Sample records for hard drive space

  1. CSI: Hard Drive

    Sturgeon, Julie


    Acting on information from students who reported seeing a classmate looking at inappropriate material on a school computer, school officials used forensics software to plunge the depths of the PC's hard drive, searching for evidence of improper activity. Images were found in a deleted Internet Explorer cache as well as deleted file space.…

  2. 2TB hard disk drive

    This particular object was used up until 2012 in the Data Centre. It slots into one of the Disk Server trays. Hard disks were invented in the 1950s. They started as large disks up to 20 inches in diameter holding just a few megabytes (link is external). They were originally called "fixed disks" or "Winchesters" (a code name used for a popular IBM product). They later became known as "hard disks" to distinguish them from "floppy disks (link is external)." Hard disks have a hard platter that holds the magnetic medium, as opposed to the flexible plastic film found in tapes and floppies.

  3. Visual inspection technology in the hard disc drive industry

    Muneesawang, Paisarn


    A presentation of the use of computer vision systems to control manufacturing processes and product quality in the hard disk drive industry. Visual Inspection Technology in the Hard Disk Drive Industry is an application-oriented book borne out of collaborative research with the world's leading hard disk drive companies. It covers the latest developments and important topics in computer vision technology in hard disk drive manufacturing, as well as offering a glimpse of future technologies.

  4. 77 FR 8284 - Western Digital Technologies, Inc., Hard Drive Development Engineering Group Irvine (Formerly at...


    ... workers of Western Digital Technologies, Inc., Hard Drive Development Engineering Group, Lake Forest... Western Digital Technologies, Inc., Hard Drive Development Engineering Group, Irvine (formerly at Lake... Employment and Training Administration Western Digital Technologies, Inc., Hard Drive Development...

  5. 76 FR 61746 - Western Digital Technologies, Inc.: Hard Drive Development Engineering Group Irvine (Formerly at...


    ... Western Digital Technologies, Inc., Hard Drive Development Engineering Group, Lake Forest, California... workers and former workers of Western Digital Technologies, Inc., Hard Drive Development Engineering Group... Employment and Training Administration Western Digital Technologies, Inc.: Hard Drive Development...

  6. Sensorless optimal sinusoidal brushless direct current for hard disk drives

    Soh, C. S.; Bi, C.


    Initiated by the availability of digital signal processors and emergence of new applications, market demands for permanent magnet synchronous motors have been surging. As its back-emf is sinusoidal, the drive current should also be sinusoidal for reducing the torque ripple. However, in applications like hard disk drives, brushless direct current (BLDC) drive is adopted instead of sinusoidal drive for simplification. The adoption, however, comes at the expense of increased harmonics, losses, torque pulsations, and acoustics. In this paper, we propose a sensorless optimal sinusoidal BLDC drive. First and foremost, the derivation for an optimal sinusoidal drive is presented, and a power angle control scheme is proposed to achieve an optimal sinusoidal BLDC. The scheme maintains linear relationship between the motor speed and drive voltage. In an attempt to execute the sensorless drive, an innovative power angle measurement scheme is devised, which takes advantage of the freewheeling diodes and measures the power angle through the detection of diode voltage drops. The objectives as laid out will be presented and discussed in this paper, supported by derivations, simulations, and experimental results. The proposed scheme is straightforward, brings about the benefits of sensorless sinusoidal drive, negates the need for current sensors by utilizing the freewheeling diodes, and does not incur additional cost.

  7. 76 FR 10403 - Western Digital Technologies, Inc., Coporate Headquaters/Hard Drive Development Division, Lake...


    ... Drive Development Division, Lake Forest, California (Western Digital Technologies). The Department's... former workers of Western Digital Technologies, Inc., Corporate Headquarters/Hard Drive Development... Employment and Training Administration Western Digital Technologies, Inc., Coporate Headquaters/Hard...

  8. Radiation Hardness Assurance for Space Systems

    Poivey, Christian; Day, John H. (Technical Monitor)


    The space radiation environment can lead to extremely harsh operating conditions for on-board electronic box and systems. The characteristics of the radiation environment are highly dependent on the type of mission (date, duration and orbit). Radiation accelerates the aging of the electronic parts and material and can lead to a degradation of electrical performance; it can also create transient phenomena on parts. Such damage at the part level can induce damage or functional failure at electronic box, subsystem, and system levels. A rigorous methodology is needed to ensure that the radiation environment does not compromise the functionality and performance of the electronics during the system life. This methodology is called hardness assurance. It consists of those activities undertaken to ensure that the electronic piece parts placed in the space system perform to their design specifications after exposure to the space environment. It deals with system requirements, environmental definitions, part selection, part testing, shielding and radiation tolerant design. All these elements should play together in order to produce a system tolerant to.the radiation environment. An overview of the different steps of a space system hardness assurance program is given in section 2. In order to define the mission radiation specifications and compare these requirements to radiation test data, a detailed knowledge of the space environment and the corresponding electronic device failure mechanisms is required. The presentation by J. Mazur deals with the Earth space radiation environment as well as the internal environment of a spacecraft. The presentation by J. Schwank deals with ionization effects, and the presentation by T. Weatherford deals with Single particle Event Phenomena (SEP) in semiconductor devices and microcircuits. These three presentations provide more detailed background to complement the sections 3 and 4. Part selection and categorization are discussed in section

  9. Radiation Hardness Assurance (RHA) for Space Systems

    Poivey, Christian; Buchner, Stephen


    This presentation discusses radiation hardness assurance (RHA) for space systems, providing both the programmatic aspects of RHA and the RHA procedure. RHA consists of all activities undertaken to ensure that the electronics and materials of a space system perform to their design specifications after exposure to the space radiation environment. RHA also pertains to environment definition, part selection, part testing, spacecraft layout, radiation tolerant design, and mission/system/subsystems requirements. RHA procedure consists of establishing mission requirements, defining and evaluating the radiation hazard, selecting and categorizing the appropriate parts, and evaluating circuit response to hazard. The RHA approach is based on risk management and is confined only to parts, it includes spacecraft layout, system/subsystem/circuit design, and system requirements and system operations. RHA should be taken into account in the early phases of a program including the proposal and feasibility analysis phases.

  10. Space Drive Physics: Introduction and Next Steps

    Millis, M. G.

    Research toward the visionary goal of propellantless ``space drives'' is introduced, covering key physics issues and a listing of roughly 2-dozen approaches. The targeted advantage of a space drive is to circumvent the propellant constraints of rockets and the maneuvering limits of light sails by using the interactions between the spacecraft and its surrounding space for propulsion. At present, the scientific foundations from which to engineer a space drive have not been discovered and, objectively, might be impossible. Although no propulsion breakthroughs appear imminent, the subject has matured to where the relevant questions have been broached and are beginning to be answered. The critical make-break issues include; conservation of momentum, uncertain sources of reaction mass, and the net-external thrusting requirement. Note: space drives are not necessarily faster- than-light devices. Speed limits are a separate, unanswered issue. Relevant unsolved physics includes; the sources and mechanisms of inertial frames, coupling of gravitation and electromagnetism, and the nature of the quantum vacuum. The propulsion approaches span mostly stages 1 through 3 of the scientific method (defining the problem, collecting data, and articulating hypotheses), while some have matured to stage 4 (testing hypotheses). Nonviable approaches include `stiction drives,' `gyroscopic antigravity,' and `lifters.' No attempt is made to gauge the prospects of the remaining approaches. Instead, a list of next-step research questions is derived from the examination of these goals, unknowns, and concepts.

