breast cancer.

    Science.gov (United States)

    Elfadl, Dalia; Hodgkinson, Victoria C; Long, Ervine D; Scaife, Lucy; Drew, Philip J; Lind, Michael J; Cawkwell, Lynn

    2011-08-01

    Breast conserving therapy is a currently accepted method for managing patients with early stage breast cancer. However, approximately 7% of patients may develop loco-regional tumour recurrence within 5 years. We previously reported that expression of the 26S proteasome may be associated with radio-resistance. Here we aimed to analyse the 26S proteasome in a pilot series of early breast cancers and correlate the findings with loco-regional recurrence. Fourteen patients with early breast cancer who developed loco-regional recurrence within 4 years of completing breast conserving therapy were selected according to strict criteria and compared with those from 14 patients who were disease-free at 10 years. Decreased expression of the 26S proteasome was significantly associated with radio-resistance, manifested as the development of a loco-regional recurrence within 4 years of breast conserving therapy (p = 0.018). This small pilot study provides further suggestion that the 26S proteasome may be associated with response to radiotherapy.

  19. Adding machine and calculating machine

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In 1642 the French mathematician Blaise Pascal(1623-1662) invented a machine;.that could add and subtract. It had.wheels that each had: 1 to 10 marked off along its circumference. When the wheel at the right, representing units, made one complete circle, it engaged the wheel to its left, represents tens, and moved it forward one notch.

  20. Genesis machines

    CERN Document Server

    Amos, Martyn

    2014-01-01

    Silicon chips are out. Today's scientists are using real, wet, squishy, living biology to build the next generation of computers. Cells, gels and DNA strands are the 'wetware' of the twenty-first century. Much smaller and more intelligent, these organic computers open up revolutionary possibilities. Tracing the history of computing and revealing a brave new world to come, Genesis Machines describes how this new technology will change the way we think not just about computers - but about life itself.

  1. Static simulation on rolling impact compaction machines%滚动冲击压实机静态仿真分析

    Institute of Scientific and Technical Information of China (English)

    宋智; 高有山; 王爱红; 靳泽昆

    2012-01-01

    通过仿真研究滚动冲击压实机变矩器的无因次特性、发动机变矩器的共同输入输出特性和牵引车的牵引特性.仿真结果表明:发动机转矩特性曲线和变矩器输入扭矩曲线的交点是发动机与变矩器共同工作的稳定点,其工作范围是变矩器输入扭矩曲线与发动机外特性曲线所围成的最大区域;1挡、2挡、倒挡最高车速分别为11.054,35.44,14.812km· h-1;最大有效牵引功率为54 kW;最大牵引效率为53%;额定滑转率为29%;变矩器最大输出功率对应的牵引力为61 kN;附着条件决定的最大牵引力为83kN.%Such properties as the dimensionless, common input and output between engine and torque converter, and traction of tractor are simulated on rolling impact compaction machines. From the simulation results, it is indicated that the intersect between torque property curve of engine and input torque curve of torque converter is a common stable working point, whereas the working scope is the maximum covering area of both curves. In addition, the maximum speeds of the first, the second and the reverse gears are 11.054, 35.44,14.812 km·h-1, respectively. In this case, the maximum effective traction power is 54 kW, the maximum traction efficiency is 53%, the rated slip-ratio is 29%, the traction force regarding the maximum output power of torque converter is 61 kN, the maximum traction force subject to additional conditions is 83 kN.

  2. 基于UG内啮合珩齿的仿真加工分析%Simulation Machining Analysis for Internal Gear Honing based on UG

    Institute of Scientific and Technical Information of China (English)

    师瑜; 赵洪鹤; 张满栋

    2013-01-01

    Internal gear honing is a process of precise machining of the gear, in the process, there exists trace amounts of interference between tooth surfaces as helical internal honing wheel and spur gear are a gear pair with crossed shaft, a crown teeth can be obtained by removing the interference amount, and the crown teeth brings great benefit for reducing noise and enhancing the stability of transmission of the gear. Because the meshing of a crossed shaft gear pair is very complex, the analytical calculation of the quantity of interference between teeth is also difficult to be achieved. By using a 3 - D modeling software UG/NX, the parameter of the cylindrical internal helical gear and the spur gear modeling and assembly simulation is realized, through the simulation of gear meshing movement, interference is successfully removed to process the crown teeth, and finally data of interference for a single tooth is obtained.%内啮合珩齿是一种齿轮精密加工的工艺方法,由于其斜齿内珩轮与直齿圆柱齿轮属于交错轴齿轮副,齿面之间存在着微量的干涉.通过去除干涉量可得到鼓形齿,而鼓形齿对于降低噪声,增强齿轮传动的平稳性都有极大的益处.由于交错轴齿轮副的啮合情况非常复杂,轮齿之间的干涉量解析计算也难以实现.为此利用三维建模软件UG/NX实现了对圆柱内斜齿轮和直齿圆柱齿轮参数建模和装配,通过模拟齿轮的啮合运动,成功将干涉部分切除加工出鼓形齿.最终得到单个齿上的干涉量.

  3. Prognostic impact of epidermal growth factor receptor (EGFR expression on loco-regional recurrence after preoperative radiotherapy in rectal cancer

    Directory of Open Access Journals (Sweden)

    Ychou Marc

    2005-06-01

    Full Text Available Abstract Background Epidermal growth factor receptor (EGFR represents a major target for current radiosensitizing strategies. We wished to ascertain whether a correlation exists between the expression of EGFR and treatment outcome in a group of patients with rectal adenocarcinoma who had undergone preoperative radiotherapy (RT. Methods Within a six-year period, 138 patients underwent preoperative radiotherapy and curative surgery for rectal cancer (UICC stages II-III at our institute. Among them, 77 pretherapeutic tumor biopsies were available for semi-quantitative immunohistochemical investigation evaluating the intensity and the number (extent of tumor stained cells. Statistical analyses included Cox regression for calculating risk ratios of survival endpoints and logistic regression for determining odds ratios for the development of loco-regional recurrences. Results Median age was 64 years (range: 30–88. Initial staging showed 75% and 25% stage II and III tumors, respectively. RT consisted of 44-Gy pelvic irradiation in 2-Gy fractions using 18-MV photons. In 25 very low-rectal-cancer patients the primary tumor received a boost dose of up to 16 Gy for a sphincter-preservation approach. Concomitant chemotherapy was used in 17% of the cases. All patients underwent complete total mesorectal resection. Positive staining (EGFR+ was observed in 43 patients (56%. Median follow-up was 36 months (range: 6–86. Locoregional recurrence rates were 7 and 20% for EGFR extent inferior and superior to 25%, respectively. The corresponding locoregional recurrence-free survival rate at two years was 94% (95% confidence interval, CI, 92–98% and 84% (CI 95%, 58–95%, respectively (P = 0.06. Multivariate analyses showed a significant correlation between the rate of loco-regional recurrence and three parameters: EGFR extent superior to 25% (hazard ratio = 7.18, CI 95%, 1.17–46, P = 0.037, rectal resection with microscopic residue (hazard ratio = 6.92, CI 95

  4. Visual Simulation System of Operation Trajectory for Arm-type Placement Machine%动臂式贴片机贴装轨迹的可视化仿真

    Institute of Scientific and Technical Information of China (English)

    钱佳敏; 于兰峰; 曹晔; 朱小龙; 郭俊才

    2012-01-01

    贴片机是电子制造业中最重要的生产设备,针对贴片机试贴过程资源浪费大、成本高、效率低的问题,开发了一种模拟贴片机贴装轨迹的可视化仿真系统.在分析研究贴片机结构与贴装工艺流程的基础上,结合使用外部模型导入与OpenGL绘图两种方式,构造了复杂的贴片机模型以及参数化原件模型库,并在用VC++开发的人机界面下由数据库提供贴装参数,OpenGL函数显示控制模型运动,实现了贴片机贴装过程在计算机虚拟环境下的可视化仿真,从而提高了贴片机程序的可视化程度,降低试贴成本.%Placement machine Li the foremost equipment in electronic manufacturing. For the wasting of resources ,high cost and lotv efficiency in the paste test of the placement machine,α visual simulation system was developed to solve the problem.Based on analyzing the structure of the machine and the placement process .combined with importing of external model and OpenGL draw, α complex model of placement machine and model library for parametric original was createdIn addition the placement parameters was provided by database under man-machine interface developed by the VC++ software,then the OpenGL function was applied to indicate and control the motion of the model,which realized the visual simulation of the placement process of the machine under the computer virtual environment,thus the visualization of the machine program was improved and the cost of paste test was reduced.

  5. 预应力硬态切削加工中残余应力的数值模拟%Simulation of Residual Stress States in Pre-stress Hard Machining

    Institute of Scientific and Technical Information of China (English)

    彭锐涛; 叶邦彦; 唐新姿; 尹美

    2007-01-01

    航空轴承外圈的疲劳裂纹分析表明,套圈表面的残余压应力分布致使轴承表面接触疲劳寿命降低.预应力切削是一种能主动控制加工表面的残余应力状态的方法,它是通过预先给工件施加一个弹性范围内的张应力后再进行切削加工.针对预应力硬态切削的特点,建立了切削模拟的三维热力耦合模型;分析研究了材料本构方程、任意拉格朗日-欧拉方法以及刀屑接触面的摩擦模型等切削模拟中的关键技术.最后,通过切削实验和有限元模拟,比较和分析了预应力硬态切削对加工表面应力状态的影响,证明了预应力切削方法能在加工表面产生残余压应力,从而提高加工表面的接触疲劳寿命.%The analysis on fatigue cracks of the outer race of aero-bearing shows that the distribution of residual tensile stress on race surface could reduce its contact fatigue life. The method of pre-stress hard machining, which is a process that imposes a tensile stress to work piece within elastic limit beforehand and then exerts machining,can actively control the residual stress states of machined surface. Based on the characteristics of pre-stress hard machining, a 3D coupled thermo-mechanical model is constructed. Several key numerical techniques, such as the constitutive equation of material, the Arbitrary Lagrangian Eulerian (ALE) method and the friction law along the chip-tool interface have been analyzed and implemented. In the end, through combining cutting experiments and numerical simulations, the residual stress states of machined surface in pre-stress hard machining are compared and analyzed. Simulation and experiment results indicate that this method can acquire residual compressive stress on machined surface and prolong the contact fatigue life.

  6. Environmentally Friendly Machining

    CERN Document Server

    Dixit, U S; Davim, J Paulo

    2012-01-01

    Environment-Friendly Machining provides an in-depth overview of environmentally-friendly machining processes, covering numerous different types of machining in order to identify which practice is the most environmentally sustainable. The book discusses three systems at length: machining with minimal cutting fluid, air-cooled machining and dry machining. Also covered is a way to conserve energy during machining processes, along with useful data and detailed descriptions for developing and utilizing the most efficient modern machining tools. Researchers and engineers looking for sustainable machining solutions will find Environment-Friendly Machining to be a useful volume.

  7. Engineering molecular machines

    Science.gov (United States)

    Erman, Burak

    2016-04-01

    Biological molecular motors use chemical energy, mostly in the form of ATP hydrolysis, and convert it to mechanical energy. Correlated thermal fluctuations are essential for the function of a molecular machine and it is the hydrolysis of ATP that modifies the correlated fluctuations of the system. Correlations are consequences of the molecular architecture of the protein. The idea that synthetic molecular machines may be constructed by designing the proper molecular architecture is challenging. In their paper, Sarkar et al (2016 New J. Phys. 18 043006) propose a synthetic molecular motor based on the coarse grained elastic network model of proteins and show by numerical simulations that motor function is realized, ranging from deterministic to thermal, depending on temperature. This work opens up a new range of possibilities of molecular architecture based engine design.

  8. Ocean Acidification Disrupts Prey Responses to Predator Cues but Not Net Prey Shell Growth in Concholepas concholepas (loco)

    Science.gov (United States)

    Manríquez, Patricio H.; Jara, María Elisa; Mardones, María Loreto; Navarro, Jorge M.; Torres, Rodrigo; Lardies, Marcos A.; Vargas, Cristian A.; Duarte, Cristian; Widdicombe, Stephen; Salisbury, Joseph; Lagos, Nelson A.

    2013-01-01

    Background Most research on Ocean Acidification (OA) has largely focused on the process of calcification and the physiological trade-offs employed by calcifying organisms to support the building of calcium carbonate structures. However, there is growing evidence that OA can also impact upon other key biological processes such as survival, growth and behaviour. On wave-swept rocky shores the ability of gastropods to self-right after dislodgement, and rapidly return to normal orientation, reduces the risk of predation. Methodology/Principal Findings The impacts of OA on this self-righting behaviour and other important parameters such as growth, survival, shell dissolution and shell deposition in Concholepas concholepas (loco) were investigated under contrasting pCO2 levels. Although no impacts of OA on either growth or net shell calcification were found, the results did show that OA can significantly affect self-righting behaviour during the early ontogeny of this species with significantly faster righting times recorded for individuals of C. concholepas reared under increased average pCO2 concentrations (± SE) (716±12 and 1036±14 µatm CO2) compared to those reared at concentrations equivalent to those presently found in the surface ocean (388±8 µatm CO2). When loco were also exposed to the predatory crab Acanthocyclus hassleri, righting times were again increased by exposure to elevated CO2, although self-righting times were generally twice as fast as those observed in the absence of the crab. Conclusions and Significance These results suggest that self-righting in the early ontogeny of C. concholepas will be positively affected by pCO2 levels expected by the end of the 21st century and beginning of the next one. However, as the rate of self-righting is an adaptive trait evolved to reduce lethal predatory attacks, our result also suggest that OA may disrupt prey responses to predators in nature. PMID:23844231

  9. Regional PET/CT after water gastric inflation for evaluating loco-regional disease of gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soo Jin, E-mail: suji76@hanmail.net [Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine (Korea, Republic of); Lee, Won Woo, E-mail: wwlee@snubh.org [Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine (Korea, Republic of); Institute of Radiation Medicine, Medical Research Center, Seoul National University (Korea, Republic of); Yoon, Hai-Jeon, E-mail: punsu07@naver.com [Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine (Korea, Republic of); Lee, Ho-Young, E-mail: debobkr@gmail.com [Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine (Korea, Republic of); Lee, Kyoung Ho, E-mail: kholeemail@gmail.com [Department of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine (Korea, Republic of); Institute of Radiation Medicine, Medical Research Center, Seoul National University (Korea, Republic of); Kim, Young Hoon, E-mail: yhkrad@gmail.com [Department of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine (Korea, Republic of); Institute of Radiation Medicine, Medical Research Center, Seoul National University (Korea, Republic of); Park, Do Joong, E-mail: djpark@snubh.org [Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine (Korea, Republic of); Kim, Hyung-Ho, E-mail: hhkim@snubh.org [Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine (Korea, Republic of); So, Young, E-mail: youngso@kuh.ac.kr [Department of Nuclear Medicine, Konkuk University School of Medicine (Korea, Republic of); and others

    2013-06-15

    Objective: We aimed to improve diagnostic accuracy of {sup 18}F-fluoro-2-deoxyglucose (FDG) PET/CT for gastric cancer with water gastric inflation. Materials and methods: 44 gastric cancer patients (M:F = 30:14, age ± std = 62.1 ± 14.5y) were enrolled before surgery. Fifty minutes after injection of FDG (0.14 mCi/kg body weight), whole body PET/CT was performed first and then regional PET/CT over gastric area was obtained 80 min post FDG injection after water gastric inflation. Diagnostic accuracies for loco-regional lesions were compared between whole body and regional PET/CT. Results: 48 primary tumors (23 EGC and 25 AGC) and 348 LN stations (61 metastatic and 287 benign) in 44 patients were investigated. Primary tumor sensitivity of whole body PET/CT (50% = 24/48) was significantly improved by regional PET/CT (75% = 36/48, p < 0.005). Sensitivity of whole body PET/CT (24.6% = 15/61) for LN metastasis was also significantly improved by regional PET/CT (36.1% = 22/61, p < 0.01), whereas specificity of whole body PET/CT (99.3% = 285/287) was not compromised by regional PET/CT (98.3% = 282/287, p > 0.05). Higher primary tumor FDG uptake in regional PET/CT indicated shorter progress-free survival (p = 0.0003). Conclusion: Diagnostic accuracy of whole body PET/CT for loco-regional disease of gastric cancer could be significantly improved by regional PET/CT after water gastric inflation and prognosis could be effectively predicted by primary tumor FDG uptake in regional PET/CT.

  10. Abstract quantum computing machines and quantum computational logics

    Science.gov (United States)

    Chiara, Maria Luisa Dalla; Giuntini, Roberto; Sergioli, Giuseppe; Leporini, Roberto

    2016-06-01

    Classical and quantum parallelism are deeply different, although it is sometimes claimed that quantum Turing machines are nothing but special examples of classical probabilistic machines. We introduce the concepts of deterministic state machine, classical probabilistic state machine and quantum state machine. On this basis, we discuss the question: To what extent can quantum state machines be simulated by classical probabilistic state machines? Each state machine is devoted to a single task determined by its program. Real computers, however, behave differently, being able to solve different kinds of problems. This capacity can be modeled, in the quantum case, by the mathematical notion of abstract quantum computing machine, whose different programs determine different quantum state machines. The computations of abstract quantum computing machines can be linguistically described by the formulas of a particular form of quantum logic, termed quantum computational logic.

  11. Machine Transliteration

    CERN Document Server

    Knight, K; Knight, Kevin; Graehl, Jonathan

    1997-01-01

    It is challenging to translate names and technical terms across languages with different alphabets and sound inventories. These items are commonly transliterated, i.e., replaced with approximate phonetic equivalents. For example, "computer" in English comes out as "konpyuutaa" in Japanese. Translating such items from Japanese back to English is even more challenging, and of practical interest, as transliterated items make up the bulk of text phrases not found in bilingual dictionaries. We describe and evaluate a method for performing backwards transliterations by machine. This method uses a generative model, incorporating several distinct stages in the transliteration process.

  12. 溴化锂吸收式制冷机模拟实验教学系统设计%Design of simulating experimental teaching system for LiBr absorption-type refrigerating machines

    Institute of Scientific and Technical Information of China (English)

    王美霞; 邵莉; 韩吉田

    2011-01-01

    A simulation experimental system for absorption-type refrigerating machines was designed based on the ACAD and Visual Basic software. The use of the system can not only complete structure model of absorption-type refrigerating machine and thermal calculation for the absorption-type refrigerating cycle, but also simulate the PID control system and realize intelligent controls. The experimental system has the friendly man-machine interface beneficial to the students' operating and understanding, thereby decreasing the students' difficulties in learning and improving the experiment teaching effect.%利用ACAD和Visual Basic软件对溴化锂吸收式制冷机组进行实验教学仿真系统设计,可以完成机组结构剖析、循环热力计算和控制回路模拟等演示实验.实验系统采用友好的人机交互界面,便于操作和理解,既降低了学习难度,又提高了实验教学的效果.

  13. A language for easy and efficient modeling of Turing machines

    Institute of Scientific and Technical Information of China (English)

    Pinaki Chakraborty

    2007-01-01

    A Turing Machine Description Language (TMDL) is developed for easy and efficient modeling of Turing machines.TMDL supports formal symbolic representation of Turing machines. The grammar for the language is also provided. Then a fast singlepass compiler is developed for TMDL. The scope of code optimization in the compiler is examined. An interpreter is used to simulate the exact behavior of the compiled Turing machines. A dynamically allocated and resizable array is used to simulate the infinite tape of a Turing machine. The procedure for simulating composite Turing machines is also explained. In this paper, two sample Turing machines have been designed in TMDL and their simulations are discussed. The TMDL can be extended to model the different variations of the standard Turing machine.

  14. 基于动态局部更新体素模型的虚拟加工仿真算法研究%Research on Virtual Machining Simulation Algorithm Based on Dynamic Partial Rendering for Voxel Model

    Institute of Scientific and Technical Information of China (English)

    李妞; 陈成军; 陈韩燕

    2011-01-01

    为提高虚拟加工仿真算法的仿真速度和精度,提出一种新的基于动态局部更新体素模型的虚拟加工仿真算法.该算法利用体素节点间的邻接关系,实现虚拟加工仿真的动态局部更新.算法在初始化阶段建立虚拟毛坯的八叉树结构体素模型,并建立任意体素6-邻接关系遍历算法.在虚拟加工几何仿真阶段,利用刀具和毛坯相对运动的时空一致性,从毛坯上一帧已碰撞体素集向周围扩散依次检测其邻接体素是否与刀具发生碰撞,并根据碰撞情况动态修改已碰撞体素的参数,直到所有邻接体素均未与刀具发生碰撞,从而实现虚拟加工仿真的动态局部更新,提高了算法的速度与精度.最后通过铣削虚拟加工仿真验证本文所提出算法的可行性和有效性.%To improve the speed and accuracy of virtual machining simulation, a new algorithm of dynamic partial rendering for voxel model-based virtual machining simulation is proposed. It uses voxel adjacency relationship between nodes to achieve dynamic partial rendering. In initialization stage, both octree structure voxel model for virtual rough and adjacency traversal algorithm of any voxel are modeled. In stage of virtual machine simulation, the collision detection is conducted from voxels that collided with virtual tool in last frame, and spreads to their adjacent voxels calculated using adjacency traversal algorithm. If some tested voxel is collided with virtual tool, its parameter will be modified dynamically. So dynamic partial rendering in virtual machine simulation is realized. Finally, a simple five-axis milling virtual machining experiments is setted, which shows that the presented algorithm is feasible and effective.

  15. Machine Protection

    CERN Document Server

    Schmidt, R

    2014-01-01

    The protection of accelerator equipment is as old as accelerator technology and was for many years related to high-power equipment. Examples are the protection of powering equipment from overheating (magnets, power converters, high-current cables), of superconducting magnets from damage after a quench and of klystrons. The protection of equipment from beam accidents is more recent. It is related to the increasing beam power of high-power proton accelerators such as ISIS, SNS, ESS and the PSI cyclotron, to the emission of synchrotron light by electron–positron accelerators and FELs, and to the increase of energy stored in the beam (in particular for hadron colliders such as LHC). Designing a machine protection system requires an excellent understanding of accelerator physics and operation to anticipate possible failures that could lead to damage. Machine protection includes beam and equipment monitoring, a system to safely stop beam operation (e.g. dumping the beam or stopping the beam at low energy) and an ...

  16. 削边电极深小孔微细电火花间隙流场仿真研究%Gap Flow Simulation for Micro-EDM Deep-small Hole Machining with Flatted Electrode

    Institute of Scientific and Technical Information of China (English)

    张雷; 王玉魁; 耿雪松; 王振龙

    2011-01-01

    Machining of deep-small hole is one of the most important applications in micro-EDM.Usage of flatted electrodes is demonstrated to be an effective method in increasing the aspect - ratio in deep-small hole machining. The flow field simulation and experiments were taken out to investigate the reasons for higher aspect-ratio and efficiency of flatted electrodes.%深小孔加工是微细电火花加工的重要应用领域之一.采用削边电极加工是提高深小孔加工深径比的有效工艺手段之一.通过间隙流场仿真结合工艺实验,解释了削边电极深小孔加工提高深径比和加工速度的原因.