  11. Low Molecular Weight Z-Tetraol Boundary Lubricant Films in Hard Disk Drives

    R. J. Waltman


    Full Text Available Lower molecular weight Z-Tetraol films exhibit increased mechanical spacing in the slider-disk interface due to a lower z-profile. An increased resistance to lubricant disturbance on the disk surface (e.g., lube moguls with decreasing film thickness is attributed to an increasing contribution from the polar component of the disjoining pressure. Evaporative loss at temperatures typically encountered in a hard-disk drive also increases with decreasing molecular weight but is strongly dependent on the initial bonded fraction.

  12. failure analysis and shock protection of external hard disk drive


    Technology for processing and storage of data in portable external storage hard disks has ... system was used to simulate the impact of stress on the structure of the hard disk before and ... highlighted [1] that mechanical vibration and shock.

  13. Head-Positioning Control Using Virtual Resonant Modes in a Hard Disk Drive

    Atsumi, Takenori

    In conventional control systems in hard disk drives, it is difficult to compensate for disturbances above the primary mechanical resonance. In this paper, a design method that uses a virtual resonant mode in head-positioning systems of hard disk drives was developed. The virtual resonant mode is a digital filter that works like a mechanical resonant mode. Using the proposed method, stable resonant modes in a control system can be designed with a high degree of accuracy to compensate for disturbances whose frequencies are higher than that of the primary mechanical resonance. Application of this method to a hard disk drive showed that it significantly suppresses disturbances beyond the primary mechanical resonance.

  14. Disposal of waste computer hard disk drive: data destruction and resources recycling.

    Yan, Guoqing; Xue, Mianqiang; Xu, Zhenming


    An increasing quantity of discarded computers is accompanied by a sharp increase in the number of hard disk drives to be eliminated. A waste hard disk drive is a special form of waste electrical and electronic equipment because it holds large amounts of information that is closely connected with its user. Therefore, the treatment of waste hard disk drives is an urgent issue in terms of data security, environmental protection and sustainable development. In the present study the degaussing method was adopted to destroy the residual data on the waste hard disk drives and the housing of the disks was used as an example to explore the coating removal process, which is the most important pretreatment for aluminium alloy recycling. The key operation points of the degaussing determined were: (1) keep the platter plate parallel with the magnetic field direction; and (2) the enlargement of magnetic field intensity B and action time t can lead to a significant upgrade in the degaussing effect. The coating removal experiment indicated that heating the waste hard disk drives housing at a temperature of 400 °C for 24 min was the optimum condition. A novel integrated technique for the treatment of waste hard disk drives is proposed herein. This technique offers the possibility of destroying residual data, recycling the recovered resources and disposing of the disks in an environmentally friendly manner.

  15. Multicore Rad Hard Processing in Space Project

    National Aeronautics and Space Administration — Space Micro proposes to research and develop a high performance computing/processing platform for NASA space missions. Leveraging our previous work for both NASA and...

  16. Hard Disk/Solid State Drive Synergy in Support of Data-Intensive Computing

    Liu,Ke [Los Alamos National Laboratory; Jiang, Song [Los Alamos National Laboratory; Davis, Kei [Los Alamos National Laboratory


    Data-intensive applications are becoming increasingly common in high-performance computing. Examples include combustion simulation, human genome analysis, and satellite image processing. Efficient access of data sets is critical to the performance of these applications. Because of the size of the data today's economically feasible approach is to store the data files on an array of hard disks or data servers equipped with hard disks and managed by a parallel file system such as PVFS or Lustre wherein the data is striped over a (large) number of disks for high aggregate I/O throughout. With file striping, a request for a segment of logically contiguous file space is decomposed into multiple sub-requests, each to a different server. While the data unit for this striping is usually reasonably large to benefit disk efficiency, the first and/or last sub-requests can be much smaller than the striping unit if the request does not align with the striping pattern, severely compromising hard disk efficiency and thus application performance. We propose to exploit solid state drives (SSD), whose efficiency is much less sensitive to small random accesses, to enable the alignment of requests to disk with the data striping pattern. In this scheme hard disks mainly serve large, aligned, sequential requests, with SSDs serving small or unaligned requests, thus respecting the relative cost, performance, and durability characteristics of the two media, and thereby achieving synergy in performance/cost. We will describe the design of the proposed scheme, its implementation on CCS-7's Darwin cluster, and performance results.

  17. CD-ROM optics for flying height measurement in hard disk drives

    Tunstall, Glen; Jenkins, David F. L.; Clegg, Warwick W.; Li, Amei; Davey, Paul


    One of the most critical and effective parameters in increasing areal density is the flying height or spacing between the read-write head and the recording disk medium. As the flying height reduces to near contact, the head flies around 5 nm about the disk surface. To date, optical interferometry has been the major means for the characterization of this parameter. However, it is difficult to use it directly to measure the flying height on a sealed drive. To circumvent this limitation, a system based upon CD-ROM optics has been designed. The results from the system are correlated to measurements of suspension arm movement and disk flutter using poly-vinylidine-flouride (PVdF) strain sensors. A CD-ROM drive utilizes a laser with photodiodes to read data from the disk. The photo detector output responds linearly to changes in the lens-disk separation. In our system two CD-ROM heads are located within a rig that allows independent positioning in all three planes. The optics are configured to reflect off of a typical hard disk drive disk and the slider. To validate its performance a thin (110 micron) sheet of poly vinylidine flouride (PVdF) piezoelectric material is bonded to the suspension arm to measure the average induced strain. A further PVdF sensor was used to measure the edge displacement of the disk due to disk bending. The sensor used was in a cantilever configuration, with one end rigidly bonded to the drive chassis in a manner that pre-tensions the cantilever against the disk. Any movement of the disk would change the strain induced in the cantilever.

  18. Enthalpy versus entropy: What drives hard-particle ordering in condensed phases?

    Anthamatten, Mitchell; Ou, Jane J.; Weinfeld, Jeffrey A.; Chen, Shaw H.


    In support of mesoscopic-scale materials processing, spontaneous hard-particle ordering has been actively pursued for over a half-century. The generally accepted view that entropy alone can drive hard particle ordering is evaluated. A thermodynamic analysis of hard particle ordering was conducted and shown to agree with existing computations and experiments. Conclusions are that (i) hard particle ordering transitions between states in equilibrium are forbidden at constant volume but are allowed at constant pressure; (ii) spontaneous ordering transitions at constant pressure are driven by enthalpy, and (iii) ordering under constant volume necessarily involves a non-equilibrium initial state which has yet to be rigorously defined.

  19. Dynamic characterisation of the head media interface in hard disk drives using novel sensor systems

    Tunstall, G A


    Hard disk drives function perfectly satisfactorily when used in a stable environment, but in certain applications they are subjected to shock and vibration. During the work reported in this thesis it has been found that when typical hard disk drives are subjected to vibration, data transfer failure is found to be significant at frequencies between 440Hz and 700Hz, at an extreme, failing at only 1g of sinusoidal vibration. These failures can largely be attributed to two key components: the suspension arm and the hard disk. At non-critical frequencies of vibration the typical hard disk drive can reliably transfer data whilst subjected to as much as 45g. When transferring data to the drive controller, the drive's operations are controlled and monitored using BIOS commands. Examining the embedded error signals proved that the drive predominantly failed due to tracking errors. Novel piezo-electric sensors have been developed to measure unobtrusively suspension arm and disk motion, the results from which show the d...