  17. 点钞机进钞机构动态分析和仿真研究%Dynamic analysis and simulation research on speed and stability of banknote feeding mechanism in cash-counting machine

    Institute of Scientific and Technical Information of China (English)

    刘明; 赵祚喜; 孙道宗; 刘雄; 施垒; 靳俊栋

    2015-01-01

    The blocking phenomenon of cash⁃counting machine is the main factor to affect the counting speed. The similar phenomenon also exists in the automatic teller machine,fax machine,printing machine and other media delivery systems. In or⁃der to solve this problem,taking the paper money feeding mechanism of HT⁃9000A type currency⁃counting machine as the re⁃search object,the dynamic behavior of the paper money feeding mechanism is simulated and analyzed. By using multi⁃body sys⁃tem dynamics simulation software RecurDyn,based on the geometric model of currency⁃counting machine’s transmission mecha⁃nism,the contact force between paper money and money entwisting wheel is analyzed. The results show that the money feeding angle range of 11.5°~12.5° can make the notes move in the ideal trajectory,make the machine keep stable note feeding speed, and make the occurrence probability of the blocking phenomenon reduced.%点钞机的卡钞现象是影响点钞速度的主要因素,这种类似现象也存在于传真机、自动取款机、冲印机等介质传送系统中。为解决该问题,以HT⁃9000A型点钞机的纸币进给机构为研究对象,仿真分析点钞机纸币在进钞机构中的动态行为,利用多体系统动力学仿真软件RecurDyn,根据建立的点钞机纸币传送机构的几何模型,分析在此过程中纸币与捻钞轮之间的接触力,对不同进钞角度的纸币运动速度以及运动轨迹进行运动仿真。结果表明选择11.5°~12.5°范围内的进钞角度能使纸币按照理想轨迹运动,同时能使纸币的进钞速度稳定,从而降低了卡钞现象发生的概率。

  18. Simulation Analysis on Brushless Doubly-Fed Machine of Cage Rotor with Deep Slots%深槽式笼型转子无刷双馈电机的仿真分析

    Institute of Scientific and Technical Information of China (English)

    胡堃; 何凤有; 薛冰

    2011-01-01

    针对笼型转子无刷双馈电机转子磁场调制能力差、电机效率低特点,利用Ansofi软件对一种新型深槽式笼型转子无刷双馈电机进行建模仿真,得出电机磁力线分布图,气隙磁通密度波形,再利用MATLAB软件计算出气隙磁通谐波含量,与具有较好磁场调制能力的凸极加导条转子无刷双馈电机的仿真结果进行分析对比,得出深槽式笼型转子结构简单可靠,具有更高的磁场极数转换效率.%For the brushless doubly-fed machine with cage rotor has poor rotor magnetic modulation ability and low efficiency ,a brushless doubly-fed machine which had a kind of new cage rotor with deep slots was modeled and simulated by Ansoft that gets the results of distribution of magnetic force line and density wave of air-gap magnetic fields. The harmonic content of air-gap magnetic fields was calculated with MATLAB and the simulation results of the new cage rotor and the brushless doubly-fed machine with the salient poles rotor with bars which had a good ability of magnetic modulation were compared. The results show that the brushless doubly-fed machine which has a kind of new cage rotor with deep slots has a simple and reliable structure and a better efficiency of rotor magnetic field pole-number conversion.

  19. Analysis of machining and machine tools

    CERN Document Server

    Liang, Steven Y

    2016-01-01

    This book delivers the fundamental science and mechanics of machining and machine tools by presenting systematic and quantitative knowledge in the form of process mechanics and physics. It gives readers a solid command of machining science and engineering, and familiarizes them with the geometry and functionality requirements of creating parts and components in today’s markets. The authors address traditional machining topics, such as: single and multiple point cutting processes grinding components accuracy and metrology shear stress in cutting cutting temperature and analysis chatter They also address non-traditional machining, such as: electrical discharge machining electrochemical machining laser and electron beam machining A chapter on biomedical machining is also included. This book is appropriate for advanced undergraduate and graduate mechani cal engineering students, manufacturing engineers, and researchers. Each chapter contains examples, exercises and their solutions, and homework problems that re...

  20. Using Phun to Study ``Perpetual Motion'' Machines

    Science.gov (United States)

    Koreš, Jaroslav

    2012-05-01

    The concept of "perpetual motion" has a long history. The Indian astronomer and mathematician Bhaskara II (12th century) was the first person to describe a perpetual motion (PM) machine. An example of a 13th- century PM machine is shown in Fig. 1. Although the law of conservation of energy clearly implies the impossibility of PM construction, over the centuries numerous proposals for PM have been made, involving ever more elements of modern science in their construction. It is possible to test a variety of PM machines in the classroom using a program called Phun2 or its commercial version Algodoo.3 The programs are designed to simulate physical processes and we can easily simulate mechanical machines using them. They provide an intuitive graphical environment controlled with a mouse; a programming language is not needed. This paper describes simulations of four different (supposed) PM machines.4

  1. Machining Movement Track Simulation for Robot of EDM Curved Hole%曲线孔电火花加工机器人加工运动轨迹模拟

    Institute of Scientific and Technical Information of China (English)

    刘永红; 李庆云; 杨毅

    2001-01-01

    The mechanism and principle of peristalsis for robot of EDM curved hole are discussed in this paper.The simulation system for machining movement track of robot of EDM curved hole is developed by object-oriented methodology and Visual C++6 language.Using the simulation system,machining movement gesture and movement track for robot of EDM curved hole can expediently simulated.%该文论述了曲线孔电火花加工机器人的机构组成和蠕动原理,采用面向对象技术和Visual C++6语言开发出了曲线孔电火花加工机器人的加工运动轨迹模拟系统,采用该系统可方便地模拟出电火花加工机器人加工任意曲线孔时的运动姿态和运动轨迹。

  2. Targeting glucose metabolism in cancer: new class of agents for loco-regional and systemic therapy of liver cancer and beyond?

    Science.gov (United States)

    Savic, Lynn Jeanette; Chapiro, Julius; Duwe, Gregor; Geschwind, Jean-François

    2016-01-01

    Hepatocellular carcinoma (HCC) is one of the most prevalent cancers and the third leading cause of cancer-related deaths worldwide. In patients with unresectable disease, loco-regional catheter-based intra-arterial therapies (IAT) can achieve selective tumor control while minimizing systemic toxicity. As molecular features of tumor growth and microenvironment are better understood, new targets arise for selective anticancer therapy. Particularly, antiglycolytic drugs that exploit the hyperglycolytic cancer cell metabolism – also known as the ‘Warburg effect’ – have emerged as promising therapeutic options. Thus, future developments will combine the selective character of loco-regional drug delivery platforms with highly specific molecular targeted antiglycolytic agents. This review will exemplify literature on antiglycolytic approaches and particularly focus on intra-arterial delivery methods. PMID:26989470

  3. Targeting glucose metabolism in cancer: new class of agents for loco-regional and systemic therapy of liver cancer and beyond?

    Science.gov (United States)

    Savic, Lynn Jeanette; Chapiro, Julius; Duwe, Gregor; Geschwind, Jean-François

    2016-01-01

    Hepatocellular carcinoma (HCC) is one of the most prevalent cancers and the third leading cause of cancer-related deaths worldwide. In patients with unresectable disease, loco-regional catheter-based intra-arterial therapies (IAT) can achieve selective tumor control while minimizing systemic toxicity. As molecular features of tumor growth and microenvironment are better understood, new targets arise for selective anticancer therapy. Particularly, antiglycolytic drugs that exploit the hyperglycolytic cancer cell metabolism - also known as the 'Warburg effect' - have emerged as promising therapeutic options. Thus, future developments will combine the selective character of loco-regional drug delivery platforms with highly specific molecular targeted antiglycolytic agents. This review will exemplify literature on antiglycolytic approaches and particularly focus on intra-arterial delivery methods.

  4. Identifying appropriate spatial scales for marine conservation and management using a larval dispersal model: The case of Concholepas concholepas (loco) in Chile

    Science.gov (United States)

    Garavelli, Lysel; Kaplan, David Michael; Colas, François; Stotz, Wolfgang; Yannicelli, Beatriz; Lett, Christophe

    2014-05-01

    Along the coast of Chile, fisheries targeting the marine gastropod Concholepas concholepas, commonly named “loco”, were highly valuable until the end of the 80s when catches declined significantly. Since the late 90s, a management plan based on territorial-user-rights areas has been implemented, with limited effect on stock recovery. More effective loco conservation and management is impeded by lack of information regarding connectivity via larval dispersal between these individually-managed areas. To develop a regional view of loco connectivity, we integrate loco life history information into a biophysical, individual-based larval dispersal model. This model is used to evaluate scales of loco connectivity and seasonality in connectivity patterns, as well as to partition the coast into largely disconnected subpopulations using a recently developed connectivity-matrix clustering algorithm. We find mean dispersal distances ranging from 170 to 220 km depending on release depth of larvae and planktonic larval duration. Settlement success levels depend quantitatively on the physical and biological processes included in the model, but connectivity patterns remain qualitatively similar. Model estimates of settlement success peak for larval release dates in late austral autumn, consistent with field results and with favorable conditions for larval coastal retention due to weak upwelling during austral autumn. Despite the relatively homogeneous Chilean coastline, distinct subpopulations with minimal connectivity between them are readily identifiable. Barriers to connectivity that are robust to changes in model configuration exist at 23°S and 29°S latitudes. These zones are all associated with important headlands and embayments of the Chilean coast.

  5. Automation of printing machine

    OpenAIRE

    Sušil, David

    2016-01-01

    Bachelor thesis is focused on the automation of the printing machine and comparing the two types of printing machines. The first chapter deals with the history of printing, typesettings, printing techniques and various kinds of bookbinding. The second chapter describes the difference between sheet-fed printing machines and offset printing machines, the difference between two representatives of rotary machines, technological process of the products on these machines, the description of the mac...

  6. Simulations

    CERN Document Server

    Ngada, N M

    2015-01-01

    The complexity and cost of building and running high-power electrical systems make the use of simulations unavoidable. The simulations available today provide great understanding about how systems really operate. This paper helps the reader to gain an insight into simulation in the field of power converters for particle accelerators. Starting with the definition and basic principles of simulation, two simulation types, as well as their leading tools, are presented: analog and numerical simulations. Some practical applications of each simulation type are also considered. The final conclusion then summarizes the main important items to keep in mind before opting for a simulation tool or before performing a simulation.

  7. Active chatter control in a milling machine

    Energy Technology Data Exchange (ETDEWEB)

    Dohner, J.L.; Hinnerichs, T.D.; Lauffer, J.P. [and others

    1997-08-01

    The use of active feedback compensation to mitigate cutting instabilities in an advanced milling machine is discussed in this paper. A linear structural model delineating dynamics significant to the onset of cutting instabilities was combined with a nonlinear cutting model to form a dynamic depiction of an existing milling machine. The model was validated with experimental data. Modifications made to an existing machine model were used to predict alterations in dynamics due to the integration of active feedback compensation. From simulations, subcomponent requirements were evaluated and cutting enhancements were predicted. Active compensation was shown to enable more than double the metal removal rate over conventional milling machines. 25 refs., 10 figs., 1 tab.

  8. MiR-422a promotes loco-regional recurrence by targeting NT5E/CD73 in head and neck squamous cell carcinoma.

    Science.gov (United States)

    Bonnin, Nathalie; Armandy, Emma; Carras, Julien; Ferrandon, Sylvain; Battiston-Montagne, Priscillia; Aubry, Marc; Guihard, Sébastien; Meyronet, David; Foy, Jean-Philippe; Saintigny, Pierre; Ledrappier, Sonia; Jung, Alain; Rimokh, Ruth; Rodriguez-Lafrasse, Claire; Poncet, Delphine

    2016-07-12

    At the time of diagnosis, 60% of patients with head and neck squamous cell carcinoma (HNSCC) present tumors in an advanced stage (III-IV) of disease and 80% will relapse within the first two years post-treatment, due to their frequent radio(chemo)resistance. To identify new molecular targets and companion biomarkers, we have investigated the miRNome of 75 stage III-IV oropharynx tumors without relapse (R) or with loco-regional relapse (non-responder, NR) within two years post-treatment. Interestingly, miR-422a was significantly downregulated in NR tumors, in agreement with the increase in cell proliferation and adhesion induced by miR-422a inhibition in vitro. Furthermore, we identified CD73/NT5E oncogene as target of miR-422a. Indeed, modulation of the endogenous level of miR-422a inversely influences the expression and the enzymatic activity of CD73. Moreover, knocking down CD73 mimics the effects of miR-422a upregulation. Importantly, in tumors, miR-422a and CD73 expression levels are inversely correlated, and both are predictive of relapse free survival - especially considering loco(regional) recurrence - in vitro two independent cohorts of advanced oropharynx or HNSCC (N=255) tumors. In all, we reported, for the first time, that MiR-422a and its target CD73 are involved in early loco(regional) recurrence of HNSCC tumors and are new targets for personalized medicine.

  9. Spectrum Assignment Algorithm for Cognitive Machine-to-Machine Networks

    Directory of Open Access Journals (Sweden)

    Soheil Rostami

    2016-01-01

    Full Text Available A novel aggregation-based spectrum assignment algorithm for Cognitive Machine-To-Machine (CM2M networks is proposed. The introduced algorithm takes practical constraints including interference to the Licensed Users (LUs, co-channel interference (CCI among CM2M devices, and Maximum Aggregation Span (MAS into consideration. Simulation results show clearly that the proposed algorithm outperforms State-Of-The-Art (SOTA algorithms in terms of spectrum utilisation and network capacity. Furthermore, the convergence analysis of the proposed algorithm verifies its high convergence rate.

  10. The Structure Design and Simulation Analysis of New Type Banana Planting Open Pit Machine%新型香蕉种植开坑机的结构设计与仿真分析

    Institute of Scientific and Technical Information of China (English)

    娄玉印; 张林

    2017-01-01

    Based on the principle of reduce labor costs, improve labor efficiency, this paper developed a controllable connecting rod type 3-dof new banana planting open pit machine. First of all, through the formula based on screw theory based on the degrees of freedom, calculates the controllable banana planting open pit machine freedom, Secondly, ba-nana planting open pit machine was established by applying the method of closed loop vector controlled the kinematics e-quation of earth auger, it is concluded that the kinematics characteristic;finally, combining with the multi-body dynam-ics theory combined with ADAMS software, simulation analysis was carried out on the controlled banana planting open pit machine, it is concluded that the engine movement characteristics. The results verify the rationality and feasibility of the new type of structure.%基于降低减轻人力成本、提高劳动效率的原则,研发了一种可控连杆式三自由度香蕉种植开坑机。首先,通过基于旋量理论为基础的自由度公式,计算出可控香蕉种植开坑机自由度;其次,运用闭环矢量法建立了可控香蕉种植开坑机的运动学方程,得出其运动学特性;最后,结合多体动力学理论及 ADAMS 软件,对可控香蕉种植开坑机进行仿真分析,得出其发动机运动特性,进而验证了该新型结构的合理性和可行性。

  11. 基于Deform-3D的65Mn硬态切削加工仿真研究%Simulation Study on Hard Cutting Machining Based on Deform-3D

    Institute of Scientific and Technical Information of China (English)

    赵晶晶; 覃寿同; 林强; 王栋; 张银霞; 李松涛; 段闪闪; 李荣鑫

    2014-01-01

    以淬硬钢65Mn为原料,采用有限元分析软件Deform⁃3D构建了硬态切削加工模型。模拟了不同切削速度下淬硬钢65Mn的车削加工过程,对车削加工的切削力、温度随切削速度的提高的变化以及工件表面应力变化的仿真结果给出了分析,为实现工艺参数的优化提供了指导。结果表明:硬态切削加工3个切削力中径向力Fy 最大,第二变形区的切削温度较高,硬态切削加工过程中工件表面应力呈现拉压交替变换且最终表现为压应力。%With hardened steel 65Mn as raw material, by using the finite element analysis ( FEA) software Deform⁃3D, the hard machining of hardened steel model was constructed. The different cutting speeds for turning hardened steel 65Mn process were simula⁃ted, and the simulation results of cutting forces and cutting temperature and surface stress were analyzed in changes with increasing of the cutting speed and temperature during turning machining, which provided guidance for realizing optimization of process parameters. The results show that the maximum cutting force is the radial cutting force Fy in hard machining among three. The second deformation zone shows higher temperature. During the hard machining process, the tensile and compressive stress alternate on the surface of the workpiece. Finally, the surface of the workpiece presents compressive stress.

  12. Machine musicianship

    Science.gov (United States)

    Rowe, Robert

    2002-05-01

    The training of musicians begins by teaching basic musical concepts, a collection of knowledge commonly known as musicianship. Computer programs designed to implement musical skills (e.g., to make sense of what they hear, perform music expressively, or compose convincing pieces) can similarly benefit from access to a fundamental level of musicianship. Recent research in music cognition, artificial intelligence, and music theory has produced a repertoire of techniques that can make the behavior of computer programs more musical. Many of these were presented in a recently published book/CD-ROM entitled Machine Musicianship. For use in interactive music systems, we are interested in those which are fast enough to run in real time and that need only make reference to the material as it appears in sequence. This talk will review several applications that are able to identify the tonal center of musical material during performance. Beyond this specific task, the design of real-time algorithmic listening through the concurrent operation of several connected analyzers is examined. The presentation includes discussion of a library of C++ objects that can be combined to perform interactive listening and a demonstration of their capability.

  13. Loco-regional control after neo-adjuvant chemotherapy and conservative treatment for locally advanced breast cancer patients.

    Science.gov (United States)

    Levy, Antonin; Borget, Isabelle; Bahri, Manel; Arnedos, Monica; Rivin, Eleonor; Vielh, Philippe; Balleyguier, Corinne; Rimareix, Françoise; Bourgier, Céline

    2014-01-01

    Breast-conserving treatment (BCT) has been validated for breast cancer patients receiving adjuvant chemotherapy. Our objective was to evaluate the difference in loco-regional recurrence (LRR) rates between BCT and mastectomy in patients receiving radiation therapy after neo-adjuvant chemotherapy (NCT). A retrospective data base was used to identify all patients with breast cancer undergoing NCT from 2002 to 2007. Patients with initial metastatic disease were excluded from this analysis. LRR was compared between those undergoing BCT and mastectomy. Individual variables associated with LRR were evaluated. Two hundred eighty-four patients were included, 111 (39%) underwent BCT and 173 (61%) mastectomy. Almost all patients (99%) in both groups received postoperative radiation. Pathologic complete response was seen in 37 patients, of which 28 underwent BCT (p loco-regional control rate was 91% (95% CI: 86-94%). The 10-year LRR rate was similar in the BCT group (9.2% [95% CI: 4.9-16.7%]) and in the mastectomy group (10.7% [95% CI: 5.9-15.2%]; p = 0.8). Ten-year overall survival (OS) rates (63% [95% CI: 46-79%] in the BCT group; 60% [95% CI: 47-73%] in the mastectomy group, p = 0.8) were not statistically different between the two patient populations. Multivariate analysis showed that AJCC stage ≥ III (HR: 2.6; 95% CI: 1.2-5.8; p = 0.02), negative PR (HR: 6; 95% CI: 1.2-30.6, p = 0.03), and number of positive lymph nodes ≥3 (HR: 2.5; 95% CI: 1.1-5.9; p = 0.03) were independent predictors of LRR. Ten-year OS was similar in the BCT and in the mastectomy group (p = 0.1). The rate of LRR was low and did not significantly differ between the BCT and the mastectomy group after NCT. Randomized trials assessing whether mastectomy can be safely omitted in selected breast cancer patients (nonstage III tumors or those which do not require adjuvant hormone suppression) which respond to NCT are required.

  14. Tensor Network Quantum Virtual Machine (TNQVM)

    Energy Technology Data Exchange (ETDEWEB)

    2016-11-18

    There is a lack of state-of-the-art quantum computing simulation software that scales on heterogeneous systems like Titan. Tensor Network Quantum Virtual Machine (TNQVM) provides a quantum simulator that leverages a distributed network of GPUs to simulate quantum circuits in a manner that leverages recent results from tensor network theory.

  15. 耕种机虚拟样机精密单体播深和排种仿真研究%Simulation Research on Precision Monomer Sowing Depth and Seed Metering of Farming Machine Virtual Prototype

    Institute of Scientific and Technical Information of China (English)

    王风燕; 马茵; 刘志刚

    2016-01-01

    In order to further improve the farming machine sowing depth control and metering accuracy, improve the de-sign efficiency of farming machine, put forward a kind of optimization design method of machine for tilling seeding accu-racy numerical simulation based on the virtual prototype model, established the seeder, and the optimization effect on seeding parameters calculated simulation.The seeding machine parts design using three-dimensional drawing software UG, assembly model is established, the design of the virtual prototype model of precision seeder, the metering device for precision seeding machine virtual prototype and the qualified rate of the sowing depth of dynamic simulation is carried out using ADAMS software.Through the numerical simulation calculation, the precise sowing machine get deep variation curves, obtained ADAMS parameters before and after optimization, the metering accuracy and sowing depth qualified rate results.The results found, sowing precision after optimization is improved obviously, and the coefficient of variation is small , the virtual prototype of the sowing depth pass rate has been significantly improved, and the sowing depth control of good stability, high control precision sowing depth, provide technical reference for optimization design of seeder the.%为了进一步改善耕种机的播深控制和排种精度,提高耕种机的设计效率,提出了一种基于数值仿真模拟的耕种机播种精度优化设计方法,建立了播种机的虚拟样机模型,并对播种参数的优化效果进行了仿真计算分析。利用三维绘图软件UG设计了排种器的零部件,建立了装配模型,设计了精密播种机的虚拟样机模型;采用ADAMS软件对排种器排种精度和播种机虚拟样机的播深合格率进行了动力学仿真。通过数值仿真模拟计算,得到了精密播种机播深随时间的变化曲线,以及ADAMS参数优化前后排种精度和播深合格率的结果。通

  16. A new approach to theoretical investigations of high harmonics generation by means of fs laser interaction with overdense plasma layers. Combining particle-in-cell simulations with machine learning.

    Science.gov (United States)

    Mihailescu, A.

    2016-12-01

    Within the past decade, various experimental and theoretical investigations have been performed in the field of high-order harmonics generation (HHG) by means of femtosecond (fs) laser pulses interacting with laser produced plasmas. Numerous potential future applications thus arise. Beyond achieving higher conversion efficiency for higher harmonic orders and hence harmonic power and brilliance, there are more ambitious scientific goals such as attaining shorter harmonic wavelengths or reducing harmonic pulse durations towards the attosecond and even the zeptosecond range. High order harmonics are also an attractive diagnostic tool for the laser-plasma interaction process itself. Particle-in-Cell (PIC) simulations are known to be one of the most important numerical instruments employed in plasma physics and in laser-plasma interaction investigations. The novelty brought by this paper consists in combining the PIC method with several machine learning approaches. For predictive modelling purposes, a universal functional approximator is used, namely a multi-layer perceptron (MLP), in conjunction with a self-organizing map (SOM). The training sets have been retrieved from the PIC simulations and also from the available literature in the field. The results demonstrate the potential utility of machine learning in predicting optimal interaction scenarios for gaining higher order harmonics or harmonics with particular features such as a particular wavelength range, a particular harmonic pulse duration or a certain intensity. Furthermore, the author will show how machine learning can be used for estimations of electronic temperatures, proving that it can be a reliable tool for obtaining better insights into the fs laser interaction physics.

  17. Motion Simulation of 3-TPT Virtual-axis Machine Based on ActiveX Technology%基于ActiveX技术的3-TPT并联虚轴机床运动仿真

    Institute of Scientific and Technical Information of China (English)

    盛忠起; 孙奕澎; 蔡光起

    2001-01-01

    根据最新研制的3-TPT并联虚轴机床的机构组成,对其进行了运动分析,建立了虚轴机床的运动模型,并得到了并联机构的运动学逆解表达式,同时还得到了该并联机构的运动学正解表达式利用MDT提供的ActiveX操作机制,应用面向对象方法和ActiveX技术,进行了3-TPT并联虚轴机床的运动仿真,提出了运动仿真的具体实施方法和过程*在Visual Basic开发环境下,完成了仿真程序编制工作通过实际仿真证明:该并联机构具有运动学正反计算简单、易于实现实时控制及工作空间大等优点%The kinematics character of the 3-TPT in-parallel mechanism of virtual-axis machine was analyzed. The kinematics model of virtual-axis machine was given. Based on the model,the explicit kinematics reverse formula and forward formula were obtained together. Using the ActiveX operation mechanism provided by MDT and object oriented-based method,the motion simulation method of 3-TPT virtual-axis machine was studied and the specific procedure was given. The procedure is programmed in Visual Basic environment. By simulation analysis this kind of 3-TPT in-parallel mechanism proves to be simple and has explicit forward & reverse kinematics formula,by which real-time motion control can be realized easily.

  18. Electrical machines mathematical fundamentals of machine topologies

    CERN Document Server

    Gerling, Dieter

    2015-01-01

    Electrical Machines and Drives play a powerful role in industry with an ever increasing importance. This fact requires the understanding of machine and drive principles by engineers of many different disciplines. Therefore, this book is intended to give a comprehensive deduction of these principles. Special attention is given to the precise mathematical derivation of the necessary formulae to calculate machines and drives and to the discussion of simplifications (if applied) with the associated limits. The book shows how the different machine topologies can be deduced from general fundamentals, and how they are linked together. This book addresses graduate students, researchers, and developers of Electrical Machines and Drives, who are interested in getting knowledge about the principles of machine and drive operation and in detecting the mathematical and engineering specialties of the different machine and drive topologies together with their mutual links. The detailed - but nevertheless compact - mat...

  19. VIRTUAL MACHINES IN EDUCATION – CNC MILLING MACHINE WITH SINUMERIK 840D CONTROL SYSTEM

    Directory of Open Access Journals (Sweden)

    Ireneusz Zagórski

    2014-11-01

    Full Text Available Machining process nowadays could not be conducted without its inseparable element: cutting edge and frequently numerically controlled milling machines. Milling and lathe machining centres comprise standard equipment in many companies of the machinery industry, e.g. automotive or aircraft. It is for that reason that tertiary education should account for this rising demand. This entails the introduction into the curricula the forms which enable visualisation of machining, milling process and virtual production as well as virtual machining centres simulation. Siemens Virtual Machine (Virtual Workshop sets an example of such software, whose high functionality offers a range of learning experience, such as: learning the design of machine tools, their configuration, basic operation functions as well as basics of CNC.

  20. Application of FEA Simulation Analysis in Sewing Machine Developing%有限元仿真分析在缝纫机开发中的应用研究

    Institute of Scientific and Technical Information of China (English)

    王文广; 李莉敏

    2004-01-01

    CAE仿真分析在整个产品生命周期都发挥着重要作用,为企业创造巨大的效益.本文利用UG工具对缝纫机机构进行仿真分析,仿真分析的结果对产品设计工程师进行产品设计有很大的指导意义.%CAE simulation analysis plays an important role in the product whole life cycle and can make great profits for company. This paper carries out simulation analysis on a type of sewing machine using the unigraphics software. The results of analysis have instructional meanings to product design engineer in design progress.

  1. Finite-state machines as elements in control systems.

    Science.gov (United States)

    Burgin, G. H.; Walsh, M. J.

    1971-01-01

    Demonstration that approximate solutions to certain classes of differential and difference equations can be expressed in form of finite state machines. Based on this result, a finite-state machine model of an adaptive gain changer in an aircraft stability augmentation system is developed. Results of simulated flights using the finite-state machine gain changer are presented.

  2. Laser machining of advanced materials

    CERN Document Server

    Dahotre, Narendra B

    2011-01-01

    Advanced materialsIntroductionApplicationsStructural ceramicsBiomaterials CompositesIntermetallicsMachining of advanced materials IntroductionFabrication techniquesMechanical machiningChemical Machining (CM)Electrical machiningRadiation machining Hybrid machiningLaser machiningIntroductionAbsorption of laser energy and multiple reflectionsThermal effectsLaser machining of structural ceramicsIntrodu

  3. Research on Virtual Five-axis CNC Tool Grinder Machining Simulation Technology%五轴数控工具磨床的虚拟加工仿真技术研究

    Institute of Scientific and Technical Information of China (English)

    张哲山; 姚斌; 陆如升; 李飞; 姚博世

    2011-01-01

    The design process of a virtual machining environment for five-axis CNC tool grinder based on the tesearch of the computer aided design and virtual prototype technology has been presented in this paper.This simulation platform is very adapt to the early verification of helical cutter design and manufacturing .And the correctness of NC processing commands can also checkec on this simulation platform.Taking the end mill as an example,the manufacturing process was simulated . The simulation results show that the virtual modeling method is feasible and the result can effectively judge the mutual interference of machine tool system.This method also can imperove the reliability of NC commands.%通过计算机辅助设计与虚拟样机技术,建市了五轴数控工具磨床虚拟加工环境.借助这个平台对回转面刀具进行了设计制造的前期验证,检验加工指令的准确与否.最后以两刃立铣刀为例,利用生成的数控加工程序对其进行了虚拟仿真磨削,结果证明了研究理论的可行性和准确性.同时,加工仿真可有效判断机床工艺系统的相互干涉问题,提高了数控指令的可靠性.

  4. Analytic Simulation of Transient Stability of Infinitely Great Electric Power System of a Single Machine%某单机无穷大电力系统暂态稳定性分析仿真

    Institute of Scientific and Technical Information of China (English)

    许江博; 韩宏亮; 张双平

    2012-01-01

    Electric power system is a complicated dynamical system, which may cause serious result in a short time when stability problem occurs. Therefore, large amount of transient stability analysis is necessary in planning, designing and operating works of electric power system. This article Introduced power system time domain simulation mathematical model, construction of a single machine infinite bus system simulation model. It constructs infinitely great system model of single machine applying simulated model, and the result of simulation shows that: the shorter the fault cleaning time is, and the greater the damping of electric generator is, the more stable the system is; When single phase short circuit ground fault occurs,the system can achieve the most stable condition.%电力系统是一个复杂的动态系统,系统一旦出现稳定性问题,可能会在较短的时间内发生严重后果,因此,在电力系统规划、设计、运行等工作中都要进行大量的暂态稳定分析。介绍了电力系统时域仿真数学模型,构建了单机无穷大系统仿真模型。仿真结果表明:故障切除时间越短,发电机阻尼越大,系统越容易稳定,且在单相短路接地故障情况下系统最容易稳定。

  5. An autoinhibited conformation of LGN reveals a distinct interaction mode between GoLoco motifs and TPR motifs.

    Science.gov (United States)

    Pan, Zhu; Zhu, Jinwei; Shang, Yuan; Wei, Zhiyi; Jia, Min; Xia, Caihao; Wen, Wenyu; Wang, Wenning; Zhang, Mingjie

    2013-06-01

    LGN plays essential roles in asymmetric cell divisions via its N-terminal TPR-motif-mediated binding to mInsc and NuMA. This scaffolding activity requires the release of the autoinhibited conformation of LGN by binding of Gα(i) to its C-terminal GoLoco (GL) motifs. The interaction between the GL and TPR motifs of LGN represents a distinct GL/target binding mode with an unknown mechanism. Here, we show that two consecutive GL motifs of LGN form a minimal TPR-motif-binding unit. GL12 and GL34 bind to TPR0-3 and TPR4-7, respectively. The crystal structure of a truncated LGN reveals that GL34 forms a pair of parallel α helices and binds to the concave surface of TPR4-7, thereby preventing LGN from binding to other targets. Importantly, the GLs bind to TPR motifs with a mode distinct from that observed in the GL/Gα(i)·GDP complexes. Our results also indicate that multiple and orphan GL motif proteins likely respond to G proteins with distinct mechanisms.

  6. Influence of back-gate stress on the back-gate threshold voltage of a LOCOS-isolated SOI MOSFET

    Institute of Scientific and Technical Information of China (English)

    梅博; 毕津顺; 李多力; 刘思南; 韩郑生

    2012-01-01

    The performance of a LOCOS-isolated SOI MOSFET heavily depends on its back-gate characteristic, which can be affected by back-gate stress,A large voltage stress was applied to the back gate of SOI devices for at least 30 s at room temperature,which could effectively modify the back-gate threshold voltage of these devices.This modification is stable and time invariant.In order to improve the back-gate threshold voltage,positive substrate bias was applied to NMOS devices and negative substrate bias was applied to PMOS devices,These results suggest that there is a leakage path between source and drain along the silicon island edge,and the application of large backgate bias with the source,drain and gate grounded can strongly affect this leakage path.So we draw the conclusion that the back-gate threshold voltage,which is directly related to the leakage current,can be influenced by back-gate stress.

  7. Local coupling (LoCo) vs. large-scale coupled (LsCo) land-atmosphere interactions in idealized experiments

    Science.gov (United States)

    Gentine, P.; Lintner, B. R.; Findell, K. L.; Rochetin, N.; Sobel, A. H.; Anber, U. M.

    2014-12-01

    We will present two idealized epxeriments/methodologies to investigate local (LoCo) and large-scale (LsCo) coupling between the surface and the atmsophere: the contiental Radiative-Convective Equilibrium (RCE) and the continental Weak Temperature Gradient (WTG). The RCE defines an equilibrium state of coupling between the surafce and the atmosphere isolated from any large-scale dependence, which were investigated within the single column model of the Laboratoire de Meteorologie Dynamique (LMD) coupled to a simple bucket land model. This studies emphasizes the role of low-level cloud and the diurnal cylce of the boundary layer on the final state of the system. In the WTG we investigate the coupling between the surface and the atmosphere during the dry and wet season of the Amazon with the WRF model coupled to the NOAH land-surface model. Large-scale coupling is obtained with the WTG. The dry and wet season demonstrate very fundamental behavior: in the dry season deep convection is generated by radiative cooling in the higher troposhere and is disconnected from the surface. In the wet season the coupling between the surface and the atmosphere is much tighter. We suggest that the WTG is a powerful tool to investigate the coupling between the surface and the atmosphere, which solves two major issues: the limited resolution of convection in GCMs and the lack of large-scale coupling in CRM. Later investigation will look at the effect of deforestation, water table and distance from the ocean.

  8. The deleuzian abstract machines

    DEFF Research Database (Denmark)

    Werner Petersen, Erik

    2005-01-01

    production. In Kafka: Toward a Minor Literature, Deleuze and Guatari gave the most comprehensive explanation to the abstract machine in the work of art. Like the war-machines of Virilio, the Kafka-machine operates in three gears or speeds. Furthermore, the machine is connected to spatial diagrams...

  9. Applications and modelling of bulk HTSs in brushless ac machines

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, G.J. [Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ (United Kingdom). E-mail: gary.barnes at eng.ox.ac.uk; McCulloch, M.D.; Dew-Hughes, D. [Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ (United Kingdom)

    2000-06-01

    The use of high temperature superconducting material in its bulk form for engineering applications is attractive due to the large power densities that can be achieved. In brushless electrical machines, there are essentially four properties that can be exploited; their hysteretic nature, their flux shielding properties, their ability to trap large flux densities and their ability to produce levitation. These properties translate to hysteresis machines, reluctance machines, trapped-field synchronous machines and linear motors respectively. Each one of these machines is addressed separately and computer simulations that reveal the current and field distributions within the machines are used to explain their operation. (author)

  10. Applications and modelling of bulk HTSs in brushless ac machines

    Science.gov (United States)

    Barnes, G. J.; McCulloch, M. D.; Dew-Hughes, D.

    2000-06-01

    The use of high temperature superconducting material in its bulk form for engineering applications is attractive due to the large power densities that can be achieved. In brushless electrical machines, there are essentially four properties that can be exploited; their hysteretic nature, their flux shielding properties, their ability to trap large flux densities and their ability to produce levitation. These properties translate to hysteresis machines, reluctance machines, trapped-field synchronous machines and linear motors respectively. Each one of these machines is addressed separately and computer simulations that reveal the current and field distributions within the machines are used to explain their operation.

  11. Dynamic thermal analysis of machines in running state

    CERN Document Server

    Wang, Lihui

    2014-01-01

    With the increasing complexity and dynamism in today’s machine design and development, more precise, robust and practical approaches and systems are needed to support machine design. Existing design methods treat the targeted machine as stationery. Analysis and simulation are mostly performed at the component level. Although there are some computer-aided engineering tools capable of motion analysis and vibration simulation etc., the machine itself is in the dry-run state. For effective machine design, understanding its thermal behaviours is crucial in achieving the desired performance in real situation. Dynamic Thermal Analysis of Machines in Running State presents a set of innovative solutions to dynamic thermal analysis of machines when they are put under actual working conditions. The objective is to better understand the thermal behaviours of a machine in real situation while at the design stage. The book has two major sections, with the first section presenting a broad-based review of the key areas of ...

  12. Simulation Research of Brushless Doubly-fed Machines with Different Rotor Structures%不同转子结构无刷双馈电动机的仿真研究

    Institute of Scientific and Technical Information of China (English)

    薛冰; 胡堃; 樊贝

    2012-01-01

    Working principle of brushless doubly-fed machine and characteristics of different kinds of rotor structures were introduced, and brushless doubly-fed machines with four kinds of rotor structures were modeled and simulated by Ansoft software including reluctance rotor, cage rotor, salient poles rotor and salient poles rotor with bars. The results of distribution of magnetic force lines and frequency spectrum of air-gap magnetic field harmonic of the brushless doubly-fed machines were gotten through 2D transient electromagnetic field finite element, which indicate effects of rotor structures on magnetic field modulation of brushless doubly-fed machines. The final conclusion was the reluctance rotor has the best effect on magnetic field modulation and the cage rotor has the worst effect, which provides foundation for optimal design of rotor structure of brushless doubly-fed machine.%阐述了无刷双馈电动机的工作原理和不同转子结构特点,采用Ansoft软件对磁障、笼型、凸极、凸极加导条4种不同转子结构的无刷双馈电动机进行了建模仿真,通过二维瞬态电磁场有限元计算出了不同转子结构无刷双馈电动机的磁力线分布及气隙磁场谐波的频谱图,揭示了不同转子结构对无刷双馈电动机磁场调制效果的影响,得出磁障转子无刷双馈电动机对磁场的调制效果最好、笼型转子无刷双馈电动机对磁场的调制效果最差的结论,为深入研究无刷双馈电动机转子结构的优化设计奠定了基础.

  13. The complexity of small universal Turing machines: a survey

    CERN Document Server

    Neary, Turlough

    2011-01-01

    We survey some work concerned with small universal Turing machines, cellular automata, tag systems, and other simple models of computation. For example it has been an open question for some time as to whether the smallest known universal Turing machines of Minsky, Rogozhin, Baiocchi and Kudlek are efficient (polynomial time) simulators of Turing machines. These are some of the most intuitively simple computational devices and previously the best known simulations were exponentially slow. We discuss recent work that shows that these machines are indeed efficient simulators. In addition, another related result shows that Rule 110, a well-known elementary cellular automaton, is efficiently universal. We also discuss some old and new universal program size results, including the smallest known universal Turing machines. We finish the survey with results on generalised and restricted Turing machine models including machines with a periodic background on the tape (instead of a blank symbol), multiple tapes, multipl...

  14. Simulation Analysis on Magnetic Saturation of Induction Machine%异步电机磁路饱和仿真研究

    Institute of Scientific and Technical Information of China (English)

    杜肖飞; 郭农生; 周元钧

    2014-01-01

    在航空变频电源供电下,航空异步电动机在额定状态时或低频供电时存在磁路饱和的现象,一定程度的饱和有利于提高电磁转矩,但是过度饱和将导致电机定子电流出现畸变及谐波,异步电机生成的谐波电流将对飞机供电系统的电能质量产生不利影响。采用一台在115 V/600 Hz电源供电下的鼠笼式异步电机模型进行有限元仿真,分别计算齿部、轭部以及气隙磁密增大情况所产生的电流饱和谐波,分析饱和时的气隙磁密、齿部及轭部磁密,采用傅里叶变换计算饱和电流谐波,从而建立电流谐波分量与不同饱和情况的关系,通过比较三种饱和情况生成的电流谐波分量,提出抑制高次电流谐波的设计思路。%Aero induction machines are magnetically saturated when working with aero variable-frequency power.The magnetic saturation of induction machines provide useful magnetic torque while over saturation will result in stator current distortion and accordingly harmonic components.The harmonic current from ma-chines makes negative effect on aircraft distribution power system.A induction machine model , supplied with 115 V/600 Hz, was used for FEA approach to calculate three different saturation current due to saturat-ed teeth, yoke and air gap respectively.By analyzing the flux density of air gap , teeth and yoke, calculating current harmonics with Fourier decomposition , the relation between current harmonic and saturation was built.The current harmonics were compared among three saturation situations.The conclusion suggested the design way to limit high-order current harmonic components.

  15. Mechanical design of walking machines.

    Science.gov (United States)

    Arikawa, Keisuke; Hirose, Shigeo

    2007-01-15

    The performance of existing actuators, such as electric motors, is very limited, be it power-weight ratio or energy efficiency. In this paper, we discuss the method to design a practical walking machine under this severe constraint with focus on two concepts, the gravitationally decoupled actuation (GDA) and the coupled drive. The GDA decouples the driving system against the gravitational field to suppress generation of negative power and improve energy efficiency. On the other hand, the coupled drive couples the driving system to distribute the output power equally among actuators and maximize the utilization of installed actuator power. First, we depict the GDA and coupled drive in detail. Then, we present actual machines, TITAN-III and VIII, quadruped walking machines designed on the basis of the GDA, and NINJA-I and II, quadruped wall walking machines designed on the basis of the coupled drive. Finally, we discuss walking machines that travel on three-dimensional terrain (3D terrain), which includes the ground, walls and ceiling. Then, we demonstrate with computer simulation that we can selectively leverage GDA and coupled drive by walking posture control.

  16. Stacked Extreme Learning Machines.

    Science.gov (United States)

    Zhou, Hongming; Huang, Guang-Bin; Lin, Zhiping; Wang, Han; Soh, Yeng Chai

    2015-09-01

    Extreme learning machine (ELM) has recently attracted many researchers' interest due to its very fast learning speed, good generalization ability, and ease of implementation. It provides a unified solution that can be used directly to solve regression, binary, and multiclass classification problems. In this paper, we propose a stacked ELMs (S-ELMs) that is specially designed for solving large and complex data problems. The S-ELMs divides a single large ELM network into multiple stacked small ELMs which are serially connected. The S-ELMs can approximate a very large ELM network with small memory requirement. To further improve the testing accuracy on big data problems, the ELM autoencoder can be implemented during each iteration of the S-ELMs algorithm. The simulation results show that the S-ELMs even with random hidden nodes can achieve similar testing accuracy to support vector machine (SVM) while having low memory requirements. With the help of ELM autoencoder, the S-ELMs can achieve much better testing accuracy than SVM and slightly better accuracy than deep belief network (DBN) with much faster training speed.

  17. 基于 ADAMS 机枪射击稳定性动力学仿真分析%Dynamic Simulation Analysis on Firing Stability of Machine Gun Based on ADAMS

    Institute of Scientific and Technical Information of China (English)

    黄晓; 金永灿; 赵东艳; 廖振强; 张茂文

    2016-01-01

    针对大口径机枪射击稳定性低的问题,提出一种利用膛内火药气体能量来减小枪口跳动的稳定控制装置;鉴于枪管在稳定力作用下会发生变形,采用一种支架装置来加强枪管的刚度;基于刚柔糅合、多柔体动力学理论,以ADAMS、Matlab 软件为平台,对改进后的机枪进行仿真,枪口跳动的最大位移值下降了46%,脚架振动的最大位移值下降了41%,射击稳定性得到明显提高。%Aiming at the problem of low firing stability of large caliber machine gun,a stability control de-vice using the energy of the propellant gas was proposed to reduce the jump of the muzzle.Considering the deformation of the barrel under the force of stability control device,a bracket device was applied to im-prove stiffness.The machine gun that has been changed was simulated to verify the firing stability of ma-chine gun by using ADAMS and Matlab software based on rigid-flexible coupling and mufti-degree flexible-body dynamics theory.The maximum displacement value of the muzzle is decreased by 46%.The maxi-mum displacement of tripod vibration is decreased by 41%,and the firing stability improves a lot.