  20. Study of facing target sputtered diamond-like carbon overcoats for hard disk drive media

    Seet, H.L., E-mail: [Data Storage Institute, A*STAR Agency for Science, Technology and Research, 5 Engineering Drive 1, 117608 (Singapore); Ng, K.K.; Chen, X.Y. [Data Storage Institute, A*STAR Agency for Science, Technology and Research, 5 Engineering Drive 1, 117608 (Singapore); Yang, P. [Singapore Synchrotron Light Source (SSLS), National University of Singapore, 5 Research Link, 117603 (Singapore); Shen, L. [Institute of Materials Research and Engineering, A*STAR Agency for Science, Technology and Research, 3 Research Link, 117602 (Singapore); Ji, R.; Ng, H.X.; Lim, C.B. [Data Storage Institute, A*STAR Agency for Science, Technology and Research, 5 Engineering Drive 1, 117608 (Singapore)


    The demand for higher areal density in the hard disk drive industry has fuelled extensive research efforts and focuses on magnetic spacing reduction. In the head–disk interface arena, one of the key focuses is to reduce the carbon overcoat thickness without compromising the overcoat protection performance. Thus, in the search for alternative methods to reduce the carbon overcoat thickness, the facing target sputtering (FTS) process for diamond-like carbon deposition has been investigated. The resulting properties have been presented in this paper, with comparison to conventional diamond-like carbon (DLC) layers by other processes such as chemical vapor deposition and reactive sputtering with nitrogen. X-ray reflectometry results showed that facing target sputtered DLC samples displayed significantly higher density, at 2.87 g/cm{sup 3}, as compared to hydrogenated and nitrogenated DLC samples. This was attributed to the higher sp{sup 3} content, as obtained by X-ray photoelectron spectroscopy measurements. As a result of the high sp{sup 3} content, hardness of the FTS deposited samples was higher than that of the hydrogenated and nitrogenated DLC samples. In addition, the surface energy of FTS samples was observed to be comparable, but lower, than that of nitrogenated DLC samples through contact angle measurements. Clearances comparable to that of conventional DLC samples were achieved and the sample disks were flyable. Wear performance tests also revealed more wear resistance for the FTS deposited DLC samples, but also higher head wear. - Highlights: • Facing target sputtered (FTS) diamond-like carbon (DLC) samples were studied. • FTS DLC samples possess higher density and hardness. • Surface conditions and flyability performances for FTS DLC samples were comparable. • Wear tests on FTS DLC samples showed lower media wear, but higher head wear.

  1. Design and Implementation of a Hall Effect Sensor Array Applied to Recycling Hard Drive Magnets

    Kisner, Roger [ORNL; Lenarduzzi, Roberto [ORNL; Killough, Stephen M [ORNL; McIntyre, Timothy J [ORNL


    Rare earths are an important resource for many electronic components and technologies. Examples abound including Neodymium magnets used in mobile devices and computer hard drives (HDDs), and a variety of renewable energy technologies (e.g., wind turbines). Approximately 21,000 metric tons of Neodymium is processed annually with less than 1% being recycled. An economic system to assist in the recycling of magnet material from post-consumer goods, such as Neodymium Iron Boron magnets commonly found in hard drives is presented. A central component of this recycling measurement system uses an array of 128 Hall Effect sensors arranged in two columns to detect the magnetic flux lines orthogonal to the HDD. Results of using the system to scan planar shaped objects such as hard drives to identify and spatially locate rare-earth magnets for removal and recycling from HDDs are presented. Applications of the sensor array in other identification and localization of magnetic components and assemblies will be presented.

  2. Robust H∞ stabilization of a hard disk drive system with a single-stage actuator

    Harno, Hendra G.; Kiin Woon, Raymond Song


    This paper considers a robust H∞ control problem for a hard disk drive system with a single stage actuator. The hard disk drive system is modeled as a linear time-invariant uncertain system where its uncertain parameters and high-order dynamics are considered as uncertainties satisfying integral quadratic constraints. The robust H∞ control problem is transformed into a nonlinear optimization problem with a pair of parameterized algebraic Riccati equations as nonconvex constraints. The nonlinear optimization problem is then solved using a differential evolution algorithm to find stabilizing solutions to the Riccati equations. These solutions are used for synthesizing an output feedback robust H∞ controller to stabilize the hard disk drive system with a specified disturbance attenuation level.

  3. Microorganisms and biomolecules in space hard environment

    Horneck, G.


    Microorganisms and biomolecules exposed to space vacuum and to different intensities of selected wavelengths of solar ultraviolet radiation is studied. The influence of these factors, applied singly or simultaneously, on the integrity of microbial systems and biomolecules is measured. Specifically, this experiment will study in Bacillus subtilis spores (1) disturbances in subsequent germination, outgrowth, and colony formation; (2) photochemical reactions of the DNA and protein in vivo and in vitro and their role in biological injury; and (3) the efficiency of repair processes in these events.

  4. 75 FR 65517 - Western Digital Technologies, Inc., Corporate Headquarters/Hard Drive Development Division, Lake...


    ... Employment and Training Administration Western Digital Technologies, Inc., Corporate Headquarters/Hard Drive Development Division, Lake Forest, CA; Notice of Affirmative Determination Regarding Application for... determination was issued on August 5, 2010 and published in the Federal Register on August 23, 2010 (75 FR...

  5. Model of Head-Positioning Error Due to Rotational Vibration of Hard Disk Drives

    Matsuda, Yasuhiro; Yamaguchi, Takashi; Saegusa, Shozo; Shimizu, Toshihiko; Hamaguchi, Tetsuya

    An analytical model of head-positioning error due to rotational vibration of a hard disk drive is proposed. The model takes into account the rotational vibration of the base plate caused by the reaction force of the head-positioning actuator, the relationship between the rotational vibration and head-track offset, and the sensitivity function of track-following feedback control. Error calculated by the model agrees well with measured error. It is thus concluded that this model can predict the data transfer performance of a disk drive in read mode.

  6. A production throughput forecasting system in an automated hard disk drive test operation using GRNN

    Nara Samattapapong


    Originality/value: The production throughput volume is a key performance index of hard disk drive manufacturing systems that need to be forecast. Because of the production throughput forecasting result is useful information for management team to respond to any changing in production processes and resources allocation. However, a practically forecasting system for production throughput has not been described in detail yet. The experiments were conducted on a real data set from the final testing operation of hard disk drive manufacturing factory by using Visual Basics Application on Microsoft Excel© to develop preliminary forecasting system on testing and verification process. The experimental result shows that the proposed model is superior to the performance of the current forecasting system.

  7. Active Vibration Control of a Microactuator for the Hard Disk Drive Using Self-Sensing Actuation

    Minoru Sasaki; Yoshihiro Inoue; Hiroyuki Yamada


    This paper presents the self-sensing control of a microactuator for hard disk drives. The microactuator uses a PZT actuator pair installed on the suspension assembly. The self-sensing microactuator forms a combined sensing and actuation mechanism. Direct velocity feedback and positive position feedback are used in this paper. Our experimental results show that both strategies are effective in suppressing vibrational modes and successfully demonstrate the feasibility of using a self-sensing ac...

  8. Integration of Piezoelectric Sensing and Control for Nano-Scale Vibration Suppression in Hard Disk Drives

    Felix, Sarah Helen


    This work takes an integrated mechatronic approach to combine a novel sensing scheme with appropriate control methods to improve vibration suppression in hard disk drives (HDDs). Thin-film piezoelectric ZnO strain sensors were integrated into a PZT-actuated HDD suspension by fabricating the sensors directly onto the steel suspension structure that carries the read/write head. This technology allowed for the addition of sensors at arbitrary locations without significantly altering the dynami...

  9. Integration of Piezoelectric Sensing and Control for Nano-Scale Vibration Suppression in Hard Disk Drives

    Felix, Sarah Helen


    This work takes an integrated mechatronic approach to combine a novel sensing scheme with appropriate control methods to improve vibration suppression in hard disk drives (HDDs). Thin-film piezoelectric ZnO strain sensors were integrated into a PZT-actuated HDD suspension by fabricating the sensors directly onto the steel suspension structure that carries the read/write head. This technology allowed for the addition of sensors at arbitrary locations without significantly altering the dynami...

  10. A production throughput forecasting system in an automated hard disk drive test operation using GRNN

    Samattapapong, N.; Afzulpurkar, N.