  18. Improved Design and Application of Three Dimensional Simulation of Corn Peeling Machine Parts%玉米剥皮机部件改进设计及三维仿真应用

    Institute of Scientific and Technical Information of China (English)

    李世豪; 齐应杰

    2017-01-01

    in the north of China, the climate is dry, which is suitable for the cultivation of maize, wheat and other semi dry crops. Corn planting and harvesting are simple and easy, the only more difficult to expand the work is the peeling. Corn peeling machine appears to greatly improve the efficiency of corn peeling. The maize peeling and there are still some drawbacks lead to poor efficiency of peeling, to further enhance the work efficiency of the machine, the need to improve the key parts of corn peeling machine, the corn husker components improved analysis, and develop a three-dimensional simulation.%我国北方气候干燥,较适宜种植玉米、小麦等半干旱性农作物。玉米种植及收割均简单易行,唯一较难展开的工作是剥皮工作,而玉米剥皮机的出现极大地提高了玉米剥皮效率。当前,玉米剥皮机仍旧存在一些弊端导致剥皮效率不佳,为进一步提升机器工作效率,需对玉米剥皮机关键部件进行改进。因此,对玉米剥皮机部件改进进行了分析,并展开了三维仿真。

  19. 机器视觉辅助的插头锥套式无人机自主空中加油仿真%Machine Vision Aided Simulation of Probe and Drogue Unmanned Aerial Vehicle Autonomous Aerial Refueling

    Institute of Scientific and Technical Information of China (English)

    王旭峰; 董新民; 孔星炜

    2013-01-01

    In order to precisely obtain the relative pose between probe and drogue during unmanned aerial vehicle (UAV) autonomous aerial refueling docking,a machine vision aided simulation scheme of probe-drogue UAV autonomous aerial refueling is proposed.Based on the machine vision,the recognition and tracking algorithm of refueling drogue is investigated.The relative pose between UAV and refueling drogue is estimated by using of Kalman filter algorithm.Experiment results show that the machine vision aided image processing algorithm can recognize and track refueling drogue precisely and the convergence of relative pose errors estimated by the filter algorithm is proved,fulfilling the demand of probe-drogue UAV autonomous aerial refueling.%为准确获取无人机自主空中加油对接阶段受油插头与加油锥套的相对位姿信息,提出一种机器视觉辅助的插头锥套式无人机自主空中加油方案.研究了机器视觉识别跟踪加油锥套的算法,利用卡尔曼滤波算法估计无人机与加油锥套的相对位姿.实验结果表明:机器视觉图像处理算法可精确识别跟踪加油锥套,滤波器估计的相对位姿误差收敛速度较快,满足插头锥套式无人机自主空中加油的需要.

  20. 模型驱动的复杂人机系统过程建模仿真方法%Model driven process modeling and simulation of complex man-machine systems

    Institute of Scientific and Technical Information of China (English)

    雷永林; 朱一凡; 谭跃进; 杨峰; 姚剑

    2016-01-01

    Complex man-machine systems (CMMS),as one of the most challenging areas in the field of sys-tems engineering,encompass complex technological machine behavior,cognitive decision-making behavior,and collaborative man-machine interaction behavior.In many cases,modeling and simulation (M&S)is the only via-ble approach to analyze the performance and effectiveness of CMMS.Various behavior and process modeling and representation methods applied to CMMS are briefed.Taking complex systems and their engagement-level com-bating as an representative example of CMMS,a behavior and process modeling framework featured with a physical-cognitive-structural separation is proposed based on the model driven development (MDD)paradigm.A set of modeling technologies including multiple formalism modeling and domain-specific modeling are employed to better design the simulation models of CMMS behavior and process.The proposed model driven modeling methodology is also applicable to the behavior and process modeling and simulation of other CMMS.%复杂人机系统涉及复杂的技术系统过程、认知决策过程以及人机协同过程,是当前系统工程研究最具挑战的领域之一。建模仿真在很多情况下是分析复杂人机系统过程性能效能的唯一可行选择。分析了复杂人机系统过程建模以及系统仿真模型表示的主要方法。结合平台级作战过程建模应用问题,给出了一种物理域、认知域、模型框架三分的复杂人机系统过程建模框架。在模型驱动方法的指导下,综合运用多方法建模、领域特定建模等方法讨论了复杂人机系统过程仿真模型设计问题。对其他领域的复杂人机系统过程建模仿真问题研究具有示范意义。

  1. Machine tool structures

    CERN Document Server

    Koenigsberger, F

    1970-01-01

    Machine Tool Structures, Volume 1 deals with fundamental theories and calculation methods for machine tool structures. Experimental investigations into stiffness are discussed, along with the application of the results to the design of machine tool structures. Topics covered range from static and dynamic stiffness to chatter in metal cutting, stability in machine tools, and deformations of machine tool structures. This volume is divided into three sections and opens with a discussion on stiffness specifications and the effect of stiffness on the behavior of the machine under forced vibration c

  2. Avaliação "in loco" das perdas de protensão de cordoalhas engraxadas em lajes planas

    Directory of Open Access Journals (Sweden)

    S. J. Soares

    Full Text Available Este trabalho apresenta os resultados de um estudo sobre as perdas de protensão, medidas "in loco", de cordoalhas engraxadas em lajes planas. Essas lajes planas, com 17 centímetros de espessura e 350 m2 de área, fazem parte de um edifício para fins hoteleiros de 16 pavimentos. As forças de protensão foram medidas por células de carga colocadas nas proximidades da ancoragem ativa e da ancoragem passiva. As medidas de forças foram feitas desde a protensão até idades de 170 dias após esse instante. Os resultados revelam um coeficiente de atrito μ igual a 0,0528 bastante próximo ao valor apresentado pela norma brasileira NBR 6118: 0,05. Nas perdas pela acomodação da ancoragem os valores apurados foram bastante similares e em termos médios, essa perda correspondeu a 5,17% da força inicial de protensão. Os valores de força medidos mostram também que a perda de tensão na cordoalha, próximo à ancoragem passiva, é menor em relação à perda na ancoragem ativa. Até a idade de 170 dias, verificou-se uma perda média de 14% da força inicial de protensão.

  3. The use of scintimammography for detecting the recurrence of loco-regional breast cancer: histopathologically proven results.

    Science.gov (United States)

    Bongers, Vivian; Perre, Cornelis; de Hooge, Pieter

    2004-02-01

    99mTc tetrofosmin scintimammography has been shown to be an accurate diagnostic test in patients with a symptomatic breast lesion and for whom a non-diagnostic mammogram has been obtained. Since a physical examination and conventional imaging modalities have their limitations in the detection of recurrent breast cancer, and survival is related to the extent of recurrent disease, complementary imaging modalities are warranted. To evaluate the role of 99mTc tetrofosmin scintimammography in detecting the recurrence of loco-regional breast cancer. Fifty-four patients underwent 55 scintimammography studies because either there were clinical indications of breast metastases, or there was a recurrence of metastases in the chest wall, and/or an evaluation of axillary, parasternal, supraclavicular and/or infraclavicular lymph node metastases was required. Planar breast imaging was performed 10 min after intravenous injection of 700 MBq 99mTc tetrofosmin. 99mTc tetrofosmin scintimammography was diagnostic in 50 of the 55 studies. An unknown lung metastasis was detected in one patient, and an unknown bone metastasis of the sternum was detected in another. Tumour involvement remained undetected in one neck node metastasis. Three patients had false positive scintimammography results, with 99mTc tetrofosmin uptake in an axillary, infraclavicular and parasternal lymph node, respectively. A fourth patient showed 99mTc tetrofosmin uptake in the scar, which appeared to be an inflammatory lesion, proven by a histopathological biopsy and 1 year clinical follow-up. 99mTc tetrofosmin scintimammography accurately detected 100% of the local recurrences independently of the extent of the preceding surgical intervention. The sensitivity and specificity of the technique for the detection of regional recurrent disease were 93% and 90%, respectively. These results are substantially higher than those of other imaging modalities.

  4. The effect of loco-regional anaesthesia on motor activity induced by direct stimulation of the sciatic nerve in dogs.

    Science.gov (United States)

    Murdoch, A P; Michou, J N

    2016-03-01

    A prospective, randomised, blinded, case-controlled clinical study was designed using client-owned dogs undergoing unilateral pelvic limb orthopaedic surgery, to determine the effect on induced motor activity by electrical stimulation of the sciatic nerve distal to the site of local anaesthetic administration. Dogs were administered 0.5% bupivacaine either extradurally or via a femoral and transgluteal sciatic electrolocation-guided nerve block prior to pelvic limb surgery. Motor response to electrical stimulation of branches of the sciatic nerve was tested and the minimum current required to induce muscle twitch was recorded prior to bupivacaine administration. Provided sensory blockade had been deemed successful intraoperatively, testing was repeated postoperatively, with each dog acting as its own control. Paired t-tests were performed to compare pre- and postoperative minimum currents. Eleven dogs administered extradural and 11 dogs administered femoral and sciatic perineural bupivacaine were eligible for post-operative testing. All dogs displayed normal motor response to electrical stimulation of the sciatic nerve at both sites tested before and after bupivacaine administration. There was no significant difference in the minimum current required to induce muscle twitch between pre- and post-operative testing (P = 0.31 sciatic site, P = 0.36 peroneal site), nor between the two groups using different loco-regional anaesthetic techniques (minimum P = 0.13). This study shows that stimulation of the sciatic nerve distal to the site of bupivacaine administration induces motor activity, despite adequate sensory blockade. This is relevant in surgical cases where mechanical stimulation of the sciatic nerve might be expected and needs to be recognised to avoid postoperative neurapraxia.

  5. Cogging Torque Minimization in Transverse Flux Machines

    Energy Technology Data Exchange (ETDEWEB)

    Husain, Tausif; Hasan, Iftekhar; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2017-02-16

    This paper presents the design considerations in cogging torque minimization in two types of transverse flux machines. The machines have a double stator-single rotor configuration with flux concentrating ferrite magnets. One of the machines has pole windings across each leg of an E-Core stator. Another machine has quasi-U-shaped stator cores and a ring winding. The flux in the stator back iron is transverse in both machines. Different methods of cogging torque minimization are investigated. Key methods of cogging torque minimization are identified and used as design variables for optimization using a design of experiments (DOE) based on the Taguchi method. A three-level DOE is performed to reach an optimum solution with minimum simulations. Finite element analysis is used to study the different effects. Two prototypes are being fabricated for experimental verification.

  6. Machine Learning wins the Higgs Challenge

    CERN Multimedia

    Abha Eli Phoboo

    2014-01-01

    The winner of the four-month-long Higgs Machine Learning Challenge, launched on 12 May, is Gábor Melis from Hungary, followed closely by Tim Salimans from the Netherlands and Pierre Courtiol from France. The challenge explored the potential of advanced machine learning methods to improve the significance of the Higgs discovery.   Winners of the Higgs Machine Learning Challenge: Gábor Melis and Tim Salimans (top row), Tianqi Chen and Tong He (bottom row). Participants in the Higgs Machine Learning Challenge were tasked with developing an algorithm to improve the detection of Higgs boson signal events decaying into two tau particles in a sample of simulated ATLAS data* that contains few signal and a majority of non-Higgs boson “background” events. No knowledge of particle physics was required for the challenge but skills in machine learning - the training of computers to recognise patterns in data – were essential. The Challenge, hosted by Ka...

  7. Diagnosing the Local Land-Atmosphere Coupling (LoCo) in Models and Observations: A Study of Dry/Wet Extremes in the U. S. Southern Great Plains

    Science.gov (United States)

    Santanello, J. A.; Peters-Lidard, C. D.; Kumar, S.; Dong, X.; Kennedy, A. D.

    2010-12-01

    Land-atmosphere interactions play a critical role in determining the diurnal evolution of both planetary boundary layer (PBL) and land surface temperature and moisture states. The degree of coupling between the land surface and PBL in numerical weather prediction and climate models remains largely unexplored and undiagnosed due to the complex interactions and feedbacks present across a range of scales. Further, uncoupled systems or experiments (e.g., the Project for Intercomparison of Land Parameterization Schemes, PILPS) may lead to inaccurate water and energy cycle process understanding by neglecting feedback processes such as PBL-top entrainment. In this study, a framework for diagnosing local land-atmosphere coupling (LoCo) is presented using a coupled mesoscale model with a suite of PBL and land surface model (LSM) options along with observations during the summers of 2006/7 in the U.S. Southern Great Plains. Specifically, the Weather Research and Forecasting (WRF) model has been coupled to NASA's Land Information System (LIS), which provides a flexible and high-resolution representation and initialization of land surface physics and states. A range of diagnostics exploring the links and feedbacks between soil moisture and precipitation are examined for the dry/wet extremes of this region, along with the sensitivity of PBL-LSM coupling to perturbations in soil moisture. As such, this methodology provides a potential pathway to study factors controlling local land-atmosphere coupling (LoCo) using the LIS-WRF system, which is serving as a testbed for LoCo experiments to evaluate coupling diagnostics within the community.

  8. 无刷同步电机起动发电系统的发电仿真研究%Simulation of the Modeling of Starter/Generator Based on Brushless Synchronous Machines

    Institute of Scientific and Technical Information of China (English)

    张超; 李岩; 王冬梅

    2011-01-01

    This paper introduces a modeling method of Brushless Synchronous Machines' model. A starter/generator system is Based on the model. By analysing the Typical transition process (from no load to load and the load to the three -2phase output short circuit) ,we can prove the correctness and effectiveness of Matlab simulation model.%运用Matlab中的PSB模块库和Simu link模块库,建立了无刷同步电机模型以及该模型的起动发电系统;通过对该系统发电状态下,由空载到负载和由空载到三相输出短路等典型过渡过程仿真分析,证明了所建Matlab仿真模型的正确性和有效性.

  9. 基于ADAMS的PRS- XY型混联机床机构运动学仿真分析%Kinematics Analysis and Simulation of the PRS- XY Hybrid Mechanism of the Machine Tool Based on ADAMS

    Institute of Scientific and Technical Information of China (English)

    朱海宁; 郭钢; 李传龙

    2011-01-01

    应用ADAMS软件对PRS - XY型混联机床机构进行运动学仿真分析,使用测量工具求得混联机构逆解,然后通过样条曲线和样条函数求得正解.借助于仿真软件快速准确地求出运动学正逆解,为实际的样机调试提供了有意义的借鉴.%Based on ADAMS, it simulates and analyzes the kinematics performance of the PRS- XY hybrid mechanism of the machine tool. It solves the kinematics functions of the PRS- XY mechanism with measuring tools and spline function, and proves that this solution model and the inverse solution model of kinematics of the hybrid mechanism are effective and rapid.

  10. Dose-Response Relationship between Radiation Dose and Loco-regional Control in Patients with Stage II-III Esophageal Cancer Treated with Definitive Chemoradiotherapy.

    Science.gov (United States)

    Kim, Hyun Ju; Suh, Yang-Gun; Lee, Yong Chan; Lee, Sang Kil; Shin, Sung Kwan; Cho, Byung Chul; Lee, Chang Geol

    2017-07-01

    The correlation between radiation dose and loco-regional control (LRC) was evaluated in patients with stage II-III esophageal cancer treated with definitive concurrent chemoradiotherapy (CRT). Medical records of 236 stage II-III esophageal cancer patients treated with definitive CRT at Yonsei Cancer Center between 1994 and 2013 were retrospectively reviewed. Among these, 120 received a radiation dose of 60 Gy) is associated with increased LRC, PFS, and OS in patients with stage II-III esophageal cancer treated with definitive CRT.

  11. Herança e ligação em locos de isoenzimas em Genipa americana L. Inheritance and linkage in isozymes loci of Genipa americana L.

    Directory of Open Access Journals (Sweden)

    Alexandre Magno SEBBENN

    2004-06-01

    Full Text Available A herança e a ligação foram estudadasem quatro locos polimórficos (6pghd-1, Pgi-2,Mdh-1 e Mdh-2 de três sistemas isoenzimáticos deGenipa americana, analisados por eletroforesehorizontal em gel de amido, usando tecidoscoletados de quinze progênies de polinização aberta,procedentes de Moji-Guaçu, Estado de São Paulo.Esses locos segregaram de dois a três alelos.A segregação nesses locos foi homogênea entreárvores. Contudo, existem desvios significativos dasegregação esperada 1:1 para algumas árvores emalguns locos. Desvios significativos da razão desegregação esperada 1:1 foram detectados noslocos Mdh-2 e 6pgdh-1. Não foram detectadasevidências de ligação entre nenhum dos pares delocos avaliados em G. americana e esses podemser utilizados sem restrição para estudos do sistemade reprodução, diversidade e estrutura genética depopulações da espécie.Inheritance and linkage for fourpolymorphic loci (6pghd-1, Pgi-2, Mdh-1 andMdh-2 from three enzyme systems in Genipaamericana were analyzed by horizontal starch gelelectrophoresis using tissues collected from fiftyopen-pollinated families in Moji-Guaçu, São PauloState. These allozyme loci have segregated fromtwo to four alleles per polymorphic locus. Genesegregation on those loci was homogeneous amongtrees. However, there were significant deviationsfrom the expected segregation ratios on some lociand some individual trees. In addition, Mdh-2 and6pgdh-1 loci have shown significant deviationsfrom the 1:1 expected segregation ratio. Linkagedisequilibrium evidences were not detected betweenany two pairs of loci from G. americana and thosecan be used with no restriction to study the matingsystem, genetic diversity, and genetic structure onthe species.

  12. Caracterização molecular do loco Red associado a resistência ao oídio da soja

    OpenAIRE

    Pereira,Alan Alves

    2015-01-01

    Diante da importância da cultura da soja e da severidade do oídio em causar danos, este estudo teve como principais objetivos avaliar linhagens endogâmicas recombinantes de soja para resistência a este patógeno e caracterizar molecularmente os genes de resistência localizados na região de mapeamento do loco Red, que confere resistência ao oídio em soja. Avaliações fenotípicas realizadas em 109 famílias derivadas do cruzamento entre o acesso BRI01-22106 (Resistente) e o acesso PI200487 (Suscet...

  13. Design of Demining Machines

    CERN Document Server

    Mikulic, Dinko

    2013-01-01

    In constant effort to eliminate mine danger, international mine action community has been developing safety, efficiency and cost-effectiveness of clearance methods. Demining machines have become necessary when conducting humanitarian demining where the mechanization of demining provides greater safety and productivity. Design of Demining Machines describes the development and testing of modern demining machines in humanitarian demining.   Relevant data for design of demining machines are included to explain the machinery implemented and some innovative and inspiring development solutions. Development technologies, companies and projects are discussed to provide a comprehensive estimate of the effects of various design factors and to proper selection of optimal parameters for designing the demining machines.   Covering the dynamic processes occurring in machine assemblies and their components to a broader understanding of demining machine as a whole, Design of Demining Machines is primarily tailored as a tex...

  14. Applied machining technology

    CERN Document Server

    Tschätsch, Heinz

    2010-01-01

    Machining and cutting technologies are still crucial for many manufacturing processes. This reference presents all important machining processes in a comprehensive and coherent way. It includes many examples of concrete calculations, problems and solutions.

  15. Machining with abrasives

    CERN Document Server

    Jackson, Mark J

    2011-01-01

    Abrasive machining is key to obtaining the desired geometry and surface quality in manufacturing. This book discusses the fundamentals and advances in the abrasive machining processes. It provides a complete overview of developing areas in the field.

  16. Women, Men, and Machines.

    Science.gov (United States)

    Form, William; McMillen, David Byron

    1983-01-01

    Data from the first national study of technological change show that proportionately more women than men operate machines, are more exposed to machines that have alienating effects, and suffer more from the negative effects of technological change. (Author/SSH)

  17. Machine medical ethics

    CERN Document Server

    Pontier, Matthijs

    2015-01-01

    The essays in this book, written by researchers from both humanities and sciences, describe various theoretical and experimental approaches to adding medical ethics to a machine in medical settings. Medical machines are in close proximity with human beings, and getting closer: with patients who are in vulnerable states of health, who have disabilities of various kinds, with the very young or very old, and with medical professionals. In such contexts, machines are undertaking important medical tasks that require emotional sensitivity, knowledge of medical codes, human dignity, and privacy. As machine technology advances, ethical concerns become more urgent: should medical machines be programmed to follow a code of medical ethics? What theory or theories should constrain medical machine conduct? What design features are required? Should machines share responsibility with humans for the ethical consequences of medical actions? How ought clinical relationships involving machines to be modeled? Is a capacity for e...

  18. Brain versus Machine Control.

    Directory of Open Access Journals (Sweden)

    Jose M Carmena

    2004-12-01

    Full Text Available Dr. Octopus, the villain of the movie "Spiderman 2", is a fusion of man and machine. Neuroscientist Jose Carmena examines the facts behind this fictional account of a brain- machine interface

  19. 注塑模数字化设计与加工仿真一体化技术研究%Research on Integrated Technique of Digital Design and Machining Simulation for Plastics Injection Mould

    Institute of Scientific and Technical Information of China (English)

    高征兵; 秦永法

    2011-01-01

    阐述一种注塑模数字化设计及加工过程仿真一体化技术.运用Pro/Engineer软件的通用功能模块及其模架设计专家(EMX)模块,进行塑件及其注塑模设计,并将模具中的成形零部件模型数据转换到MasterCAM中进行数控编程和加工仿真.以相机面壳注塑模设计与加工仿真为例,验证了该方法的可行性.该方法可以提高塑料注射模具的开发效率.%An integrated technique of plastics injection mould design and process simulation was elaborated. Plastics products and plastics injection mould were designed using the general function module of Pro/Engineer and its expert moldbase extension (EMX ) module. Then the model data were converted and imported into MasterCAM to program NC codes and to make machining simulation. As an application example, a camera's shell and its plastics injection mould were designed and simulated using the proposed method. The development efficiency of plastics injection mould can be improved using the method.

  20. 基于Pro/E和3DS Max的缝纫机原理仿真动画制作研究%Research on Simulation Animation Production of Sewing Machine Principle Based on Pro/E and 3DS Max

    Institute of Scientific and Technical Information of China (English)

    苗苗; 曹巨江

    2014-01-01

    Sewing principle simulation animation needs to meet higher requirements of the main functions models' geometry size's accuracy. Making and assembling the models of the sewing machine accurately by Pro/E, rendering and animating the three-dimensional models by 3DS Max,in order to finish the sewing principle simulation animation. This way gives full play to the advantages of Pro/E and 3DS Max soft-ware respectively, solves the problem of inaccurate of the parts' size and position by using 3DS Max alone, and provides a new idea for making mechanism animation simulation.%缝纫机原理仿真动画对缝纫机主要功能零件模型的几何尺寸准确度要求较高,利用Pro/E对缝纫机零部件进行精确建模和装配,将三维模型导入3DS Max中进行材质渲染和动画制作,完成缝纫机原理仿真动画。充分发挥Pro/E和3DS Max软件各自的优势,解决单独使用3DS Max软件在机构动画制作中零件的尺寸和装配不准确的问题,为机构仿真动画制作提供新思路。

  1. Análisis por medio de la simulación de un accionamiento con motor de reluctancia conmutada; Analysis by Means of Simulation of a Switched Reluctance Machines Drive

    Directory of Open Access Journals (Sweden)

    Javier Muñoz Álvarez

    2011-02-01

    Full Text Available Se presentan los fundamentos teóricos que modelan el comportamiento de los motores de reluctancia conmutaday sus accionamientos. Se exponen las características constructivas generales, las ecuaciones diferencialesque constituyen el modelo matemático del motor y se describen los bloques en Simulink utilizados para lasimulación. El sistema modular se valida comparando el comportamiento de las variables de salida con señalesobtenidas experimentalmente. Es empleado, además, para realizar diversos estudios sobre la instalación. Losresultados obtenidos en cada corrida son reflejados y se exponen las condiciones de operación y la explicaciónteórica de lo obtenido.  This paper presents the theoretical basis that models the behavior of The switched reluctance machines andtheir drives. The general characteristics, the differential equation system that constitutes the mathematicalmodel of the motor and the Simulink's blocks, which have been built for running the simulation, are outlined. Theresults of the simulation have been shown and compared with those obtained experimentally. The Simulinkmodel is used for studying the Switched Reluctance motor drive behavior under some operation conditions andtheoretical explanations for the simulation's results are given in every case.

  2. 3-D Simulation of the Temperature Field of Laser-Assisted Machining with FEM%激光辅助切削温度场的三维有限元仿真

    Institute of Scientific and Technical Information of China (English)

    王慧艺; 李从心; 阮雪榆

    2001-01-01

    激光加热的温度场受材料物性参数、工件几何形状、激光器功率、光斑形状及移动速度的影响.分析激光辅助立铣淬硬钢的工况,提出简化的计算模型,进而将非稳态传热方程化为稳态的传热控制方程.应用三维有限元法,对激光流动加热45#钢的温度场进行了仿真.经对比不同光斑形状、移动速度、光斑温度对温度场的影响,归纳了激光加热的特点,对激光辅助加工工艺参数的选择提出了建议.%Since the temperature field heated by moving laser is a huge gradient on space and time, it is not able to get a convincing result by experiments. However, it can be reproduced by 3-D simulation technology. Many factors affect the temperature field, like the material properties, geometry shape of a part, laser power, focus shape and moving rate. Based on laser-assisted milling of hardened steel, a simplified calculation model was suggested. Furthermore, the control equation of conduction was changed into static from dynamic. The temperature fields of 45# heated by moving laser was simulated with FEM and the different laser focus shapes, moving rates and temperatures were studied. The features of laser heating were concluded and the machining parameters of laser-assisted machining was suggested.

  3. Effect of focusing flow on stationary spot machining properties in elastic emission machining.

    Science.gov (United States)

    Takei, Yoshinori; Mimura, Hidekazu

    2013-05-16

    Ultraprecise optical elements are applied in advanced optical apparatus. Elastic emission machining (EEM) is one of the ultraprecision machining methods used to fabricate shapes with 0.1-nm accuracy. In this study, we proposed and experimentally tested the control of the shape of a stationary spot profile by introducing a focusing-flow state between the nozzle outlet and the workpiece surface in EEM. The simulation results indicate that the focusing-flow nozzle sharpens the distribution of the velocity on the workpiece surface. The results of machining experiments verified those of the simulation. The obtained stationary spot conditions will be useful for surface processing with a high spatial resolution.

  4. Tracking by Machine Learning Methods

    CERN Document Server

    Jofrehei, Arash

    2015-01-01

    Current track reconstructing methods start with two points and then for each layer loop through all possible hits to find proper hits to add to that track. Another idea would be to use this large number of already reconstructed events and/or simulated data and train a machine on this data to find tracks given hit pixels. Training time could be long but real time tracking is really fast Simulation might not be as realistic as real data but tacking has been done for that with 100 percent efficiency while by using real data we would probably be limited to current efficiency.

  5. BADMINTON TRAINING MACHINE WITH IMPACT MECHANISM

    OpenAIRE

    B.F. Yousif; KOK SOON YEH

    2011-01-01

    In the current work, a newly machine was designed and fabricated for badminton training purpose. In the designing process, CATIA software was used to design and simulate the machine components. The design was based on direct impact method to launch the shuttle using spring as the source of the impact. Hook’s law was used theoretically to determine the initial and the maximum lengths of the springs. The main feature of the machine is that can move in two axes (up and down, left and right). For...

  6. INTRODUCCIÓN DE ELEMENTOS DE MEMORIA EN EL MÉTODO SIMULATED ANNEALING PARA RESOLVER PROBLEMAS DE PROGRAMACIÓN MULTIOBJETIVO DE MÁQUINAS PARALELAS INTRODUCTION OF MEMORY ELEMENTS IN SIMULATED ANNEALING METHOD TO SOLVE MULTIOBJECTIVE PARALLEL MACHINE SCHEDULING PROBLEMS

    Directory of Open Access Journals (Sweden)

    Felipe Baesler

    2008-12-01

    Full Text Available El presente artículo introduce una variante de la metaheurística simulated annealing, para la resolución de problemas de optimización multiobjetivo. Este enfoque se demonina MultiObjective Simulated Annealing with Random Trajectory Search, MOSARTS. Esta técnica agrega al algoritmo Simulated Annealing elementos de memoria de corto y largo plazo para realizar una búsqueda que permita balancear el esfuerzo entre todos los objetivos involucrados en el problema. Los resultados obtenidos se compararon con otras tres metodologías en un problema real de programación de máquinas paralelas, compuesto por 24 trabajos y 2 máquinas idénticas. Este problema corresponde a un caso de estudio real de la industria regional del aserrío. En los experimentos realizados, MOSARTS se comportó de mejor manera que el resto de la herramientas de comparación, encontrando mejores soluciones en términos de dominancia y dispersión.This paper introduces a variant of the metaheuristic simulated annealing, oriented to solve multiobjective optimization problems. This technique is called MultiObjective Simulated Annealing with Random Trajectory Search (MOSARTS. This technique incorporates short an long term memory concepts to Simulated Annealing in order to balance the search effort among all the objectives involved in the problem. The algorithm was tested against three different techniques on a real life parallel machine scheduling problem, composed of 24 jobs and two identical machines. This problem represents a real life case study of the local sawmill industry. The results showed that MOSARTS behaved much better than the other methods utilized, because found better solutions in terms of dominance and frontier dispersion.

  7. An Intensional Concurrent Faithful Encoding of Turing Machines

    Directory of Open Access Journals (Sweden)

    Thomas Given-Wilson

    2014-10-01

    Full Text Available The benchmark for computation is typically given as Turing computability; the ability for a computation to be performed by a Turing Machine. Many languages exploit (indirect encodings of Turing Machines to demonstrate their ability to support arbitrary computation. However, these encodings are usually by simulating the entire Turing Machine within the language, or by encoding a language that does an encoding or simulation itself. This second category is typical for process calculi that show an encoding of lambda-calculus (often with restrictions that in turn simulates a Turing Machine. Such approaches lead to indirect encodings of Turing Machines that are complex, unclear, and only weakly equivalent after computation. This paper presents an approach to encoding Turing Machines into intensional process calculi that is faithful, reduction preserving, and structurally equivalent. The encoding is demonstrated in a simple asymmetric concurrent pattern calculus before generalised to simplify infinite terms, and to show encodings into Concurrent Pattern Calculus and Psi Calculi.

  8. Addressing uncertainty in atomistic machine learning.

    Science.gov (United States)

    Peterson, Andrew A; Christensen, Rune; Khorshidi, Alireza

    2017-05-10

    Machine-learning regression has been demonstrated to precisely emulate the potential energy and forces that are output from more expensive electronic-structure calculations. However, to predict new regions of the potential energy surface, an assessment must be made of the credibility of the predictions. In this perspective, we address the types of errors that might arise in atomistic machine learning, the unique aspects of atomistic simulations that make machine-learning challenging, and highlight how uncertainty analysis can be used to assess the validity of machine-learning predictions. We suggest this will allow researchers to more fully use machine learning for the routine acceleration of large, high-accuracy, or extended-time simulations. In our demonstrations, we use a bootstrap ensemble of neural network-based calculators, and show that the width of the ensemble can provide an estimate of the uncertainty when the width is comparable to that in the training data. Intriguingly, we also show that the uncertainty can be localized to specific atoms in the simulation, which may offer hints for the generation of training data to strategically improve the machine-learned representation.

  9. Identification of Mechanical parameters for Resistance Welding Machines

    DEFF Research Database (Denmark)

    Wu, Pei; Zhang, Wenqi; Bay, Niels

    2003-01-01

    Mechanical dynamic responses of resistance welding machine have a significant influence on weld quality and electrode service life, it must be considered when the real welding production is carried out or the welding process is simulated. The mathematical models for characterizing the mechanical...... to the complexities and differences of machine constructions. In this paper, a method of identifying the machine mechanical parameters based on the measured data is presented no matter how the machine construction and what types of machine are. The computations are implemented in MATLAB....

  10. Identification of Mechanical parameters for Resistance Welding Machines

    DEFF Research Database (Denmark)

    Wu, Pei; Zhang, Wenqi; Bay, Niels

    2003-01-01

    Mechanical dynamic responses of resistance welding machine have a significant influence on weld quality and electrode service life, it must be considered when the real welding production is carried out or the welding process is simulated. The mathematical models for characterizing the mechanical...... to the complexities and differences of machine constructions. In this paper, a method of identifying the machine mechanical parameters based on the measured data is presented no matter how the machine construction and what types of machine are. The computations are implemented in MATLAB....

  11. 基于数控加工的三维仿真系统设计%3D Simulation System Design Based on NC Machining

    Institute of Scientific and Technical Information of China (English)

    王秋鹏; 刘宏利

    2012-01-01

    Taking Windows system as the development platform, and with the auxiliary tool of OpenGL, the NC, CNC milling, drilling and processing of 3D simulation system were realized. The system was composed of NC program edit, real-ized NC program examination and interpretation, and also realized the simulation calculation and simulation display module, the specific features of NC code of the reverse simulation, and the actual turning, milling and drilling process is very close, and has strong practical significance and function.%以Windows系统为研发平台,辅助OpenGL工具,实现了数控车、数控铣、钻加工的三维仿真系统.该系统由数控程序编辑而成,建立了数控程序的检查和解释、仿真计算以及仿真显示等模块,具有数控代码反向仿真的特点,与实际的车削、铣削以及钻削加工过程十分贴近,具有较强的现实意义和作用.

  12. Asynchronized synchronous machines

    CERN Document Server

    Botvinnik, M M

    1964-01-01

    Asynchronized Synchronous Machines focuses on the theoretical research on asynchronized synchronous (AS) machines, which are "hybrids” of synchronous and induction machines that can operate with slip. Topics covered in this book include the initial equations; vector diagram of an AS machine; regulation in cases of deviation from the law of full compensation; parameters of the excitation system; and schematic diagram of an excitation regulator. The possible applications of AS machines and its calculations in certain cases are also discussed. This publication is beneficial for students and indiv

  13. Quantum machine learning.

    Science.gov (United States)

    Biamonte, Jacob; Wittek, Peter; Pancotti, Nicola; Rebentrost, Patrick; Wiebe, Nathan; Lloyd, Seth

    2017-09-13

    Fuelled by increasing computer power and algorithmic advances, machine learning techniques have become powerful tools for finding patterns in data. Quantum systems produce atypical patterns that classical systems are thought not to produce efficiently, so it is reasonable to postulate that quantum computers may outperform classical computers on machine learning tasks. The field of quantum machine learning explores how to devise and implement quantum software that could enable machine learning that is faster than that of classical computers. Recent work has produced quantum algorithms that could act as the building blocks of machine learning programs, but the hardware and software challenges are still considerable.

  14. Precision machine design

    CERN Document Server

    Slocum, Alexander H

    1992-01-01

    This book is a comprehensive engineering exploration of all the aspects of precision machine design - both component and system design considerations for precision machines. It addresses both theoretical analysis and practical implementation providing many real-world design case studies as well as numerous examples of existing components and their characteristics. Fast becoming a classic, this book includes examples of analysis techniques, along with the philosophy of the solution method. It explores the physics of errors in machines and how such knowledge can be used to build an error budget for a machine, how error budgets can be used to design more accurate machines.

  15. Postoperative radiotherapy appeared to improve the disease free survival rate of patients with extrahepatic bile duct cancer at high risk of loco-regional recurrence

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi Young; Kim, Jin Hee; Kim, Yong Hoon [Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of); Byun, Sang Jun [Dept. of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2016-12-15

    To investigate the outcomes of postoperative radiotherapy (RT), in patients with extrahepatic bile duct (EHBD) cancer by comparing the survival rate between patients undergoing surgery alone or surgery plus postoperative RT, and to identify the prognostic factors affecting survival. Between 2000 and 2013, 52 patients with EHBD cancer underwent surgical resection. Of these, 33 patients did not receive postoperative RT (group I), and 19 patients did (group II). R1 resection was significantly more frequent in group II. The median radiation dose was 5,040 cGy. The 3-year overall survival (OS) rate for group I and group II was 38% and 56%, respectively (p = 0.274). The 3-year disease free survival (DFS) rate for group I and group II was 20% and 31%, respectively (p = 0.049), and the 3-year loco-regional recurrence free survival (LRFS) rates were 19% and 58%, respectively (p = 0.002). Multivariate analyses showed that postoperative RT and lymphovascular invasion were independent prognostic factors for DFS and LRFS. Overall, 42 patients (80%) experienced treatment failure. Distant metastasis was the predominant pattern of failure in group II. Postoperative RT after surgical resection appeared to improve the loco-regional control and DFS rate. More effort is needed to reduce distant metastasis, the major pattern of failure, in patients who receive postoperative RT.

  16. Regulation of glia number in Drosophila by Rap/Fzr, an activator of the anaphase-promoting complex, and Loco, an RGS protein.

    Science.gov (United States)

    Kaplow, Margarita E; Korayem, Adam H; Venkatesh, Tadmiri R

    2008-04-01

    Glia mediate a vast array of cellular processes and are critical for nervous system development and function. Despite their immense importance in neurobiology, glia remain understudied and the molecular mechanisms that direct their differentiation are poorly understood. Rap/Fzr is the Drosophila homolog of the mammalian Cdh1, a regulatory subunit of the anaphase-promoting complex/cyclosome (APC/C). APC/C is an E3 ubiquitin ligase complex well characterized for its role in cell cycle progression. In this study, we have uncovered a novel cellular role for Rap/Fzr. Loss of rap/fzr function leads to a marked increase in the number of glia in the nervous system of third instar larvae. Conversely, ectopic expression of UAS-rap/fzr, driven by repo-GAL4, results in the drastic reduction of glia. Data from clonal analyses using the MARCM technique show that Rap/Fzr regulates the differentiation of surface glia in the developing larval nervous system. Our genetic and biochemical data further indicate that Rap/Fzr regulates glial differentiation through its interaction with Loco, a regulator of G-protein signaling (RGS) protein and a known effector of glia specification. We propose that Rap/Fzr targets Loco for ubiquitination, thereby regulating glial differentiation in the developing nervous system.

  17. Based on B/S structure of the tunnel boring machine operation simulation and fault diagnosis system%基于B/S架构的掘进机运行仿真与故障诊断系统研究

    Institute of Scientific and Technical Information of China (English)

    汤其建

    2015-01-01

    Yongcheng Vocational College developed to run the simulation and fault diagnosis system based on In‐ternet technology roadheader .The system uses advanced computer simulation technology virtual Tunneling sud‐den disposal and roadheader typical faults to troubleshoot .Teachers can set a variety of unexpected situations and failures on a server or superuser machine;Students can be performed on the brow ser side virtual training to deal with unexpected situations , troubleshooting , the status process and troubleshooting process , you can choose a variety of simulation tools and test equipment ,process automatic record .The system was applied to the teaching and training ,so that students can not only deepen the Tunneling relevant expertise to understand ,and can exercise their ability to handle emergencies and Diagnostics boring machine failure .The system is to improve student interest in learning and learning efficiency w hile reducing costs and time costs of teaching in schools and training institutions .%永城职业学院开发了基于网络技术的掘进机运行仿真与故障诊断系统。该系统利用先进的计算机虚拟仿真技术实现巷道掘进突发状况处置和掘进机典型故障诊断排除。教师可以在服务器或超级用户机上设置各种突发状况和故障;学生可以在浏览器端上进行虚拟实训,应对突发状况、排除故障,在状况处理和排除故障过程中,可选用各种仿真工具和检测仪器,过程自动记录。将该系统运用到教学和培训中,不但可以使学员加深对巷道掘进相关专业知识的理解,而且可以锻炼其处置突发状况和诊断掘进机故障的能力。该系统在提高学员学习兴趣和学习效率的同时,还能降低学校和培训机构的教学成本和时间成本。

  18. Ti-6Al-4V合金的修正本构模型及其有限元仿真%An Improved Constitutive Model and Finite Element Simulation for Machining Ti-6Al-4V Alloy

    Institute of Scientific and Technical Information of China (English)

    刘丽娟; 吕明; 武文革

    2013-01-01

    Johnson-Cook (J-C) material constitutive model is inaccurate for machining simulation of titanium alloy with high temperature and heavy impact.In this study,a modified constitutive model of Ti-6Al-4V alloy based on recrystallization was established considering the phenomenon of stress decline during machining.High-temperature SHPB (Split Hopkinson Pressure Bar) test was conducted to determine the true flow stress-strain relationship of Ti-6Al-4V alloy.With the SHPB test data,the modified constitutive model was developed by the variable separation method.The flow stress decreased significantly at the temperatures higher than the recrystallization temperature in the modified constitutive model,showing a good agreement with experimental results.A subroutine was then coded and embedded in the finite element simulation software AdvantEdge FEM with the return mapping stress integration algorithm.Finite element simulations for both J-C constitutive model and the modified constitutive model were performed.The result shows that the simulated stress decreases in J-C model and the modified model at 850℃ by 11% and 46.7%,respectively,indicating the modified constitutive model is more suitable for the condition of high temperature and heavy impact in machining titanium alloy.%为解决高温高压环境下Johnson-Cook(J-C)本构模型不再适用于Ti-6Al-4V合金切削有限元仿真的问题,建立了基于重结晶的修正J-C本构模型,它可以体现出高速切削Ti-6A1-4V合金时的应力回落现象.首先,利用霍普金森压杆试验测得了Ti-6A1-4V的应力-应变数据,利用变量分离法拟合出修正J-C本构模型,该模型可以反映材料发生相变时应力-应变曲线的变化趋势,并能很好地逼近压杆试验数据曲线.然后,以AdvantEdge FEM有限元软件为平台,采用回退映射应力积分算法编写子程序,将该修正本构模型和J-C本构模型导入有限元系统,并对这2种本构模型进行有限元仿真.仿

  19. Vectorial Formalism of Polyphase Synchronous Machine With Permanents Magnets

    Directory of Open Access Journals (Sweden)

    Nacéra Bachir Bouiadjra

    2013-04-01

    Full Text Available This paper presents a mathematical model that transforms the real machine to fictitious machines and our goal is to simulate these and see the behavior of these machines in load. The polyphase machines are developed mainly in the field of variable speed drives of high power because increasing the number of phases on the one hand allows to reduce the dimensions of the components in power modulators energy and secondly to improve the operating safety. By a vector approach (vector space, it is possible to find a set of single-phase machine and / or two-phase fictitious equivalent to polyphase synchronous machine. These fictitious machines are coupled electrically and mechanically but decoupled magnetically. This approach leads to introduce the concept of the equivalent machine (multimachine multiconverter system MMS which aims to analyze systems composed of multiple machines (or multiple converters in electric drives. A first classification multimachine multiconverter system follows naturally from MMS formalism. We present an example of a pentaphase (polyphase synchronous machine for a simulation and study the behavior of the machine load

  20. Perspex machine: VII. The universal perspex machine

    Science.gov (United States)

    Anderson, James A. D. W.

    2006-01-01

    The perspex machine arose from the unification of projective geometry with the Turing machine. It uses a total arithmetic, called transreal arithmetic, that contains real arithmetic and allows division by zero. Transreal arithmetic is redefined here. The new arithmetic has both a positive and a negative infinity which lie at the extremes of the number line, and a number nullity that lies off the number line. We prove that nullity, 0/0, is a number. Hence a number may have one of four signs: negative, zero, positive, or nullity. It is, therefore, impossible to encode the sign of a number in one bit, as floating-point arithmetic attempts to do, resulting in the difficulty of having both positive and negative zeros and NaNs. Transrational arithmetic is consistent with Cantor arithmetic. In an extension to real arithmetic, the product of zero, an infinity, or nullity with its reciprocal is nullity, not unity. This avoids the usual contradictions that follow from allowing division by zero. Transreal arithmetic has a fixed algebraic structure and does not admit options as IEEE, floating-point arithmetic does. Most significantly, nullity has a simple semantics that is related to zero. Zero means "no value" and nullity means "no information." We argue that nullity is as useful to a manufactured computer as zero is to a human computer. The perspex machine is intended to offer one solution to the mind-body problem by showing how the computable aspects of mind and, perhaps, the whole of mind relates to the geometrical aspects of body and, perhaps, the whole of body. We review some of Turing's writings and show that he held the view that his machine has spatial properties. In particular, that it has the property of being a 7D lattice of compact spaces. Thus, we read Turing as believing that his machine relates computation to geometrical bodies. We simplify the perspex machine by substituting an augmented Euclidean geometry for projective geometry. This leads to a general

  1. Kinematic modelling of a 3-axis NC machine tool in linear and circular interpolation

    CERN Document Server

    Pessoles, Xavier; Rubio, Walter; 10.1007/s00170-009-2236-z

    2010-01-01

    Machining time is a major performance criterion when it comes to high-speed machining. CAM software can help in estimating that time for a given strategy. But in practice, CAM-programmed feed rates are rarely achieved, especially where complex surface finishing is concerned. This means that machining time forecasts are often more than one step removed from reality. The reason behind this is that CAM routines do not take either the dynamic performances of the machines or their specific machining tolerances into account. The present article seeks to improve simulation of high-speed NC machine dynamic behaviour and machining time prediction, offering two models. The first contributes through enhanced simulation of three-axis paths in linear and circular interpolation, taking high-speed machine accelerations and jerks into account. The second model allows transition passages between blocks to be integrated in the simulation by adding in a polynomial transition path that caters for the true machining environment t...

  2. Simulation of machining composites with small-angle drills%小角度螺旋槽钻头加工复合材料的模拟研究

    Institute of Scientific and Technical Information of China (English)

    王明海; 孙国强; 孙越

    2012-01-01

    According to the problems of burrs and avulsion which are often observed in drilling CFRP laminates. A new drill with 10°helix angle and 83°point angle which is named small-angle drill is first put forward to be used in finite element analysis to research the effect of drill geometry on machining quality of drilling composite materials. The effects of spindle speed, feed rate and drill geometry on thrust force caused in the machining simulation process are given. Thrust forces and machining qualities of small-angle drill and twist drill are contrasted. By comparing the results and observing the hole quality drilled by different tools, it is reported that the thrust force is influenced more by spindle speed than feed rate and the higher spindle speed and lower feed rate are beneficial to reduce the thrust force, small-angle drill is more suitable for drilling CFRP.%针对碳纤维复合材料制孔时易产生毛刺、撕裂、分层等难题,首次提出了一种螺旋角为10°且顶角为83°的小角度螺旋槽钻头加工碳纤维复合材料的方法,并进行了钻削过程的有限元模拟分析.给出了主轴转速、进给速度、钻头几何角度等对加工过程中产生的钻削轴向力的影响,对比分析了两种钻头加工碳纤维复合材料的轴向力和加工出口质量.结果表明:复合材料的钻削轴向力受主轴转速的影响大于进给速度,并随主轴转速的增大而减小,随进给速度的增大而增大;同时,小角度螺旋槽钻头加工碳纤维复合材料时产生的轴向力小于麻花钻,破坏区域小,加工质量好,更适合碳纤维复合材料的制孔加工.