    The goal of this paper is to develop a pragmatic system of a production throughput forecasting system for an automated test operation in a hard drive manufacturing plant. The accurate forecasting result is necessary for the management team to response to any changes in the production processes and the resources allocations. In this study, we design a production throughput forecasting system in an automated test operation in hard drive manufacturing plant. In the proposed system, consists of three main stages. In the first stage, a mutual information method was adopted for selecting the relevant inputs into the forecasting model. In the second stage, a generalized regression neural network (GRNN) was implemented in the forecasting model development phase. Finally, forecasting accuracy was improved by searching the optimal smoothing parameter which selected from comparisons result among three optimization algorithms: particle swarm optimization (PSO), unrestricted search optimization (USO) and interval halving optimization (IHO). The experimental result shows that (1) the developed production throughput forecasting system using GRNN is able to provide forecasted results close to actual values, and to projected the future trends of production throughput in an automated hard disk drive test operation; (2) An IHO algorithm performed as superiority appropriate optimization method than the other two algorithms. (3) Compared with current forecasting system in manufacturing, the results show that the proposed system’s performance is superior to the current system in prediction accuracy and suitable for real-world application. The production throughput volume is a key performance index of hard disk drive manufacturing systems that need to be forecast. Because of the production throughput forecasting result is useful information for management team to respond to any changing in production processes and resources allocation. However, a practically forecasting system for

  11. Computational topology for configuration spaces of hard disks.

    Carlsson, Gunnar; Gorham, Jackson; Kahle, Matthew; Mason, Jeremy


    We explore the topology of configuration spaces of hard disks experimentally and show that several changes in the topology can already be observed with a small number of particles. The results illustrate a theorem of Baryshnikov, Bubenik, and Kahle that critical points correspond to configurations of disks with balanced mechanical stresses and suggest conjectures about the asymptotic topology as the number of disks tends to infinity.

  12. HXMT satellite for space hard X-ray observation

    Wu, Y.; Ren, D.; You, Z.

    Space hard X-ray in the energy band from 10Kev to 250KeV is very important to the research of high energy astrophysical processes, especially some of the fundamental problems in astrophysics. Due to imaging difficulty in the hard X-ray band, Observations made over this band is comparatively less than other bands such as soft X-ray and gamma -ray. Up to now, there has been no hard X ray all sky- survey of high sensitivity. Based on the Direct Demodulation imaging method recently developed, the Hard X- ray Modulation Telescope(HXMT) mission is proposed under the Major State Basic Research Development Program of China. The scientific objective of HXMT mission is to realize the first hard X-ray all sky survey of high sensitivy and angular resolution in the world, and to present the first detailed sky map of hard X r a y - distribution. In this article, the physical basis, the imaging principle and the basic structure of HXMT are briefly introduced. The expected angular resolution of observation and position accuracy of radiant source are 2' and 0.2' respectively. Based on the analysis of the mission requirement of HXMT, the mission design of HXMT satellite is presented in which the concept of integrative design approach is presented and implemented. The design of spacecraft subsystems such as strcuture,C&DH and energy are also introduced. To meet the high precision demand of the attitude determination of HXMT, a new Attitude Determination &Control Subsystem(ADCS) scheme is presented in which the Microminiature Inertial Measurement Unit(MIMU) is employed as one of the key attitude sensors. Combined with star tracker, the expected attitude measurement accuracy is 0.01° in the normal mission mode. Based on all these thoughts, the ADCS is analyzed and its general design is presented in the paper. As the first chinese space hard X-ray observatory, the design approach of HXMT satellite is also helpful for other space exploration missions such as solar activity inspection

  13. Active Vibration Control of a Microactuator for the Hard Disk Drive Using Self-Sensing Actuation

    Minoru Sasaki


    Full Text Available This paper presents the self-sensing control of a microactuator for hard disk drives. The microactuator uses a PZT actuator pair installed on the suspension assembly. The self-sensing microactuator forms a combined sensing and actuation mechanism. Direct velocity feedback and positive position feedback are used in this paper. Our experimental results show that both strategies are effective in suppressing vibrational modes and successfully demonstrate the feasibility of using a self-sensing actuator on an HDD suspension assembly.

  14. Simple spark erosion device based on optical disk or hard disk drive actuators.

    Kamer, O


    We present the design of a compact electric discharge device incorporating hard disk or optical disk drive actuators. It is simple enough to be assembled in the absence of a mechanical workshop. The electronic circuit allows the adjustment of current, voltage, and discharge power. The system has been tested with organic dielectric liquids and deionized water and spark conditions; dynamic properties and machining characteristics were investigated. This device can be used to shape materials or to produce powdered samples with low material loss and minimal liquid consumption.

  15. Hard disk drive based microsecond x-ray chopper for characterization of ionization chambers and photodiodes

    Müller, O.; Lützenkirchen-Hecht, D.; Frahm, R.


    A fast X-ray chopper capable of producing ms long X-ray pulses with a typical rise time of few μs was realized. It is ideally suited to investigate the temporal response of X-ray detectors with response times of the order of μs to ms, in particular, any kind of ionization chambers and large area photo diodes. The drive mechanism consists of a brushless DC motor and driver electronics from a common hard disk drive, keeping the cost at an absolute minimum. Due to its simple construction and small dimensions, this chopper operates at home lab based X-ray tubes and synchrotron radiation sources as well. The dynamics of the most important detectors used in time resolved X-ray absorption spectroscopy, namely, ionization chambers and Passivated Implanted Planar Silicon photodiodes, were investigated in detail. The results emphasize the applicability of this X-ray chopper.

  16. An Electrostatic Microactuator for Positioning a Hard-Disk Drive Magnetic Head

    Yoshino, Tomonori; Toshiyoshi, Hiroshi; Mita, Makoto; Kobayashi, Dai; Fujita, Hiroyuki

    We have newly developed a prototype model of silicon microfabricated piggyback actuator for positioning a read/write head of magnetic hard-disk drive, which is usually referred to as a dual servo system because the piggyback actuator for fine control is used in collaboration with the voice-coil motor for coarse control. The actuator is made of a 50-micron-thick SOI (silicon on insulator) wafer processed by deep RIE (reactive ion etching) of high-aspect ratio. Actuation mechanism is based upon electrostatic force generated by multiple parallel plates. Maximum displacement of 0.2μ with a dc driving voltage of 20V has been achieved with a 1mm × 0.3mm actuator of its resonance at 25kHz. An analytical model for predicting electromechanical performance has also been developed.

  17. Hard disk drive based microsecond x-ray chopper for characterization of ionization chambers and photodiodes

    Müller, O., E-mail:; Lützenkirchen-Hecht, D.; Frahm, R. [Bergische Universität Wuppertal, Gaußstraße 20, Wuppertal 42119 (Germany)


    A fast X-ray chopper capable of producing ms long X-ray pulses with a typical rise time of few μs was realized. It is ideally suited to investigate the temporal response of X-ray detectors with response times of the order of μs to ms, in particular, any kind of ionization chambers and large area photo diodes. The drive mechanism consists of a brushless DC motor and driver electronics from a common hard disk drive, keeping the cost at an absolute minimum. Due to its simple construction and small dimensions, this chopper operates at home lab based X-ray tubes and synchrotron radiation sources as well. The dynamics of the most important detectors used in time resolved X-ray absorption spectroscopy, namely, ionization chambers and Passivated Implanted Planar Silicon photodiodes, were investigated in detail. The results emphasize the applicability of this X-ray chopper.

  18. Extreme Radiation Hardness and Space Qualification of AlGaN Optoelectronic Devices

    Sun, Ke-Xun; Balakrishnan, Kathik; Hultgren, Eric; Goebel, John; Bilenko, Yuri; Yang, Jinwei; Sun, Wenhong; Shatalov, Max; Hu, Xuhong


    Unprecedented radiation hardness and environment robustness are required in the new generation of high energy density physics (HEDP) experiments and deep space exploration. National Ignition Facility (NIF) break-even shots will have a neutron yield of 1015 or higher. The Europa Jupiter System Mission (EJSM) mission instruments will be irradiated with a total fluence of 1012 protons/cm2 during the space journey. In addition, large temperature variations and mechanical shocks are expected in these applications under extreme conditions. Hefty radiation and thermal shields are required for Si and GaAs based electronics and optoelectronics devices. However, for direct illumination and imaging applications, shielding is not a viable option. It is an urgent task to search for new semiconductor technologies and to develop radiation hard and environmentally robust optoelectronic devices. We will report on our latest systematic experimental studies on radiation hardness and space qualifications of AlGaN optoelectronic devices: Deep UV Light Emitting Diodes (DUV LEDs) and solarblind UV Photodiodes (PDs). For custom designed AlGaN DUV LEDs with a central emission wavelength of 255 nm, we have demonstrated its extreme radiation hardness up to 2x1012 protons/cm2 with 63.9 MeV proton beams. We have demonstrated an operation lifetime of over 26,000 hours in a nitrogen rich environment, and 23,000 hours of operation in vacuum without significant power drop and spectral shift. The DUV LEDs with multiple packaging styles have passed stringent space qualifications with 14 g random vibrations, and 21 cycles of 100K temperature cycles. The driving voltage, current, emission spectra and optical power (V-I-P) operation characteristics exhibited no significant changes after the space environmental tests. The DUV LEDs will be used for photoelectric charge management in space flights. For custom designed AlGaN UV photodiodes with a central response wavelength of 255 nm, we have demonstrated

  19. Digital Simulation of Space Vector Modulation Based Induction Motor Drive

    G.V. Siva Krishna Rao and T.S. Surendra


    Full Text Available This study deals with simulation of Space vector modulated inverter fed induction motor drive. The drive system is modeled using matlab simulink and the results are presented. This drive has advantages like reduced harmonics and heating. Fixed AC is converted into DC and this DC is converted into variable voltage and variable frequency AC using SVM inverter. The output of SVM is applied to the stator of induction motor. The simulation results are compared with the analytical results. The FFT analysis shows that the current spectrum has reduced harmonics compared to the conventional system.

  20. Neodymium as the main feature of permanent magnets from hard disk drives (HDDs).

    München, Daniel Dotto; Veit, Hugo Marcelo


    As a way to manage neodymium-iron-boron (NdFeB) magnets wasted in end-of-life hard disk drives (HDDs), a waste characterization is needed prior to a recycling process. Due to their magnetic properties, NdFeB magnets are essential in technological applications nowadays, thus causing an increase in the industrial demand for rare earth metals. However, these metals have a short supply, since they are difficult to obtain from ores, creating a critical market. In this work, a study of the characterization of sintered neodymium-iron-boron magnets was undertaken by qualitatively and quantitatively uncovering the neodymium recovery potential from this type of electronic waste. From the collection and disassembly of hard disk drives, in which the magnet represents less than 3% of the total weight, an efficient demagnetization process was proceeded at 320°C. Then, the magnet was ground and screened for an X-ray diffraction (XRD) analysis, which showed the Nd2Fe14B tetragonal phase as the dominant constituent of the sample. An analysis was also carried out in a scanning electron microscope (SEM) and an inductively coupled plasma optical emission spectrometer (ICP-OES), where the magnet composition showed 21.5wt% of neodymium and 65.1wt% of iron, among other chemicals. This Nd content is higher than the one found in Nd ores, enhancing the recyclability and the importance of waste management.

  1. Equipment to detect bad isolator in hard disk drive testing process

    Winai Tumthong


    Full Text Available With increasing data capacity of hard disk drive (HDD today, the testing time of a hard disk drive becames longer. It takes approximately 25 - 30 hours. Vibrations during HDD testing process significantly contribute to testing errors. Isolator and pocket slot were used to reduce the vibration. The physical property of isolators was charged, that led to the results of HDD testing. Because of the error, the testing process needs to be redone. As a result, the testing time is extended. This research developed a system to detect isolator function using “Ariduino Due” microcontroller along with “Micro-electromechanical System – MEMS” accelerator sensor. For the precise analysis, the statistical method called t test was used to group isolators by their functioning conditions. It was found that, the measured vibration amplitude in any direction canbe used as the criteria for identifying the isolator conditions. This detective system can determine the bad isolator at early stage before the exceeding vibration will affect the testing process.

  2. Recycling potential of neodymium: the case of computer hard disk drives.

    Sprecher, Benjamin; Kleijn, Rene; Kramer, Gert Jan


    Neodymium, one of the more critically scarce rare earth metals, is often used in sustainable technologies. In this study, we investigate the potential contribution of neodymium recycling to reducing scarcity in supply, with a case study on computer hard disk drives (HDDs). We first review the literature on neodymium production and recycling potential. From this review, we find that recycling of computer HDDs is currently the most feasible pathway toward large-scale recycling of neodymium, even though HDDs do not represent the largest application of neodymium. We then use a combination of dynamic modeling and empirical experiments to conclude that within the application of NdFeB magnets for HDDs, the potential for loop-closing is significant: up to 57% in 2017. However, compared to the total NdFeB production capacity, the recovery potential from HDDs is relatively small (in the 1-3% range). The distributed nature of neodymium poses a significant challenge for recycling of neodymium.

  3. Continuous quality inspection in hard disc drive manufacturing: A case study

    Yupa Lorkanchanakul


    Full Text Available This paper presents the continuous sampling plan CSP-100 that was developed from the continuous sampling plans CSP-1, CSP-4 and CSP-C. The objective of this paper is to apply the continuous sampling plan for the new CSP-100 plan proving a reduction in the delivery inspection time compared to the single lot sampling plan (SSP while maintaining the same or greater quality conformance. This CSP-100 was studied in Hard Disc Drive manufacturing. The parameters used in the CSP-100 plan are as follows; i (the number of consecutive conforming units, f (the sampling frequency of partial number in 100% inspected units and c (the acceptance number. CSP-100 computes four performance measures, Average Fraction Inspected (AFI, Average Outgoing Quality (AOQ, Lot Acceptance Rate (LAR and Defective Parts Per Million (DPPM. The advantage of this CSP-100 plan is not only to reduce the inspection time but also prove higher productivity numbers when compared with SSP. The verified results of using the CSP-100 plan proved a reduced inspection time of 6,722,702 minutes or 15% compared to SSP. CSP-100 also eliminates the work stations and transportation processes due to the inspection area and inspectors are no longer required. The Function Out of Box Audit (FOBA is introduced to monitor the CSP-100 performance. The FOBA audit results confirm that the CSP-100 maintains the same good quality level as the SSP. The excellent results of implementing the CSP-100 show a reduction in the inspection cost by 3,693,730.04 baht or 60.40% compared to SSP, as well as the additional cost savings by no longer needing to purchase a new tester; a savings of ~44 million baht. The CSP-100 plan also eliminates the issue of delayed delivery that is part of the SSP process. Moreover it is a better choice in inspecting the continuous quality process in Hard Disc Drive manufacturing.

  4. Dynamic characteristics of hard disk drive spindles supported by hydrodynamic bearings


    Most hard disk spindles currently used are supported by grease lubricated deep-groove ball bearings.However, in the trend of increasing spindle speed and reducing size and cost, the shortcomings of ball bearing spin-dles, such as high non-repeatable run out, high acoustic noise and short life time at high running speed, make themunsuitable for high performance hard disk drives (HDD). On the contrary, the dynamic characteristics of hydrody-namic bearing spindles are superior to that of ball bearing spindles. Therefore, they are considered to be the substi-tute of ball bearing spindles in HDD. In this paper, a simulative setup of HDD is build up. The dynamic characteristicsof liquid lubricated spiral groove bearing(SGB) spindles are studied. The effects of both operating condition andbearing clearance are investigated. It is found that running speed of the spindle has significant influence on its dy-namic performance, while the load has little influence. The effect of clearance is also evident.