  3. 内锥面刃磨机实现麻花钻螺旋面刃磨的研究与仿真%Research and simulation to realize helicoid grinding of twist drill with inner cone grinding machine

    Institute of Scientific and Technical Information of China (English)

    戴俊平; 郭辉; 关文魁; 卜睿

    2012-01-01

    According to the working principle of inner cone grinding machine, the differential of plate units is increased to replace the traditional variable lead.And two step motors are applied to drive respectively ball screw spindle and nut relative rotation and synthetize any thread pitch.Thus the method to achieve adjustable lead helicoid grinding is put forward as well as the method for grinding the helicoid within inner cone grinding machine,and then the formula of relief angle and oblique of chisel edge after grinding is derived.The author designs a virtual prototype of inner cone grinding machine with the Pro/E Software to realize helicoid grinding by motion simulation in its mechanism,which results verify that the mechanism after improving can realize the helicoid grinding.The mechanism is conducive to the realization of digital control of mechanical grinding.%根据内锥面刃磨机的工作原理,增加双层拖板的差动来代替传统的变导程,利用两步进电机分别带动丝杠主轴与螺母相对转动,合成任意螺距.实现导程可调的新螺旋面刃磨的方法,由此实现了在内锥面刃磨机中进行螺旋面刃磨的方法,并推导了刃磨后后角与横刃斜角的公式.然后基于Pro/E软件设计了机构的虚拟样机,并以双层拖板的分析为例对机构实现螺旋面刃磨而进行运动仿真,结果验证了改进后的机构可以实现螺旋面刃磨.此机构有利于实现数字化控制的机械刃磨.

  4. 基于Abaqus/explicit的钛合金高速切削切削力模拟研究%Simulation Study on Cutting Force During High Speed Machining Titanium Alloy Based on Abaqus/explicit

    Institute of Scientific and Technical Information of China (English)

    芮执元; 李川平; 郭俊锋; 冯瑞成

    2011-01-01

    The aim of this research was to investigate cutting force during high speed machining titanium alloy. Johnson- Cook materials model and fracture criterion of commercial finite element software Abaqus was used to simulate high speed machining Ti6Al4V. It was Analyzed that The influence of the cutting parameters (including feed rate, cutting depth, cutting speed) on the cutting forces. The results shown that cutting force, feed force, specific cutting force and specific feed force reduced with increases in cutting speed, cutting force, feed force increased and specific cutting force, specific feed force reduced with increases in feed rate.%针对高速切削钛合金时切削力的问题,利用有限元分析软件Abaqus的Johnson-Cook材料模型及Johnson-Cook断裂准则,对钛合金高速切削切削力进行了仿真研究,分析钛合金高速切削加工过程中各切削参数(包括进给量、切削深度和切削速度)对切削力的影响.结果表明,切削力、进给力、单位面积切削力和单位面积进给力都随速度的增大而减小;但随着进给速度的增大,切削力和进给力都增大,而单位面积的切削力和进给力都减小.

  5. Programming and machining of the base parts based on NC simulation system%基于数控仿真系统的底座零件编程与加工

    Institute of Scientific and Technical Information of China (English)

    金江

    2012-01-01

    With the development of society and economy, as well as the actual production of the strong demand, the traditional manufacturing has undergone a fundamental change, with numerical control technology based on modern manufacturing technology to occupy an important position. This article through the base parts of the structure analysis, using Auto - CAD software to the base part drawing design, and process analysis, determine the machining process. Finally, according to the parameters, using Mastercam / Mill9 on parts of the program for entity authentication, automatic processing program for processing export. The auto- matic processing program for machining simulation.%随着社会经济的发展和生产实际的强烈需求,传统的制造方式已发生了根本性的变革,以数控技术为主的现代制造技术占据了重要地位.文章通过底座零件的结构分析,利用Auto—CAD软件进行底座零件图设计,而后进行工艺分析,确定零件的加工工艺;之后根据工艺参数,运用Mastercam\Mi119对零件程序进行实体验证,后处理导出自动加工程序;再对自动加工程序进行仿真加工.

  6. Simulation

    DEFF Research Database (Denmark)

    Gould, Derek A; Chalmers, Nicholas; Johnson, Sheena J

    2012-01-01

    Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable p...... performance assessments. Human factors research is central to simulator model development that is relevant to real-world imaging-guided interventional tasks and to the credentialing programs in which it would be used.......Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable...

  7. Simulation

    CERN Document Server

    Ross, Sheldon

    2006-01-01

    Ross's Simulation, Fourth Edition introduces aspiring and practicing actuaries, engineers, computer scientists and others to the practical aspects of constructing computerized simulation studies to analyze and interpret real phenomena. Readers learn to apply results of these analyses to problems in a wide variety of fields to obtain effective, accurate solutions and make predictions about future outcomes. This text explains how a computer can be used to generate random numbers, and how to use these random numbers to generate the behavior of a stochastic model over time. It presents the statist

  8. Metal release from coffee machines and electric kettles.

    Science.gov (United States)

    Müller, Frederic D; Hackethal, Christin; Schmidt, Roman; Kappenstein, Oliver; Pfaff, Karla; Luch, Andreas

    2015-01-01

    The release of elemental ions from 8 coffee machines and 11 electric kettles into food simulants was investigated. Three different types of coffee machines were tested: portafilter espresso machines, pod machines and capsule machines. All machines were tested subsequently on 3 days before and on 3 days after decalcification. Decalcification of the machines was performed with agents according to procedures as specified in the respective manufacturer's manuals. The electric kettles showed only a low release of the elements analysed. For the coffee machines decreasing concentrations of elements were found from the first to the last sample taken in the course of 1 day. Metal release on consecutive days showed a decreasing trend as well. After decalcification a large increase in the amounts of elements released was encountered. In addition, the different machine types investigated clearly differed in their extent of element release. By far the highest leaching, both quantitatively and qualitatively, was found for the portafilter machines. With these products releases of Pb, Ni, Mn, Cr and Zn were in the range and beyond the release limits as proposed by the Council of Europe. Therefore, a careful rinsing routine, especially after decalcification, is recommended for these machines. The comparably lower extent of release of one particular portafilter machine demonstrates that metal release at levels above the threshold that triggers health concerns are technically avoidable.

  9. Construção e aplicação de um minissensor de filme de bismuto utilizando materiais de baixo custo para determinações voltamétricas in loco

    Directory of Open Access Journals (Sweden)

    Luiz Carlos S. Figueiredo-Filho

    2012-01-01

    Full Text Available The construction of a low cost mini sensor containing a bismuth-film electrode (BiFE, as work electrode, a silver electrode as pseudo reference electrode, and copper as counter electrode is proposed. The application of this mini sensor using a low cost electrochemical cell for in loco voltammetric determinations of inorganic and organic analytes is also described.

  10. Isolated loco-regional recurrence of breast cancer is more common in young patients and following breast conserving therapy: Long-term results of European Organisation for Research and Treatment of Cancer studies

    NARCIS (Netherlands)

    de Bock, Truuske; van der Hage, J.A.; Putter, H.; Bonnema, J.; Bartelink, H.; van de Velde, C.J.

    2006-01-01

    The aim of this study was to evaluate prognostic factors for isolated loco-regional recurrence in patients treated for invasive stage I or H breast cancer. The study population comprised 3602 women who had undergone primary surgery for early stage breast cancer, who were enrolled in European Organis

  11. Linking white matter integrity loss to associated cortical regions using structural connectivity information in Alzheimer's disease and fronto-temporal dementia: the Loss in Connectivity (LoCo) score.

    Science.gov (United States)

    Kuceyeski, Amy; Zhang, Yu; Raj, Ashish

    2012-07-16

    It is well known that gray matter changes occur in neurodegenerative diseases like Alzheimer's (AD) and fronto-temporal dementia (FTD), and several studies have investigated their respective patterns of atrophy progression. Recent work, however, has revealed that diffusion MRI that is able to detect white matter integrity changes may be an earlier or more sensitive biomarker in both diseases. However, studies that examine white matter changes only are limited in that they do not provide the functional specificity of GM region-based analysis. In this study, we develop a new metric called the Loss in Connectivity (LoCo) score that gives the amount of structural network disruption incurred by a gray matter region for a particular pattern of white matter integrity loss. Leveraging the relative strengths of WM and GM markers, this metric links areas of WM integrity loss to their connected GM regions as a first step in understanding their functional implications. The LoCo score is calculated for three groups: 18AD, 18 FTD, and 19 age-matched normal controls. We show significant correlations of the LoCo with the respective atrophy patterns in AD (R=0.51, p=2.2 × 10(-9)) and FTD (R=0.49, p=2.5 × 10(-8)) for a standard 116 region gray matter atlas. In addition, we demonstrate that the LoCo outperforms a measure of gray matter atrophy when classifying individuals into AD, FTD, and normal groups.

  12. Isolated loco-regional recurrence of breast cancer is more common in young patients and following breast conserving therapy : Long-term results of European Organisation for Research and Treatment of Cancer studies

    NARCIS (Netherlands)

    de Bock, GH; van der Hage, JA; Putter, H; Bonnema, J; Bartelink, H; van de Velde, CJ

    2006-01-01

    The aim of this study was to evaluate prognostic factors for isolated loco-regional recurrence in patients treated for invasive stage I or H breast cancer. The study population comprised 3602 women who had undergone primary surgery for early stage breast cancer, who were enrolled in European Organis

  13. Role of tumour-free margin distance for loco-regional control in vulvar cancer-a subset analysis of the Arbeitsgemeinschaft Gynakologische Onkologie CaRE-1 multicenter study

    NARCIS (Netherlands)

    Woelber, Linn; Griebel, Lis-Femke; Eulenburg, Christine; Sehouli, Jalid; Jueckstock, Julia; Hilpert, Felix; de Gregorio, Nikolaus; Hasenburg, Annette; Ignatov, Atanas; Hillemanns, Peter; Fuerst, Sophie; Strauss, Hans-Georg; Baumann, Klaus H.; Thiel, Falk C.; Mustea, Alexander; Meier, Werner; Harter, Philipp; Wimberger, Pauline; Hanker, Lars Christian; Schmalfeldt, Barbara; Canzler, Ulrich; Fehm, Tanja; Luyten, Alexander; Hellriegel, Martin; Kosse, Jens; Heiss, Christoph; Hantschmann, Peer; Mallmann, Peter; Tanner, Berno; Pfisterer, Jacobus; Richter, Barbara; Neuser, Petra; Mahner, Sven

    2016-01-01

    Aim of the study: A tumour-free pathological resection margin of >= 8 mm is considered state-of-the-art. Available evidence is based on heterogeneous cohorts. This study was designed to clarify the relevance of the resection margin for loco-regional control in vulvar cancer. Methods: AGO-CaRE-1 is a

  14. Herança genética e desequilíbrio de ligação em locos de isoenzimas em Esenbeckia leiocarpa. Genetic inheritance and linkage disequilibrium in isozymes loci of Esenbeckia leiocarpa.

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Sícole SEOANE

    2004-06-01

    Full Text Available Oito sistemas enzimáticos (EST, IDH, PGM, PGI, MDH, PER, 6PGDH e SKDH codificando nove locos foram investigados em Esenbeckia leiocarpa. Quatro sistemas isoenzimáticos foram monomórficos (IDH, PGM, 6PGDH e SKDH e quatro polimórficos (EST, PGI, MDH e PER. A herança mendeliana foi confirmada para quatro locos, pelo teste de ajuste dos padrões de segregação observados em relação à razão de segregação esperada 1:1, em progênies de árvores heterozigotas. O desequilíbrio de ligação foi examinado para dez pares de locos. Apenas um simples par de locos parece estar em desequilíbrio de ligação, Est-1:Prx-1.Eight enzymes systems (EST, IDH, PGM, PGI, MDH, PER, 6PGDH and SKDH coding for nine loci were investigate in Esenbeckia leiocarpa. Four allozyme systems were monomorphic (IDH, PGM, 6PGDH and SKDH and four polymorphic (EST, PGI, MDH and PER. Mendelian inheritance was confirmed for four loci by testing the fit of band-pattern to 1:1 expected segregation ratio in progeny from heterozygous trees. Linkage disequilibrium was examined for ten pair of allozymes loci. A simple pair of loci appears to be in linkage disequilibrium, Est-1:Prx-1.

  15. Flow field simulation and establishment for mathematical models of flow area of spool valve with sloping U-shape notch machined by different methods

    Institute of Scientific and Technical Information of China (English)

    王兆强; 顾临怡; 冀宏; 陈家旺; 李林

    2014-01-01

    Precise function expression of the flow area for the sloping U-shape notch orifice versus the spool stroke was derived. The computational fluid dynamics was used to analyze the flow features of the sloping U-shape notch on the spool, such as mass flow rates, flow coefficients, efflux angles and steady state flow forces under different operating conditions. At last, the reliability of the mathematical model of the flow area for the sloping U-shape notch orifice on the spool was demonstrated by the comparison between the orifice area curve derived and the corresponding experimental data provided by the test. It is presented that the bottom arc of sloping U-shape notch (ABU) should not be omitted when it is required to accurately calculate the orifice area of ABU. Although the theoretical flow area of plain bottom sloping U-shape notch (PBU) is larger than that of ABU at the same opening, the simulated mass flow and experimental flow area of ABU are both larger than these of PBU at the same opening, while the simulated flow force of PBU is larger than that of ABU at the same opening. Therefore, it should be prior to adapt the ABU when designing the spool with proportional character.

  16. Study on Temperature Filed Simulation During Electro-discharge Machining of TiC/Ni Cermet%TiC/Ni金属陶瓷电火花加工温度场仿真研究

    Institute of Scientific and Technical Information of China (English)

    冯业瑞; 郭永丰; 李宗峰

    2016-01-01

    为深入研究TiC/Ni金属陶瓷电火花加工过程,进行了TiC/Ni金属陶瓷电火花加工单脉冲放电温度场仿真。建立了TiC/Ni金属陶瓷颗粒随机分布模型,运用ANSYS软件采用生死单元法对TiC/Ni金属陶瓷进行单脉冲温度场仿真研究,并对结果进行了实验验证。结果表明:TiC/Ni金属陶瓷颗粒随机分布模型适于TiC/Ni金属陶瓷电火花加工温度场仿真,且随着峰值电流及脉宽的增大,TiC/Ni金属陶瓷蚀除体积增加,表现为试验时材料蚀除率增加。%To study electro-discharge machining (EDM) process of TiC/Ni cermet ,the temperature field simulation of single pulse EDM of TiC/Ni cermet was carried out ,the randomly distribution model of TiC/Ni cermet particles was established. The single pulse temperature field was simulated using birth-death element method based on ANSYS software. Experimental results verify that the model is suitable for EDM temperature field simulation of TiC/Ni cermet. The results also show that with increase of peak current and pulse-on time ,due to increase of material removal rate ,material removal volume of TiC/Ni cermet increase.

  17. Addressing uncertainty in atomistic machine learning

    DEFF Research Database (Denmark)

    Peterson, Andrew A.; Christensen, Rune; Khorshidi, Alireza

    2017-01-01

    Machine-learning regression has been demonstrated to precisely emulate the potential energy and forces that are output from more expensive electronic-structure calculations. However, to predict new regions of the potential energy surface, an assessment must be made of the credibility of the predi......Machine-learning regression has been demonstrated to precisely emulate the potential energy and forces that are output from more expensive electronic-structure calculations. However, to predict new regions of the potential energy surface, an assessment must be made of the credibility...... of the predictions. In this perspective, we address the types of errors that might arise in atomistic machine learning, the unique aspects of atomistic simulations that make machine-learning challenging, and highlight how uncertainty analysis can be used to assess the validity of machine-learning predictions. We...... suggest this will allow researchers to more fully use machine learning for the routine acceleration of large, high-accuracy, or extended-time simulations. In our demonstrations, we use a bootstrap ensemble of neural network-based calculators, and show that the width of the ensemble can provide an estimate...

  18. Machinability of advanced materials

    CERN Document Server

    Davim, J Paulo

    2014-01-01

    Machinability of Advanced Materials addresses the level of difficulty involved in machining a material, or multiple materials, with the appropriate tooling and cutting parameters.  A variety of factors determine a material's machinability, including tool life rate, cutting forces and power consumption, surface integrity, limiting rate of metal removal, and chip shape. These topics, among others, and multiple examples comprise this research resource for engineering students, academics, and practitioners.

  19. Pattern recognition & machine learning

    CERN Document Server

    Anzai, Y

    1992-01-01

    This is the first text to provide a unified and self-contained introduction to visual pattern recognition and machine learning. It is useful as a general introduction to artifical intelligence and knowledge engineering, and no previous knowledge of pattern recognition or machine learning is necessary. Basic for various pattern recognition and machine learning methods. Translated from Japanese, the book also features chapter exercises, keywords, and summaries.

  20. Support vector machines applications

    CERN Document Server

    Guo, Guodong

    2014-01-01

    Support vector machines (SVM) have both a solid mathematical background and good performance in practical applications. This book focuses on the recent advances and applications of the SVM in different areas, such as image processing, medical practice, computer vision, pattern recognition, machine learning, applied statistics, business intelligence, and artificial intelligence. The aim of this book is to create a comprehensive source on support vector machine applications, especially some recent advances.

  1. Machining of titanium alloys

    CERN Document Server

    2014-01-01

    This book presents a collection of examples illustrating the resent research advances in the machining of titanium alloys. These materials have excellent strength and fracture toughness as well as low density and good corrosion resistance; however, machinability is still poor due to their low thermal conductivity and high chemical reactivity with cutting tool materials. This book presents solutions to enhance machinability in titanium-based alloys and serves as a useful reference to professionals and researchers in aerospace, automotive and biomedical fields.

  2. Characterisation of Dynamic Mechanical Properties of Resistance Welding Machines

    DEFF Research Database (Denmark)

    Wu, Pei; Zhang, Wenqi; Bay, Niels

    2005-01-01

    The dynamic mechanical properties of a resistance welding machine have significant influence on weld quality, which must be considered when simulating the welding process numerically. However, due to the complexity of the machine structure and the mutual coupling of components of the machine system...... characterizing the dynamic mechanical characteristics of resistance welding machines is suggested, and a test set-up is designed determining the basic, independent machine parameters required in the model. The model is verified by performing a series of mechanical tests as well as real projection welds......., it is very difficult to measure or calculate the basic, independent machine parameters required in a mathematical model of the machine dynamics, and no test method has so far been presented in literature, which can be applied directly in an industrial environment. In this paper, a mathematical model...

  3. Thermal models of electric machines with dynamic workloads

    Directory of Open Access Journals (Sweden)

    Christian Pohlandt

    2015-07-01

    Full Text Available Electric powertrains are increasingly used in off-highway machines because of easy controllability and excellent overall efficiency. The main goals are increasing the energy efficiency of the machine and the optimization of the work process. The thermal behaviour of electric machines with dynamic workloads applied to is a key design factor for electric powertrains in off-highway machines. This article introduces a methodology to model the thermal behaviour of electric machines. Using a noncausal modelling approach, an electric powertrain is analysed for dynamic workloads. Cause-effect relationships and reasons for increasing temperature are considered as well as various cooling techniques. The validation of the overall simulation model of the powertrain with measured field data workloads provides convincing results to evaluate numerous applications of electric machines in off-highway machines.

  4. Characterisation of Dynamic Mechanical Properties of Resistance Welding Machines

    DEFF Research Database (Denmark)

    Wu, Pei; Zhang, Wenqi; Bay, Niels

    2005-01-01

    The dynamic mechanical properties of a resistance welding machine have significant influence on weld quality, which must be considered when simulating the welding process numerically. However, due to the complexity of the machine structure and the mutual coupling of components of the machine system......, it is very difficult to measure or calculate the basic, independent machine parameters required in a mathematical model of the machine dynamics, and no test method has so far been presented in literature, which can be applied directly in an industrial environment. In this paper, a mathematical model...... characterizing the dynamic mechanical characteristics of resistance welding machines is suggested, and a test set-up is designed determining the basic, independent machine parameters required in the model. The model is verified by performing a series of mechanical tests as well as real projection welds....

  5. Sensorless Control of Permanent Magnet Synchronous Machines

    DEFF Research Database (Denmark)

    Matzen, Torben N.

    Permanent magnet machines, with either surface mounted or embedded magnets on the rotor, are becoming more common due to the key advantages of higher energy conversion efficiency and higher torque density compared to the classical induction machine. Besides energy efficiency the permanent magnet...... are dependent on the phase currents and rotor position. Based on the flux linkages the differential inductances are determined and used to establish the inductance saliency in terms of ratio and orientation. The orientation and its dependence on the current and rotor position are used to analyse the behaviour...... and establish the suitability of the machine for sensorless control using inductance saliency tracking methods. The same electromagnetic behaviour is used in the implementation of a dynamical simulation model of the machine useful for evaluation of sensorless control methods at the control design stage. Further...

  6. BADMINTON TRAINING MACHINE WITH IMPACT MECHANISM

    Directory of Open Access Journals (Sweden)

    B. F. YOUSIF

    2011-02-01

    Full Text Available In the current work, a newly machine was designed and fabricated for badminton training purpose. In the designing process, CATIA software was used to design and simulate the machine components. The design was based on direct impact method to launch the shuttle using spring as the source of the impact. Hook’s law was used theoretically to determine the initial and the maximum lengths of the springs. The main feature of the machine is that can move in two axes (up and down, left and right. For the control system, infra-red sensor and touch switch were adapted in microcontroller. The final product was locally fabricated and proved that the machine can operate properly.

  7. Python for probability, statistics, and machine learning

    CERN Document Server

    Unpingco, José

    2016-01-01

    This book covers the key ideas that link probability, statistics, and machine learning illustrated using Python modules in these areas. The entire text, including all the figures and numerical results, is reproducible using the Python codes and their associated Jupyter/IPython notebooks, which are provided as supplementary downloads. The author develops key intuitions in machine learning by working meaningful examples using multiple analytical methods and Python codes, thereby connecting theoretical concepts to concrete implementations. Modern Python modules like Pandas, Sympy, and Scikit-learn are applied to simulate and visualize important machine learning concepts like the bias/variance trade-off, cross-validation, and regularization. Many abstract mathematical ideas, such as convergence in probability theory, are developed and illustrated with numerical examples. This book is suitable for anyone with an undergraduate-level exposure to probability, statistics, or machine learning and with rudimentary knowl...