  5. A camera for imaging hard x-rays from suprathermal electrons during lower hybrid current drive on PBX-M

    von Goeler, S.; Kaita, R.; Bernabei, S.; Davis, W.; Fishman, H.; Gettelfinger, G.; Ignat, D.; Roney, P.; Stevens, J.; Stodiek, W. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Jones, S.; Paoletti, F. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center); Petravich, G. (Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics); Rimini,


    During lower hybrid current drive (LHCD), suprathermal electrons are generated that emit hard X-ray bremsstrahlung. A pinhole camera has been installed on the PBX-M tokamak that records 128 [times] 128 pixel images of the bremsstrahlung with a 3 ms time resolution. This camera has identified hollow radiation profiles on PBX-M, indicating off-axis current drive. The detector is a 9in. dia. intensifier. A detailed account of the construction of the Hard X-ray Camera, its operation, and its performance is given.

  6. CZT in Space Based Hard-X-ray Astronomy

    Garson, A; Weidenspointner, G; Novikova, E I; Grindlay, J; Hong, J; Jung, I V


    One of the key aspects of a detector material for space-borne hard X-ray and gamma-ray telescopes is the rate of prompt and delayed background events generated inside the material by charged and neutral particles striking the detector. These particles are Cosmic Rays, particles trapped in Earth's magnetic field, and secondaries from Cosmic Ray interacting with the atmosphere and the spacecraft. Here, we present a preliminary study of Cadmium Zinc Telluride (CZT) and its behaviour in space environments. We have used the simulation package MGGPOD to estimate the background of the CZT detectors in the proposed Energetic X-ray Imaging Survey Telescope (EXIST) for possible orbital parameters. The EXIST mission will make use of 6 square meters of 0.5 cm thick CZT detectors to record cosmic X-rays in the energy range from 10 keV to 600 keV. The detectors will be shielded by a fully or partly active shield. For the specific detector and shielding geometry considered here and an orbit with a low (7 deg) inclination, t...

  7. Impact of CMOS Scaling on Single-Event Hard Errors in Space Systems

    Johnston, A. H.; Swift, G. M.; Shaw, D. C.


    Applications of highly scaled devices in space applications are shown to be limited by hard errors from cosmic rays. Hard errors were first observed in 0.8 (micro)m DRAMs. For feature sizes below 0.5 (micro)m, scaling theory predicts that low power devices will have much lower hard error rates than devices optimized for high speed.


    Zhou Haomiao; Wang Jie; Zhou Youhe; Zheng Xiaojing


    Based on generalized the variation method, by introducing Hamilton function and Lagrange multiplier, this paper proposed a linear quadratic optimal control strategy for an incomplete controllable system with fixed terminal state and time. Applying the proposed optimal control to the simple two-input dual-stage actuator magnetic head positioning system with three degrees-of-freedom, the simulation results show that the system has no residual vibration at the terminal position and time, which can reduce the total access time during head positioning process.To verify the validation of the optimal control strategy of three degrees-of-freedom spring-mass models in actual magnetic head positioning of hard disk drives, a finite element model of an actual magnetic head positioning system is presented. Substituting the optimal control force from simple three degrees-of-freedom spring-mass models into the finite element model, the simulation results show that the magnetic head also has no residual vibration at the end of track-to-track travel.That is to say, the linear quadratic optimal control technique based on simple two-input dualstage actuator system with three degrees-of-freedom proposed in this paper is of high reliability for the industrial application of an actual magnetic head positioning system.

  9. Economic Assessment for Recycling Critical Metals From Hard Disk Drives Using a Comprehensive Recovery Process

    Nguyen, Ruby Thuy; Diaz, Luis A.; Imholte, D. Devin; Lister, Tedd E.


    Since the 2011 price spike of rare earth elements (REEs), research on permanent magnet recycling has blossomed globally in an attempt to reduce future REE criticality. Hard disk drives (HDDs) have emerged as one feasible feedstock for recovering valuable REEs such as praseodymium, neodymium, and dysprosium. Nevertheless, current processes for recycling electronic waste only focus on certain metals as a result of feedstock and metal price uncertainties. In addition, there is a perception that recycling REEs is unprofitable. To shed some light on the economic viability of REE recycling from U.S. HDDs, this article combines techno-economic information of an electro-hydrometallurgical process with end-of-life HDD availability in a simulation model. The results showed that adding REE recovery to an HDD base and precious metal recovery process was profitable given current prices. Recovered REEs from U.S. HDDs could meet up to 5.2% rest-of-world (excluding China) neodymium magnet demand. Feedstock, aluminum, and gold prices are key factors to recycling profitability. REEs contributed 13% to the co-recycling profit.

  10. Quality control in hard disc drive manufacturing using pattern recognition technique

    Masood, Ibrahim; Shyen, Victor Bee Ee


    Computerized monitoring-diagnosis is an efficient technique to identify the source of unnatural variation (UV) in manufacturing process. In this study, a pattern recognition scheme (PRS) for monitoring-diagnosis the UVs was developed based on control chart pattern recognition technique. This PRS integrates the multivariate exponentially weighted moving average (MEWMA) control chart and artificial neural network (ANN) recognizer to perform two-stage monitoring-diagnosis. The first stage monitoring was performed using the MEWMA statistics, whereas the second stage monitoring-diagnosis was performed using an ANN. The PRS was designed based on bivariate process mean shifts between 0.75σ and 3.00σ, with cross correlation between ρ=0.1 and 0.9. The performance of the proposed PRS has been validated in quality control of hard disk drive component manufacturing. The validation proved that it is efficient in rapidly detecting UV and accurately classify the source of UV patterns. In a nutshell, the PRS will aid in realizing automated decision making system in manufacturing industry.

  11. Space lubrication and performance of harmonic drive gears

    Schafer, I.; Bourlier, P.; Hantschack, F.; Roberts, E. W.; Lewis, S. D.; Forster, D. J.; John, C.


    Harmonic Drive gears are commonly used in space mechanisms. However, lubrication is a critical aspect for proper, effective performance. This paper describes the principle of operation, explains the key parameters that define gear performance and discusses the nature of the various tribological interfaces to be found within HD gears and which call for effective lubrication. Test data are presented on a compact type of harmonic Drive, type CSD 20, that has a reduction ratio of 160:1. Two such HD gears have been lubricated with two space greases namely Maplub SH050a (a grease containing Nye 2001 oil and PTFE) and Maplub PF100a (a grease containing Z25 oil and PTFE). These units have been subjected to thermal-vacuum testing during which measurements were made of input torque, efficiency, break-out torque and no-load backdriving torque. The dependency of these parameters on output load, rotational speed and temperature have been quantified. The work identifies the interface between the wave generator's outer race and the inside surface of the flexspline as the most tribologically demanding and highlights the importance of achieving effective lubrication in this area.