  8. 立式环模颗粒成型机压辊性能仿真分析%Performance simulation analysis of pressure roller in vertical pellets forming machine with circular mould

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    立式环模颗粒成型机是一种新型生物质燃料颗粒的生产设备,采用偏心轴压辊式结构,即压辊绕轴转动,与环模接触将物料挤出,压辊成为成型机稳定工作的关键影响因素之一。基于虚拟样机仿真技术,利用有限元分析软件对压辊组件进行静态结构仿真分析,得出在正向与侧向受载情况下,压辊所受最大等效应力小于材料本身许用应力,并且压辊的最大变形量远远小于其压辊的总体尺寸,压辊的强度与刚度可以得到保证,从而验证成型机压辊的结构性能合理性。%Vertical pellets forming machine with circular mould is a new kind of biomass pellets forming equip-ment,it uses eccentric shaft structure in pressure roller component. Biomass pellets squeezed from circular mould to make out pellets by contacted with roller,when the eccentric shaft rotates. In conclusion,it is one of key factor in forming machine,and influences its effective operation. Based on virtual prototyping simulation technology,it analyzes roller by the static structural simulation software. It concludes that the maximum equivalent stress of roller is less than its permissible stress,and the maximum deformation of roller is less than its the overall size in the case of the forward and lateral load. So the strength and stiffness of the roller can be guaranteed,and verify its structural rationality.

  9. Rotating electrical machines

    CERN Document Server

    Le Doeuff, René

    2013-01-01

    In this book a general matrix-based approach to modeling electrical machines is promulgated. The model uses instantaneous quantities for key variables and enables the user to easily take into account associations between rotating machines and static converters (such as in variable speed drives).   General equations of electromechanical energy conversion are established early in the treatment of the topic and then applied to synchronous, induction and DC machines. The primary characteristics of these machines are established for steady state behavior as well as for variable speed scenarios. I

  10. Chaotic Boltzmann machines.

    Science.gov (United States)

    Suzuki, Hideyuki; Imura, Jun-ichi; Horio, Yoshihiko; Aihara, Kazuyuki

    2013-01-01

    The chaotic Boltzmann machine proposed in this paper is a chaotic pseudo-billiard system that works as a Boltzmann machine. Chaotic Boltzmann machines are shown numerically to have computing abilities comparable to conventional (stochastic) Boltzmann machines. Since no randomness is required, efficient hardware implementation is expected. Moreover, the ferromagnetic phase transition of the Ising model is shown to be characterised by the largest Lyapunov exponent of the proposed system. In general, a method to relate probabilistic models to nonlinear dynamics by derandomising Gibbs sampling is presented.

  11. Tribology in machine design

    CERN Document Server

    Stolarski, Tadeusz

    1999-01-01

    ""Tribology in Machine Design is strongly recommended for machine designers, and engineers and scientists interested in tribology. It should be in the engineering library of companies producing mechanical equipment.""Applied Mechanics ReviewTribology in Machine Design explains the role of tribology in the design of machine elements. It shows how algorithms developed from the basic principles of tribology can be used in a range of practical applications within mechanical devices and systems.The computer offers today's designer the possibility of greater stringen

  12. Debugging the virtual machine

    Energy Technology Data Exchange (ETDEWEB)

    Miller, P.; Pizzi, R.

    1994-09-02

    A computer program is really nothing more than a virtual machine built to perform a task. The program`s source code expresses abstract constructs using low level language features. When a virtual machine breaks, it can be very difficult to debug because typical debuggers provide only low level machine implementation in formation to the software engineer. We believe that the debugging task can be simplified by introducing aspects of the abstract design into the source code. We introduce OODIE, an object-oriented language extension that allows programmers to specify a virtual debugging environment which includes the design and abstract data types of the virtual machine.

  13. Machine learning with R

    CERN Document Server

    Lantz, Brett

    2013-01-01

    Written as a tutorial to explore and understand the power of R for machine learning. This practical guide that covers all of the need to know topics in a very systematic way. For each machine learning approach, each step in the process is detailed, from preparing the data for analysis to evaluating the results. These steps will build the knowledge you need to apply them to your own data science tasks.Intended for those who want to learn how to use R's machine learning capabilities and gain insight from your data. Perhaps you already know a bit about machine learning, but have never used R; or

  14. Induction machine handbook

    CERN Document Server

    Boldea, Ion

    2002-01-01

    Often called the workhorse of industry, the advent of power electronics and advances in digital control are transforming the induction motor into the racehorse of industrial motion control. Now, the classic texts on induction machines are nearly three decades old, while more recent books on electric motors lack the necessary depth and detail on induction machines.The Induction Machine Handbook fills industry's long-standing need for a comprehensive treatise embracing the many intricate facets of induction machine analysis and design. Moving gradually from simple to complex and from standard to

  15. Design and Simulation of Hydraulic System of Press Machine%压力机液压系统的设计与仿真

    Institute of Scientific and Technical Information of China (English)

    宋晓美; 韩亮

    2014-01-01

    For the problems of the vibration and noise common to hydraulic system of press,the hydraulic and control system applied in the actual production is designed.The principle of the hydraulic system is analyzed and the hydraulic circuit and electric control circuit of the system is simulated by FluidSIM software.%针对压力机液压系统常见的振动及噪声问题,设计了应用于生产实际的压力机液压及控制系统,分析了液压系统原理,并利用FluidSIM软件对该系统的液压回路及电气控制回路进行仿真。

  16. Modelling of the dynamic behaviour of hard-to-machine alloys

    OpenAIRE

    Bäker M.; Shrot A.; Leemet T.; Hokka M.; Kuokkala V.-T.

    2012-01-01

    Machining of titanium alloys and nickel based superalloys can be difficult due to their excellent mechanical properties combining high strength, ductility, and excellent overall high temperature performance. Machining of these alloys can, however, be improved by simulating the processes and by optimizing the machining parameters. The simulations, however, need accurate material models that predict the material behaviour in the range of strains and strain rates that occur in the machining proc...

  17. "In Loco Parentis" Revisited?

    Science.gov (United States)

    Murphree, Carolyn T.

    1986-01-01

    Suggests that many students are not aware of proper etiquette and proposes that business communication instructors offer a short bibliography and a few tips that can help students acquire more polish. (DF)

  18. Design and Modeling of a 3 DOF Machine

    OpenAIRE

    Marjan Sikandar

    2014-01-01

    This paper proposes an IT solution to implement a 3DOF machine by using several design patterns. A Degree of Freedom machine is a motion platform synchronized with the simulation game visually displayed. Through this research we have tried to find an optimal way to implement such a robotic machine that is supposed to be used in different virtual prototypes by industrialists. Since the development cost of an actual product often, is too high to test the initial design, many industrialists now-...

  19. On the Optimal Selection of Electrical Machines Fans

    Directory of Open Access Journals (Sweden)

    Mădălin Costin

    2014-09-01

    Full Text Available In this paper an analytic relationship for electrical machine fan design has been developed. In the particularly case of salient poles synchronous machine (with salient poles – for electromagnetic field excitation or surface mounded permanent magnet, this approach allowed to express the fan power as a function of machine middle axe air gap. This analytic foundation developed may leads to different optimization criteria as specific active materials or costs. Numerical simulations confirm our approach.

  20. Electric vehicle machines and drives design, analysis and application

    CERN Document Server

    Chau, K

    2015-01-01

    A timely comprehensive reference consolidates the research and development of electric vehicle machines and drives for electric and hybrid propulsions • Focuses on electric vehicle machines and drives • Covers the major technologies in the area including fundamental concepts and applications • Emphasis the design criteria, performance analyses and application examples or potentials of various motor drives and machine systems • Accompanying website includes the simulation models and outcomes as supplementary material

  1. Virtual machine vs Real Machine: Security Systems

    Directory of Open Access Journals (Sweden)

    Dr. C. Suresh Gnana Das

    2009-08-01

    Full Text Available This paper argues that the operating system and applications currently running on a real machine should relocate into a virtual machine. This structure enables services to be added below the operating system and to do so without trusting or modifying the operating system or applications. To demonstrate the usefulness of this structure, we describe three services that take advantage of it: secure logging, intrusion prevention and detection, and environment migration. In particular, we can provide services below the guest operating system without trusting or modifying it. We believe providing services at this layer are especially useful for enhancing security and mobility. This position paper describes the general benefits and challenges that arise from running most applications in a virtual machine, and then describes some example services and alternative ways to provide those services.

  2. Research on the Technology of Planarization for LOCOS Process%应用于LOCOS隔离工艺的平坦化技术研究

    Institute of Scientific and Technical Information of China (English)

    高渊; 刘英坤; 邓建国; 梁东升; 董军平

    2012-01-01

    The mechanism of LOCOS process was introduced, and the technology of etch-back for LOCOS was researched. Smooth surface was obtained by adjusting the gas flow rate. The flow rate of CHF3 was 50 mL/min, and the flow rate of O2 was 2 mL/min. The CMP technology for LOCOS process was studied. Polishing rate and precision were controlled by optimizing the parameters of pressure, rotation and slurry, etc. The coherence of planarization is improved and good surface state is attained under the condition that the pressure is 1 psi, the rotation is 25 r/min, and the slurry is 120 mL/min. Compared with the etch-back, the effect of CMP is better. The CMP technology is applied for the production.%介绍了LOCOS隔离技术的原理,研究了应用于LOCOS工艺的反刻平坦化技术,通过调整刻蚀中反应气体流量等工艺参数,在CHF3流量50 mL/min、O2流量2 mL/min条件下,获得了较好的平坦化表面.研究了应用于LOCOS工艺的CMP平坦化技术,通过调整CMP压力、转速、流量等工艺参数,控制了抛光速率和精度,提高平坦化的均匀性,在工艺条件为压力1 psi(1 psi=6.89×103 Pa),转速25 r/min,流量120 mL/min时,获得了良好的平坦化形貌.通过实验对比发现,CMP平坦化效果优于反刻平坦化,适合于实际生产应用.

  3. Dynamic compression of water to 700 GPa: single- and double shock experiments on Sandia's Z machine, first principles simulations, and structure of water planets

    Science.gov (United States)

    Mattsson, Thomas R.

    2011-11-01

    Significant progress has over the last few years been made in high energy density physics (HEDP) by executing high-precision multi-Mbar experiments and performing first-principles simulations for elements ranging from carbon [1] to xenon [2]. The properties of water under HEDP conditions are of particular importance in planetary science due to the existence of ice-giants like Neptune and Uranus. Modeling the two planets, as well as water-rich exoplanets, requires knowing the equation of state (EOS), the pressure as a function of density and temperature, of water with high accuracy. Although extensive density functional theory (DFT) simulations have been performed for water under planetary conditions [3] experimental validation has been lacking. Accessing thermodynamic states along planetary isentropes in dynamic compression experiments is challenging because the principal Hugoniot follows a significantly different path in the phase diagram. In this talk, we present experimental data for dynamic compression of water up to 700 GPa, including in a regime of the phase-diagram intersected by the Neptune isentrope and water-rich models for the exoplanet GJ436b. The data was obtained on the Z-accelerator at Sandia National Laboratories by performing magnetically accelerated flyer plate impact experiments measuring both the shock and re-shock in the sample. The high accuracy makes it possible for the data to be used for detailed model validation: the results validate first principles based thermodynamics as a reliable foundation for planetary modeling and confirm the fine effect of including nuclear quantum effects on the shock pressure. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000. [4pt] [1] M.D. Knudson, D.H. Dolan, and M.P. Desjarlais, SCIENCE

  4. Vane Pump Casing Machining of Dumpling Machine Based on CAD/CAM

    Science.gov (United States)

    Huang, Yusen; Li, Shilong; Li, Chengcheng; Yang, Zhen

    Automatic dumpling forming machine is also called dumpling machine, which makes dumplings through mechanical motions. This paper adopts the stuffing delivery mechanism featuring the improved and specially-designed vane pump casing, which can contribute to the formation of dumplings. Its 3D modeling in Pro/E software, machining process planning, milling path optimization, simulation based on UG and compiling post program were introduced and verified. The results indicated that adoption of CAD/CAM offers firms the potential to pursue new innovative strategies.

  5. Outcomes of loco-regional therapy for down-staging of hepatocellular carcinoma prior to liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Xian-Jie Shi; Xin Jin; Mao-Qiang Wang; Li-Xin Wei; Hui-Yi Ye; Yu-Rong Liang; Ying Luo; Jia-Hong Dong

    2011-01-01

    BACKGROUND: The  number  of  loco-regional  therapies (LRTs)  for  hepatocellular  carcinoma  (HCC)  has  increased dramatically  during  the  past  decade.  Many  patients  with HCC  who  were  beyond  the  Milan  criteria  were  allowed to  receive  a  liver  transplantation  (LT)  once  the  HCC  was successfully  down-staged.  This  retrospective  study  aimed to analyze the outcomes of LRTs prior to LT in patients with HCC beyond the Milan criteria. METHODS: We analyzed 56 patients treated from June 2006 to  March  2010:  22  met  the  Milan  criteria  (T1+T2,  39.3%), 16 had T3 tumors (28.6%), and 11 had T4a tumors (19.6%), while  7  were  suspected  of  tumor  vascular  invasion  (T4b, 12.5%). All patients underwent preoperative LRTs, including transcatheter  arterial  chemoembolization,  radiofrequency ablation,  percutaneous  ethanol  injection,  liver  resection, and/or  microwave  coagulation  therapy.  The  number  of  the patients  who  were  successfully  down-staged  before  LT,  the types  of  LRTs  used  before  LT,  and  their  outcomes  after  LT were recorded. RESULTS: Eleven  patients  had  necrotic  tumors  (pT0,  19.6%); 6 had pT1 tumors (10.7%), 22 had pT2 tumors (39.3%), 6 had pT3 tumors (10.7%), 5 had pT4a tumors (8.9%), and 6 had pT4b tumors  (10.7%).  The  histopathologic  tumors  of  39  patients (69.6%)  were  down-staged  and  met  the  established  Milan criteria  (pT0-2).  Imaging-proven  under-staging  was  present in  5  HCC  patients  (8.9%)  who  had  tumors  involving  the

  6. Investigation of the Machining Stability of a Milling Machine with Hybrid Guideway Systems

    Directory of Open Access Journals (Sweden)

    Jui-Pin Hung

    2016-03-01

    Full Text Available This study was aimed to investigate the machining stability of a horizontal milling machine with hybrid guideway systems by finite element method. To this purpose, we first created finite element model of the milling machine with the introduction of the contact stiffness defined at the sliding and rolling interfaces, respectively. Also, the motorized built-in spindle model was created and implemented in the whole machine model. Results of finite element simulations reveal that linear guides with different preloads greatly affect the dynamic responses and machining stability of the horizontal milling machine. The critical cutting depth predicted at the vibration mode associated with the machine tool structure is about 10 mm and 25 mm in the X and Y direction, respectively, while the cutting depth predicted at the vibration mode associated with the spindle structure is about 6.0 mm. Also, the machining stability can be increased when the preload of linear roller guides of the feeding mechanism is changed from lower to higher amount.

  7. Research of the Processing Simulation Environment with Mitsubishi Gantry Machine Tools (MVR33-39DX) based on VERICUT%基于VERICUT的三菱龙门机床(MVR33-39DX)加工仿真环境研究

    Institute of Scientific and Technical Information of China (English)

    王泰吉; 李世涛; 宋福田; 徐鹏

    2016-01-01

    在应用VERICUT软件构建虚拟环境仿真数控程序时,有时会遇到机床厂商为了机床的一些特殊功能而设定的一些特殊指令,这些指令通常需要在VERICUT软件中单独做出定义.介绍了MVR33-39DX数控龙门铣床中一些特殊指令在VERICUT软件中的配置方式.%When building a virtual CNC machine simulation environment in VERICUT ,sometimes some machines have a few special commands for special features .These commands need to be configured in the VERICUT control system .De-scribe how to define special commands in the VERICUT control system for the MVR33-39DX CNC milling machine .

  8. Creating unorganised machines from memristors

    Science.gov (United States)

    Howard, Gerard; Bull, Larry; Costello, Ben De Lacy; Adamatzky, Andrew

    2012-09-01

    There is growing interest in memristive devices following their recent nanoscale fabrication. This paper describes initial consideration of the implementation of artificial intelligence within predominantly memristive hardware. In particular, versions of Alan Turing's discrete dynamical network formalism — the unorganised machine — are used as the knowledge representation scheme and a population-based search technique is used to design appropriate networks. Issues including memristor count and global network synchrony are compared for two memristive logic implementations (NAND and IMP) on a well-known simulated robotics benchmark task. It is shown that IMP networks are harder to design than NAND, but are simpler to implement and require fewer processor cycles.

  9. Stirling machine operating experience

    Energy Technology Data Exchange (ETDEWEB)

    Ross, B. [Stirling Technology Co., Richland, WA (United States); Dudenhoefer, J.E. [Lewis Research Center, Cleveland, OH (United States)

    1994-09-01

    Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that stirling machines are capable of reliable and lengthy operating lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and are not expected to operate for lengthy periods of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered. The record in this paper is not complete, due to the reluctance of some organizations to release operational data and because several organizations were not contacted. The authors intend to repeat this assessment in three years, hoping for even greater participation.

  10. Perpetual Motion Machine

    Directory of Open Access Journals (Sweden)

    D. Tsaousis

    2008-01-01

    Full Text Available Ever since the first century A.D. there have been relative descriptions of known devices as well as manufactures for the creation of perpetual motion machines. Although physics has led, with two thermodynamic laws, to the opinion that a perpetual motion machine is impossible to be manufactured, inventors of every age and educational level appear to claim that they have invented something «entirely new» or they have improved somebody else’s invention, which «will function henceforth perpetually»! However the fact of the failure in manufacturing a perpetual motion machine till now, it does not mean that countless historical elements for these fictional machines become indifferent. The discussion on every version of a perpetual motion machine on the one hand gives the chance to comprehend the inventor’s of each period level of knowledge and his way of thinking, and on the other hand, to locate the points where this «perpetual motion machine» clashes with the laws of nature and that’s why it is impossible to have been manufactured or have functioned. The presentation of a new «perpetual motion machine» has excited our interest to locate its weak points. According to the designer of it the machine functions with the work produced by the buoyant force

  11. Machine Intelligence and Explication

    NARCIS (Netherlands)

    Wieringa, Roelf J.

    1987-01-01

    This report is an MA ("doctoraal") thesis submitted to the department of philosophy, university of Amsterdam. It attempts to answer the question whether machines can think by conceptual analysis. Ideally. a conceptual analysis should give plausible explications of the concepts of "machine" and "inte

  12. Microsoft Azure machine learning

    CERN Document Server

    Mund, Sumit

    2015-01-01

    The book is intended for those who want to learn how to use Azure Machine Learning. Perhaps you already know a bit about Machine Learning, but have never used ML Studio in Azure; or perhaps you are an absolute newbie. In either case, this book will get you up-and-running quickly.

  13. Machine Intelligence and Explication

    NARCIS (Netherlands)

    Wieringa, Roel

    1987-01-01

    This report is an MA ("doctoraal") thesis submitted to the department of philosophy, university of Amsterdam. It attempts to answer the question whether machines can think by conceptual analysis. Ideally. a conceptual analysis should give plausible explications of the concepts of "machine" and "inte

  14. Coordinate measuring machines

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This document is used in connection with three exercises of 2 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercises concern three aspects of coordinate measuring: 1) Measuring and verification of tolerances on coordinate measuring machines, 2) Traceability...

  15. Simple Machine Junk Cars

    Science.gov (United States)

    Herald, Christine

    2010-01-01

    During the month of May, the author's eighth-grade physical science students study the six simple machines through hands-on activities, reading assignments, videos, and notes. At the end of the month, they can easily identify the six types of simple machine: inclined plane, wheel and axle, pulley, screw, wedge, and lever. To conclude this unit,…

  16. Human Machine Learning Symbiosis

    Science.gov (United States)

    Walsh, Kenneth R.; Hoque, Md Tamjidul; Williams, Kim H.

    2017-01-01

    Human Machine Learning Symbiosis is a cooperative system where both the human learner and the machine learner learn from each other to create an effective and efficient learning environment adapted to the needs of the human learner. Such a system can be used in online learning modules so that the modules adapt to each learner's learning state both…

  17. Machine learning with R

    CERN Document Server

    Lantz, Brett

    2015-01-01

    Perhaps you already know a bit about machine learning but have never used R, or perhaps you know a little R but are new to machine learning. In either case, this book will get you up and running quickly. It would be helpful to have a bit of familiarity with basic programming concepts, but no prior experience is required.

  18. Machine Learning Comparison between WorldView-2 and QuickBird-2-Simulated Imagery Regarding Object-Based Urban Land Cover Classification

    Directory of Open Access Journals (Sweden)

    Tessio Novack

    2011-10-01

    Full Text Available The objective of this study is to compare WorldView-2 (WV-2 and QuickBird-2-simulated (QB-2 imagery regarding their potential for object-based urban land cover classification. Optimal segmentation parameters were automatically found for each data set and the obtained results were quantitatively compared and discussed. Four different feature selection algorithms were used in order to verify to which data set the most relevant object-based features belong to. Object-based classifications were performed with four different supervised algorithms applied to each data set and the obtained accuracies and model performances indexes were compared. Segmentation experiments carried out involving bands exclusively available in the WV-2 sensor generated segments slightly more similar to our reference segments (only about 0.23 discrepancy. Fifty seven percent of the different selected features and 53% of all the 80 selections refer to features that can only be calculated with the additional bands of the WV-2 sensor. On the other hand, 57% of the most relevant features and 63% of the second most relevant features can also be calculated considering only the QB-2 bands. In 10 out of 16 classifications, higher Kappa values were achieved when features related to the additional bands of the WV-2 sensor were also considered. In most cases, classifications carried out with the 8-band-related features generated less complex and more efficient models than those generated only with QB-2 band-related features. Our results lead to the conclusion that spectrally similar classes like ceramic tile roofs and bare soil, as well as asphalt and dark asbestos roofs can be better distinguished when the additional bands of the WV-2 sensor are used throughout the object-based classification process.

  19. Modeling and simulation analysis of a disk brushless doubly-fed machine%盘式无刷双馈电机的建模与仿真分析

    Institute of Scientific and Technical Information of China (English)

    张凤阁; 孟祥权; 李毅

    2011-01-01

    For the problems that the stator and rotor of conventional BDFM have different pole number and the coupling capability is worse,which will affect the efficiency,output torque and power density of the BDFM,a novel brushless doubly-fed machine with disk structure was presented,and the mathematical model of the DBDFM was derived.The general simulation program for the DBDFM was compiled with Matlab language,and the operating characteristics of the motor in different motion states were obtained.The experimental validation was performed to provide the theoretical reference for the research of this motor.The analysis of simulation results shows that the DBDFM is suitable for the timing of windmill or water pump and has wide application prospect.%由于传统无刷双馈电机定、转子具有不同的极对数,其耦合能力差,进而影响电机的效率、输出转矩和功率密度等,提出了一种具有盘式结构的新型无刷双馈电机,并在此基础上推导出盘式无刷双馈电机的数学模型.运用Matlab语言编制了盘式无刷双馈电机的通用仿真程序,得到电机在不同运动状态下的运行特性,并对其进行实验验证,为研究该种电机提供了理论参考.通过仿真结果分析表明,这种新型电机非常适用于风机泵类负载的调速,具有较广的应用前景.

  20. 15 CFR 700.31 - Metalworking machines.

    Science.gov (United States)

    2010-01-01

    ... Drilling and tapping machines Electrical discharge, ultrasonic and chemical erosion machines Forging..., power driven Machining centers and way-type machines Manual presses Mechanical presses, power...

  1. LHC Report: machine development

    CERN Multimedia

    Rogelio Tomás García for the LHC team

    2015-01-01

    Machine development weeks are carefully planned in the LHC operation schedule to optimise and further study the performance of the machine. The first machine development session of Run 2 ended on Saturday, 25 July. Despite various hiccoughs, it allowed the operators to make great strides towards improving the long-term performance of the LHC.   The main goals of this first machine development (MD) week were to determine the minimum beam-spot size at the interaction points given existing optics and collimation constraints; to test new beam instrumentation; to evaluate the effectiveness of performing part of the beam-squeezing process during the energy ramp; and to explore the limits on the number of protons per bunch arising from the electromagnetic interactions with the accelerator environment and the other beam. Unfortunately, a series of events reduced the machine availability for studies to about 50%. The most critical issue was the recurrent trip of a sextupolar corrector circuit –...

  2. Micro-machining.

    Science.gov (United States)

    Brinksmeier, Ekkard; Preuss, Werner

    2012-08-28

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

  3. Introduction to machine learning.

    Science.gov (United States)

    Baştanlar, Yalin; Ozuysal, Mustafa

    2014-01-01

    The machine learning field, which can be briefly defined as enabling computers make successful predictions using past experiences, has exhibited an impressive development recently with the help of the rapid increase in the storage capacity and processing power of computers. Together with many other disciplines, machine learning methods have been widely employed in bioinformatics. The difficulties and cost of biological analyses have led to the development of sophisticated machine learning approaches for this application area. In this chapter, we first review the fundamental concepts of machine learning such as feature assessment, unsupervised versus supervised learning and types of classification. Then, we point out the main issues of designing machine learning experiments and their performance evaluation. Finally, we introduce some supervised learning methods.

  4. 局部复发性鼻咽癌的临床病理学特征%Pathological characteristics of loco-regional recurrent nasopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    雍娟娟; 吴秋良; 宗永生; 侯景辉; 梁建中; 匡亚玲; 奚少彦; 卢佳斌

    2014-01-01

    Purpose To investigate the pathological characteristics of loco-regional recurrent nasopharyngeal carcinoma ( rNPC ) . Methods Nasopharyngeal biopsy specimens of 46 rNPCs and 63 primary NPCs were collected. HE staining, immunohistochemistry and EBV small RNAs ( EBERs) in-situ hybridization were performed. Results The over-expression rates of both p63 and CK5/6 in rNPC were significantly higher than those of primary NPCs (P=0. 005, P=0. 026), while no statistical significance of Ki-67 over-ex-pression existed between the two groups ( P=0. 387 ) . More necrotic tissues, inflammatory exudates, giant bizarre carcinoma cells, desmoplastic stroma, giant bizarre tumor cells and higher degree of squamous differentiation were found in rNPCs. The carcinoma cells of 5 rNPCs were negative for both EBERs in-situ hybridization and LMP-1 immunohistochemical staining. Conclusion The loco-re-gional rNPC has two peaks of latency interval:2~5 and 9~11 years. The loco-regional rNPC cells have higher degree of squamous differentiation with higher expression of p63 and CK5/6, as well as more invasive ability. In addition, both EBERs in-situ hybridization and LMP-1 immunostaining are negative in 10. 87% (5/46) of loco-regional rNPC.%目的:探讨局部复发性鼻咽癌的临床病理学特征。方法收集46例局部复发性鼻咽癌和63例原发性鼻咽癌活检组织,行HE染色、免疫组化、EBERs原位杂交检测。结果局部复发性鼻咽癌中p63和CK5/6的强阳性表达率均高于原发性鼻咽癌(P=0.005和P=0.026);Ki-67的强阳性表达率差异无显著性(P=0.387);组织坏死、炎性渗出和间质促纤维增生明显;畸形瘤巨细胞多见,癌细胞鳞状分化程度更高。5例复发性鼻咽癌细胞EBERs原位杂交和LMP-1免疫组化标记均为阴性。结论(1)局部复发性鼻咽癌有2个复发间歇高峰,即2~5年和9~11年。(2)局部复发性鼻咽癌细胞p63和CK5/6强阳性表达率、鳞状分化程度更高

  5. Man-Man-Machine-Machine Etiquette: Towards an Environment to Investigate Behavioral Rules for Dynamic Man-Machine Teams

    Science.gov (United States)

    2010-10-01

    simulation (compound and environment) Sensor Simulation Agents (Guards, decision support, sensor support) Man-Machine Interface Ground Truth ( RPR ) G...10]). It is desired to make this interface based on existing standards. HLA is chosen for the M4E interface. The HLA RPR FOM is a data exchange...Definitions For M4E we have define the following additional classes to the RPR FOM: Table 1: Additional FOM classes. Object Classes Interaction Classes

  6. Haptics-Augmented Simple-Machine Educational Tools.

    Science.gov (United States)

    Williams, Robert L., II; Chen, Meng-Yun; Seaton, Jeffrey M.

    2003-01-01

    Describes a unique project using commercial haptic interfaces to augment the teaching of simple machines in elementary school. Suggests that the use of haptics in virtual simple-machine simulations has the potential for deeper, more engaging learning. (Contains 13 references.) (Author/YDS)

  7. Multi-modality management for loco-regionally advanced laryngeal and hypopharyngeal cancer: balancing the benefit of efficacy and functional preservation.

    Science.gov (United States)

    Qian, Wei; Zhu, Guopei; Wang, Yulong; Wang, Xiaoshen; Ji, Qinghai; Wang, Yu; Dou, Shengjin

    2014-09-01

    The 5-year overall survival (OS) of loco-regionally advanced laryngeal and hypopharyngeal carcinoma (LA-LHC) has declined over the past two decades following the wide application of non-surgical approaches. We aimed to define the new role of open surgery combined with adjuvant chemoradiotherapy in the treatment of LA-LHC for improving survival while maintaining a functional larynx. In the current study, 90 LA-LHC patients treated with open surgery followed by postoperative RT/CRT in our institute from May 2005 to December 2012 were retrospectively analyzed. OS, disease-free survival (DFS), loco-regional failure-free survival (LRFFS) and distant metastasis-free survival (DMFS) were calculated, and prognostic factors were analyzed. Functional larynx preservation results were evaluated according to the head and neck quality of life (QoL) Scale. With a median follow-up period of 37 months, the 3- and 5-year OS, DFS, LRFFS and DMFS were 71.3, 63.7, 85.9, 73.7 and 55.9, 53.0, 81.6, 71.9 %, respectively. Vascular embolism and extracapsular extension (ECE) of the lymph nodes were prognostic factors for poorer OS (p = 0.045 and 0.046, respectively). Vascular embolism was the only prognostic factor for poorer DMFS (p = 0.005). Patients who underwent a conservative partial laryngectomy (CPL) experienced a higher QoL in the domains of speech, swallowing and emotion. Functional larynx preservation was achieved in 36/45 patients (80 %) who received CPL. The results of our study demonstrated that CPL followed by adequate adjuvant therapy could achieve superior oncological results compared with non-surgical approaches in LA-LHC patients while also maintaining satisfactory functional larynx in a majority of patients.

  8. Positive versus negative sentinel nodes in early breast cancer patients: axillary or loco-regional relapse and survival. A study spanning 2000-2012.

    Science.gov (United States)

    García Fernández, A; Chabrera, C; García Font, M; Fraile, M; Lain, J M; Barco, I; González, C; Gónzalez, S; Reñe, A; Veloso, E; Cassadó, J; Pessarrodona, A; Giménez, N

    2013-10-01

    Sentinel Node Biopsy (SNB) is a minimally invasive alternative to elective axillary lymph node dissection (ALND) for nodal staging in early breast cancer. The present study was conducted to evaluate prognostic implications of a negative sentinel node (SN) versus a positive SN (followed by completion ALND) in a closely followed-up sample of early breast cancer patients. We studied 889 consecutive breast cancer patients operated for 908 primaries. Patients received adjuvant therapy with chemotherapy, hormone therapy and eventually trastuzumab. Radiation therapy was based on tangential radiation fields that usually included axillary level I. Median follow-up was 47 months. Axillary recurrence was seen in 1.2% (2/162) of positive SN patients, and 0.8% (5/625) of negative SN patients (p = n.s.). There was an overall 3.2% loco-regional failure rate (29/908). Incidence of distant recurrence was 3.3% (23/693) for negative SN patients, and 4.6% (9/196) for positive SN patients (p = n.s.). Overall mortality rate was 4% (8/198) for positive SN patients, while the corresponding specific mortality rate was 2.5% (5/198). For patients with negative SNs, overall mortality was 4.9% (34/693), and the specific mortality was 1.4% (19/693) (p = n.s.). We did not find significant differences in axillary/loco-regional relapse, distant metastases, disease-free interval or mortality between SN negative and SN positive patients, with a follow-up over 4 years. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Properties of MgO to 1.2 TPa from high-precision experiments on Sandia's Z machine and first-principles simulations using QMC and DFT

    Science.gov (United States)

    Shulenburger, Luke

    2015-11-01

    MgO is a major constituent of Earth's mantle, the rocky cores of gas giants and is a likely component of the interiors of many exoplanets. The high pressure - high temperature behavior of MgO directly affects equation of state models for planetary structure and formation. In this work, we examine MgO under extreme conditions using experimental and theoretical methods to determine the phase diagram and transport properties. Using plate impact experiments on Sandia's Z facility a low entropy solid-solid phase transition from B1 to B2 is clearly determined. The melting transition, on the other hand, is subtle, involving little to no signal in us-up space. Theoretical work utilizing density functional theory (DFT) provides a complementary picture of the phase diagram. The solid-solid phase transition is identified through a series of quasi-harmonic phonon calculations and thermodynamic integration, while the melt boundary is found using phase coexistence calculations. The calculation of reflectivity along the Hugoniot and the influence of the ionic structure on the transport properties requires particular care because of the underestimation of the band gap and attendant overestimation of transport properties due to the use of semi-local density functional theory. We will explore the impact of this theoretical challenge and its potential solutions in this talk. Finally, understanding the behavior of MgO as the pressure releases from the Hugoniot state is a key ingredient to modeling giant impact events. We explore this regime both through additional DFT calculations and by observing the release state of the MgO into lower impedance materials. The integrated use of DFT simulations and high-accuracy shock experiments together provide a comprehensive understanding of MgO under extreme conditions. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the U

  10. ATS-FNN-Based Modeling and Simulation for Compensation Prediction of FWP Machining Deformation%FWP加工变形补偿预测的ATS-FNN建模及仿真

    Institute of Scientific and Technical Information of China (English)

    邓耀华; 刘桂雄

    2012-01-01

    In order to meet the real-time requirements of the prediction model for deformation compensation of flexible workpiece path (FWP) with complex factors, a ATS-FNN (Adaptive TS Fuzzy Neural Network)-based modeling method for the compensation prediction of FWP machining deformation is proposed. In this method, the adaptive fuzzy clustering method is employed to obtain the antecedent fuzzy membership functions and fuzzy rule fitness of TS-FNN from historical machining data, and the steepest descent method is used as the learning algorithm of the consequent network to quickly calculate the parameters of connection weights. Simulated results indicate that, as compared with the standard TS-FNN, the ATS-FNN reduces a modeling time of 52.34% and a mean square error of the predicted compensation respectively by 36.50% or 33.34% in x or y direction.%针对柔性工件轨迹(FWP)加工变形影响因素复杂、对变形补偿预测模型实时性 要求较高的问题,提出了FWP加工变形补偿预测的自适应TS模糊神经网络(ATS-FNN)建模方法.该方法利用自适应模糊聚类方法从历史加工数据中获取T-S型模糊神经网络(TS-FNN)前件网络的模糊隶属度函数、规则适应度;后件神经网络采用最速下降法作为学习算法,以较快地获得网络连接权值参数.仿真表明,文中构建的ATS-FNN比标准TS型模糊神经网络的建模时间减少52.34%,x、y方向补偿预测值的均方误差分别减少了36.50%和33.34%.

  11. Ozone ensemble forecast with machine learning algorithms

    OpenAIRE

    Mallet, Vivien; Stoltz, Gilles; Mauricette, Boris

    2009-01-01

    International audience; We apply machine learning algorithms to perform sequential aggregation of ozone forecasts. The latter rely on a multimodel ensemble built for ozone forecasting with the modeling system Polyphemus. The ensemble simulations are obtained by changes in the physical parameterizations, the numerical schemes, and the input data to the models. The simulations are carried out for summer 2001 over western Europe in order to forecast ozone daily peaks and ozone hourly concentrati...

  12. Tube bending on the roll machine

    Science.gov (United States)

    Nepershin, Rostislav I.

    2013-10-01

    Computer simulation of the elastic-plastic tube bending by pushing on three-roll machine with work hardening effect consideration is presented. Non-steady tube bending process for specified curvature is simulated with axis of bending roll displacement, followed by transfer to the steady-state bending process. Estimation of curvature, constrained by tube section elliptical distortion modeled by plastic hinge mechanism is given. Elastic-plastic bending moment versus curvature and critical curvature estimation reasonably correlated with experiments.

  13. Finite Element Method in Machining Processes

    CERN Document Server

    Markopoulos, Angelos P

    2013-01-01

    Finite Element Method in Machining Processes provides a concise study on the way the Finite Element Method (FEM) is used in the case of manufacturing processes, primarily in machining. The basics of this kind of modeling are detailed to create a reference that will provide guidelines for those who start to study this method now, but also for scientists already involved in FEM and want to expand their research. A discussion on FEM, formulations and techniques currently in use is followed up by machining case studies. Orthogonal cutting, oblique cutting, 3D simulations for turning and milling, grinding, and state-of-the-art topics such as high speed machining and micromachining are explained with relevant examples. This is all supported by a literature review and a reference list for further study. As FEM is a key method for researchers in the manufacturing and especially in the machining sector, Finite Element Method in Machining Processes is a key reference for students studying manufacturing processes but al...

  14. FUZZY NEURAL NETWORK FOR MACHINE PARTS RECOGNITION SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Luo Xiaobin; Yin Guofu; Chen Ke; Hu Xiaobing; Luo Yang

    2003-01-01

    The primary purpose is to develop a robust adaptive machine parts recognition system. A fuzzy neural network classifier is proposed for machine parts classifier. It is an efficient modeling method. Through learning, it can approach a random nonlinear function. A fuzzy neural network classifier is presented based on fuzzy mapping model. It is used for machine parts classification. The experimental system of machine parts classification is introduced. A robust least square back-propagation (RLSBP) training algorithm which combines robust least square (RLS) with back-propagation (BP) algorithm is put forward. Simulation and experimental results show that the learning property of RLSBP is superior to BP.

  15. Machine Learning and Radiology

    Science.gov (United States)

    Wang, Shijun; Summers, Ronald M.

    2012-01-01

    In this paper, we give a short introduction to machine learning and survey its applications in radiology. We focused on six categories of applications in radiology: medical image segmentation, registration, computer aided detection and diagnosis, brain function or activity analysis and neurological disease diagnosis from fMR images, content-based image retrieval systems for CT or MRI images, and text analysis of radiology reports using natural language processing (NLP) and natural language understanding (NLU). This survey shows that machine learning plays a key role in many radiology applications. Machine learning identifies complex patterns automatically and helps radiologists make intelligent decisions on radiology data such as conventional radiographs, CT, MRI, and PET images and radiology reports. In many applications, the performance of machine learning-based automatic detection and diagnosis systems has shown to be comparable to that of a well-trained and experienced radiologist. Technology development in machine learning and radiology will benefit from each other in the long run. Key contributions and common characteristics of machine learning techniques in radiology are discussed. We also discuss the problem of translating machine learning applications to the radiology clinical setting, including advantages and potential barriers. PMID:22465077

  16. The basic anaesthesia machine.

    Science.gov (United States)

    Gurudatt, Cl

    2013-09-01

    After WTG Morton's first public demonstration in 1846 of use of ether as an anaesthetic agent, for many years anaesthesiologists did not require a machine to deliver anaesthesia to the patients. After the introduction of oxygen and nitrous oxide in the form of compressed gases in cylinders, there was a necessity for mounting these cylinders on a metal frame. This stimulated many people to attempt to construct the anaesthesia machine. HEG Boyle in the year 1917 modified the Gwathmey's machine and this became popular as Boyle anaesthesia machine. Though a lot of changes have been made for the original Boyle machine still the basic structure remains the same. All the subsequent changes which have been brought are mainly to improve the safety of the patients. Knowing the details of the basic machine will make the trainee to understand the additional improvements. It is also important for every practicing anaesthesiologist to have a thorough knowledge of the basic anaesthesia machine for safe conduct of anaesthesia.

  17. The basic anaesthesia machine

    Directory of Open Access Journals (Sweden)

    C L Gurudatt

    2013-01-01

    Full Text Available After WTG Morton′s first public demonstration in 1846 of use of ether as an anaesthetic agent, for many years anaesthesiologists did not require a machine to deliver anaesthesia to the patients. After the introduction of oxygen and nitrous oxide in the form of compressed gases in cylinders, there was a necessity for mounting these cylinders on a metal frame. This stimulated many people to attempt to construct the anaesthesia machine. HEG Boyle in the year 1917 modified the Gwathmey′s machine and this became popular as Boyle anaesthesia machine. Though a lot of changes have been made for the original Boyle machine still the basic structure remains the same. All the subsequent changes which have been brought are mainly to improve the safety of the patients. Knowing the details of the basic machine will make the trainee to understand the additional improvements. It is also important for every practicing anaesthesiologist to have a thorough knowledge of the basic anaesthesia machine for safe conduct of anaesthesia.

  18. Reluctance Machine for a Hollow Cylinder Flywheel

    Directory of Open Access Journals (Sweden)

    Magnus Hedlund

    2017-03-01

    Full Text Available A hollow cylinder flywheel rotor with a novel outer rotor switched reluctance machine (SRM mounted on the interior rim is presented, with measurements, numerical analysis and analytical models. Practical experiences from the construction process are also discussed. The flywheel rotor does not have a shaft and spokes and is predicted to store 181 Wh / kg at ultimate tensile strength (UTS according to simulations. The novel SRM is an axial flux machine, chosen due to its robustness and tolerance for high strain. The computed maximum tip speed of the motor at UTS is 1050 m / s . A small-scale proof-of-concept electric machine prototype has been constructed, and the machine inductance has been estimated from measurements of voltage and current and compared against results from analytical models and finite element analysis (FEA. The prototype measurements were used to simulate operation during maximal speed for a comparison towards other high-speed electric machines, in terms of tip speed and power. The mechanical design of the flywheel was performed with an analytical formulation assuming planar stress in concentric shells of orthotropic (unidirectionally circumferentially wound carbon composites. The analytical approach was verified with 3D FEA in terms of stress and strain.

  19. 基于改进最小二乘支持向量机的电力机车牵引电机建模%Traction Motor Simulation Model of Electric Locomotive Based on Improved Least Squares Support Vector Machine

    Institute of Scientific and Technical Information of China (English)

    李娜; 杨恒; 屈志坚; 杨罡

    2011-01-01

    Considering the nonlinear magnetization characteristics of the traction motor of the electric locomotive, the paper presents the least squares support vector machine (LS-SVM) to acquire the fitting of magnetization curve. In order to shorten the modeling time, the three step search method is used to get the optimized parameters of LS-SVM. Theoretical analysis and simulation results show that the method facilitates optimization of the parameters and shortening of the modeling time of LS-SVM. The traction motor simulation model is built on the basis of the improved LS-SVM. The simulation results show that the proposed traction motor model of the electric locomotive is of high accuracy and is applicable in research of the performance and control strategy of the main circuit of the electric locomotive.%介绍利用最小二乘支持向量机的回归理论对牵引电机磁化曲线进行拟合,从而建立准确的电力机车牵引电机模型的方法.针对最小二乘支持向量机参数选择耗时长的问题,提出一种基于三步搜索技术的参数选择方法.理论分析及仿真结果表明,该方法可优化选择最小二乘支持向量机的参数,并可提高最小二乘支持向量机的建模速度.将该方法用于电力机车牵引电机建模的参数选择,仿真结果表明,该方法建立的电力机车牵引电机模型精确度高,可用于对电力机车主电路性能及控制策略的研究.

  20. 一种模拟实际工作状态的空气弹簧疲劳试验机的设计%Design for Air Spring Fatigue Testing Machine by Simulation of Actual Working Conditions

    Institute of Scientific and Technical Information of China (English)

    毛茜; 何江华; 赵克刚

    2016-01-01

    A fatigue testing machine is designed in this paper,to acquire relatively real longevity of air spring by simulating the working state of real vehicles.The crank radius range under the condition of am-plitude is deduced by the geometric relationship and crank rod mechanism,and the optimal value of crank radius is determined by using the least square method.The maximal force required to drive the beam is ob-tained by the combination of the simulation and experiment.The test result shows a reduction from 36 000 N to less than 9 000 N by choosing to install two symmetrically instead of install one.The ADAMS soft-ware is used to simulate the movement condition of a cantilever and the speed curve of the center of clamp. The input power of the cantilever is calculated at 4.13 kW.Considering the transmission efficiency of the system and the power factor of the motor,the motor power is determined and the motor is selected.%设计了一种可以模拟实车工作状态的疲劳试验机,能较真实地获取空气弹簧使用寿命。由几何关系和曲柄连杆运动原理,推导得到所要求振幅的曲柄半径范围值,由最小二乘法确定最佳的曲柄半径值。采用仿真和试验相结合的方法,得到驱动悬梁所需的可能最大力,结果显示对称安装2个较单个安装最大力从36000 N降至9000 N以下,节能效果显著;用ADAMS软件模拟悬梁的运动状况,获取夹具中心点的运动速度曲线;计算得到悬梁所需的输入功率为4.13 kW,结合系统传动效率和电机功率因数,确定电机功率,完成电机选型。