  12. Building a Portable Computer Lab with Bootable USB Hard Drives Using Virtualisation

    Hao Shi


    Full Text Available Centralization of services is a global trend in universities worldwide. IT services in a university become asolo department to provide common IT support for the entire university community such as staff, studentsand visitors. Special services required for Computer Science and Information Technology courses are quiteoften not part of IT service agreements. The shared common computer labs are tightly controlled by ITservices and could not be used to deliver some specialised course such as Microsoft Active DirectoryConfiguration and Management. A dedicated computer lab is no longer a viable option to provide apractical solution with three-year University leased computers. The challenge in providing a long-termsolution heavily relies on the individual academic staffs who deliver such courses. There is an urgent needto find a new long-term working solution for this problem. After numerous search and research in findingan optimal solution, a portable computer lab using virtualisation is proposed. Instead of using a desktopcomputer in a common lab, each student enrolled in the course such as Microsoft Active Directory isallocated a customised USB hard dive. The USB drive contains a bootable Windows 7 Operating System aswell as six Windows Servers operated under Microsoft Windows Virtual PC. This not only allows thestudents to use a common computer lab but also enable them to totally control their learning with flexibilitywhich was not achievable in the past. This paper aims to share the knowledge as well as tricks and tipsgained through the process and to provide step by step instructions for building the customised USB harddive. It is expected that the concept of a ‘portable’ computer lab using virtualisation will provide insightinto delivery of IT courses in the future.

  13. A Decision Framework for Location Selection in Thailand: A Case Study in Hard Disk Drive Manufacturing Facility Location

    Bhumipipatana, Kanitsaran


    ABSTRACT Making location selection for the operation of products is a complex decision-making process for manufacturing firms since the optimal location could enhance the firms’ competitive advantage and lead to a success in business. In this study, the critical factors affecting foreign firms’ international location decision are explored and aggregated into a comprehensive set of main factors and sub-factors. The results are examined by looking at the group sample of the Hard Disk Drive ...

  14. Does hard insertion and space improve shock absorption ability of mouthguard?

    Takeda, Tomotaka; Ishigami, Keiichi; Handa, Jun; Naitoh, Kaoru; Kurokawa, Katsuhide; Shibusawa, Mami; Nakajima, Kazunori; Kawamura, Shintaro


    Mouthguards are expected to reduce sports-related orofacial injuries. Numerous studies have been conduced to improve the shock absorption ability of mouthguards using air cells, sorbothane, metal wire, or hard material insertion. Most of these were shown to be effective; however, the result of each study has not been applied to clinical use. The aim of this study was to develop mouthguards that have sufficient prevention ability and ease of clinical application with focus on a hard insertion and space. Ethylene vinyl acetate (EVA) mouthguard blank used was Drufosoft and the acrylic resin was Biolon (Dreve-Dentamid GMBH, Unna, Germany). Three types of mouthguard samples tested were constructed by means of a Dreve Drufomat (Type SO, Dreve-Dentamid) air pressure machine: the first was a conventional laminated type of EVA mouthguard material; the second was a three layer type with acrylic resin inner layer (hard-insertion); the third was the same as the second but with space that does not come into contact with tooth surfaces (hard + space). As a control, without any mouthguard condition (NOMG) was measured. A pendulum type impact testing machine with interchangeable impact object (steel ball and baseball) and dental study model (D17FE-NC.7PS, Nissin, Tokyo, Japan) with the strain gages (KFG-1-120-D171-11N30C2: Kyowa, Tokyo, Japan) applied to teeth and the accelerometer to the dentition (AS-A YG-2768 100G, Kyowa) were used to measure transmitted forces. Statistical analysis (anova, P shock absorption ability of about 40% was shown with conventional EVA and hard-insertion and about 50% with hard + space. In a baseball that was softer compared with steel ball, a decrease rate is smaller, reduction (EVA = approximately 4%, hard-insertion = approximately 12%, hard + space = approximately 25%) was admitted in the similar order. A significant difference was found with all the combinations except for between EVA and hard-insertion with steel ball (Tukey test). About

  15. Radiation Hard Space Wire Gigabit Ethernet Compatible Transponder Project

    National Aeronautics and Space Administration — Current and future programs of near-Earth and deep space exploration performed by NASA and Department of Defense require the development of reconfigurable,...

  16. Failure characterization at head/disk interface of hard disk drive


    The characterization of sub-micron features and particles between hard disk interface(HDI) is becoming even more important to the hard disk industry in the fields of corrosion, tribologyand the contamination. In this paper, media scratch and particles are characterized with AES,TOF-SIMS, SEM/EDX and LPC. The main causes resulted in serious media scratch have beenanalyzed and discussed.

  17. On the Future of Head-Based Microactuators in Hard Disk Drives

    Wernow, Josiah Natan

    Dual-stage actuation is an important technology enabler for advancing hard disk drive capacity and performance. This thesis describes the ongoing trend of decreasing track pitches required for areal density growth and increasing disturbances arising from rising spindle speeds, demonstrating that future dual-stage actuators will need to overcome the bandwidth limitations faced by the current suspension-based devices. First, the state of the art for dual-stage actuation is presented in the form of a literature review. This is followed by an overview of a new servo-mechanical design and analysis technique which is a hybrid of Galerkin beam elements and optimal linear quadratic Gaussian control analysis. This new technique is used to demonstrate the potential performance benefits of head-based actuation over suspension-based actuation. With the driving goal of designing a new head-based actuator, the constraints posed by industry are presented and discussed in detail. This is followed by an overview of the various actuation mechanisms evaluated, including several electrostatic and piezoelectric devices. The two most significant challenges identified through this analysis are the introduction of a gap at the trailing edge of the air-bearing and the necessity to actuate traces with sufficiently high actuation force. A quasi-shear mode piezoelectric actuator is proposed as a cost-effective head-based actuator which meets the given criteria and can be implemented at the wafer-scale. A new prototype was fabricated at the Berkeley Nanofabrication Laboratory with a measured bandwidth above 50 kHz. Since the proposed head-based actuation scheme requires a gap in the air-bearing surface, a second actuation mode is also presented. It is shown that the gap width between the slider body and read/write head can be controlled independently of track-following displacement in order to minimize pressure loss at the air-bearing surface. It is also shown that the directionality along

  18. The simulation of hard x-ray images obtained during lower hybrid current drive on PBX-M

    Goeler, S. von; Fishman, H.; Ignat, D. [and others


    During lower hybrid current drive on PBX-M suprathermal electrons in the 30 to 150 keV range are generated. These electrons emit hard X-ray bremsstrahlung in collisions with plasma ions; the radiation creates images in a hard X-ray pinhole camera. In order to interpret the hard X-ray images, a computer simulation code has been written, the PBXRAY code. It represents an extension of the STEVENS code that calculates the free-free and free-bound radiation for non-Maxwellian relativistic electron tail distributions. The PBXRAY code provides the chord integration in the bean-shaped plasma geometry on PBX-M and integrates over photon energy. The simulations show that the location of the suprathermal electrons can be determined with an accuracy of approximately two centimeters in the plasma. In particular, the authors analyzed discharges whose characteristic ``hollow`` images indicate off-axis LH current drive. A comparison of images taken with different absorber foils reveals that the suprathermal electrons have less than 150 keV parallel energy for the hollow discharges.

  19. Radiation Hard Space Wire Gigabit Ethernet Compatible Transponder Project

    National Aeronautics and Space Administration — High-bandwidth, Radiation Hardening, low-power, low-EMI, easily reconfigurable and upgradeable transponder-based interconnects between processor nodes, subsystems,...

  20. Trade Space Study for the Performance of Hard Armor Versus Threat Striking Velocity at Range


    TECHNICAL REPORT AD ________________ NATICK/TR-15/025 TRADE SPACE STUDY FOR...official Department of the Army position unless so designated by other authorized documents. Citation of trade names in this report does not...September 2013 – September 2014 4. TITLE AND SUBTITLE TRADE SPACE STUDY FOR THE PERFORMANCE OF HARD ARMOR VERSUS THREAT STRIKING VELOCITY AT RANGE 5a

  1. Towards Practical Whitebox Cryptography: Optimizing Efficiency and Space Hardness

    Bogdanov, Andrey; Isobe, Takanori; Tischhauser, Elmar Wolfgang


    Whitebox cryptography aims to provide security for cryptographic algorithms in an untrusted environment where the adversary has full access to their implementation. Typical security goals for whitebox cryptography include key extraction security and decomposition security: Indeed, it should...... such as DES or AES are prone to practical key extraction attacks, there have been two dedicated design approaches for whitebox block ciphers: ASASA by Birykov et al. at ASIACRYPT'14 and SPACE by Bogdanov and Isobe at CCS'15. While ASASA suffers from decomposition attacks, SPACE reduces the security against...... key extraction and decomposition attacks in the white box to the security of a standard block cipher such as AES in the standard blackbox setting. However, due to the security-prioritized design strategy, SPACE imposes a sometimes prohibitive performance overhead in the real world as it needs many AES...

  2. The Relativistic Boltzmann Equation on Bianchi Type I Space Time for Hard Potentials

    Noutchegueme, Norbert; Takou, Etienne; Tchuengue, E. Kamdem


    In this paper, we consider the Cauchy problem for the spatially homogeneous relativistic Boltzmann equation with small initial data. The collision kernel considered here is for a hard potentials case. The background space-time in which the study is done is the Bianchi type I space-time. Under certain conditions made on the scattering kernel and on the metric, a uniqueness global (in time) solution is obtained in a suitable weighted functional space.

  3. Benchmark Study and Characterization of European Rad-Hard Power MOSFEts for Space Applications

    Becherer, J.; Dittrich, R.; Muschitiello, M.; Constantino, A.


    Power Field Effect Transistors are an integral part of the electronic equipment of every space vehicle. In order to survive the harsh conditions of space, the transistors have to fulfill rigorous conditions. A number one in the list of space qualification criteria is the guarantee of radiation hardness. Today several radiation hard Power MOSFETs are available from a variety of companies all over the world. A benchmark study of the available Power MOSFETs for space applications has been compiled in this paper. The newly developed European Superjunction Technologies Power MOSFETs from Infineon show the best performance. Therefore, a total ionizing dose characterization of the 250 V and 150 V European MOSFETs have been performed.

  4. Aerodynamic map for soft and hard hypersonic level flight in near space

    Ruifeng Hu; Ziniu Wu; Zhe Wu; Xiaoxin Wang; Zhongwei Tian


    In this note, we design a velocity-altitude map for hypersonic level flight in near space of altitude 20-100 km. This map displays aerodynamic-related parameters associated with near space level flight, schematically or quantitatively. Various physical conditions for the near-space level flight are then characterized, including laminar or turbulent flow, rarefaction or continuous flow, aerodynamic heating, as well as conditions for sustaining level flight with and without orbital effect. This map allows one to identify conditions to have soft flight or hard flight, and this identification would be helpful for making correct planning on detailed studies of aerodynamics or making initial design of near space vehicles.

  5. An adaptive method of averaging the space-vectors location in DSP controlled drives

    Debowski, A.; Chudzik, P. [Technical University of Lodz, Institute of Automatic Control, Lodz (Poland)


    In the paper a practical method of averaging the space- vector location for electrical drives controlled with digital signal processors (DSP) is demonstrated. This method enables to approximate the step movement of the given real space-vector with a smooth rotation of a conventional one in given time subintervals by any field rotation speed. The method is suitable for many practical applications in vector controlled electrical drives. In the paper some experimental examples of estimation the space-vectors of stator current and rotor flux in an inverter-fed induction motor drive are shown. (orig.)

  6. A dusty box (or hard drive) of photos: Where’s the critical engagement?

    Markham, Annette; Strosneider, Luke

    , as a series of thematically related images, etc.– but many advocate the practice of creating image sequences. A “sequence” can be thought of as a form of visual storytelling in which the photographer relates his/her experience of an urban space by photographing scenes that offer personal resonance...... individually and collectively negotiate and construct potentially transformative understandings of familiar urban spaces as well as their relationships to and roles within such spaces. This paper discusses photography as participatory critical engagement and (potentially) provides an experiential exercise...... for other conference participants. We aim to explore what happens after people engage in the physical act of making a photo in context, which may have importance for the archiving of Aarhus as the European Capital of Culture in 2017. Photographs can be considered in a variety of ways – as individual images...

  7. Driving a hard bargain: sex ratio and male marriage success in a historical US population.

    Pollet, Thomas V; Nettle, Daniel


    Evolutionary psychologists have documented a widespread female preference for men of high status and resources, and evidence from several populations suggests that this preference has real effects on marriage success. Here, we show that in the US population of 1910, socioeconomic status (SES) had a positive effect on men's chances of marrying. We also test a further prediction from the biological markets theory, namely that where the local sex ratio produces an oversupply of men, women will be able to drive a harder bargain. As the sex ratio of the states increases, the effect of SES on marriage success becomes stronger, indicating increased competition between men and an increased ability to choose on the part of women.

  8. A simple method to prevent hard X-ray-induced preheating effects inside the cone tip in indirect-drive fast ignition implosions

    Liu, Dongxiao; Shan, Lianqiang; Zhou, Weimin; Wu, Yuchi; Zhu, Bin; Zhang, Feng; Bi, Bi; Zhang, Bo; Zhang, Zhimeng; Shui, Min; He, Yingling; Gu, Yuqiu, E-mail:; Zhang, Baohan [Science and Technology on Plasma Physics Laboratory, China Academy of Engineering Physics, Mianyang 621900 (China); Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Peng, Xiaoshi; Xu, Tao; Wang, Feng; Yang, Zhiwen; Chen, Tao; Chen, Li; Chen, Ming [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); and others


    During fast-ignition implosions, preheating of inside the cone tip caused by hard X-rays can strongly affect the generation and transport of hot electrons in the cone. Although indirect-drive implosions have a higher implosion symmetry, they cause stronger preheating effects than direct-drive implosions. To control the preheating of the cone tip, we propose the use of indirect-drive fast-ignition targets with thicker tips. Experiments carried out at the ShenGuang-III prototype laser facility confirmed that thicker tips are effective for controlling preheating. Moreover, these results were consistent with those of 1D radiation hydrodynamic simulations.

  9. Tracking the Flow of Resources in Electronic Waste - The Case of End-of-Life Computer Hard Disk Drives.

    Habib, Komal; Parajuly, Keshav; Wenzel, Henrik


    Recovery of resources, in particular, metals, from waste flows is widely seen as a prioritized option to reduce their potential supply constraints in the future. The current waste electrical and electronic equipment (WEEE) treatment system is more focused on bulk metals, where the recycling rate of specialty metals, such as rare earths, is negligible compared to their increasing use in modern products, such as electronics. This study investigates the challenges in recovering these resources in the existing WEEE treatment system. It is illustrated by following the material flows of resources in a conventional WEEE treatment plant in Denmark. Computer hard disk drives (HDDs) containing neodymium-iron-boron (NdFeB) magnets were selected as the case product for this experiment. The resulting output fractions were tracked until their final treatment in order to estimate the recovery potential of rare earth elements (REEs) and other resources contained in HDDs. The results further show that out of the 244 kg of HDDs treated, 212 kg comprising mainly of aluminum and steel can be finally recovered from the metallurgic process. The results further demonstrate the complete loss of REEs in the existing shredding-based WEEE treatment processes. Dismantling and separate processing of NdFeB magnets from their end-use products can be a more preferred option over shredding. However, it remains a technological and logistic challenge for the existing system.

  10. Operations Data Files, driving force behind International Space Station operations

    Hoppenbrouwers, Tom; Ferra, Lionel; Markus, Michael; Wolff, Mikael


    Almost all tasks performed by the astronauts on-board the International Space Station (ISS) and by ground controllers in Mission Control Centre, from operation and maintenance of station systems to the execution of scientific experiments or high risk visiting vehicles docking manoeuvres, would not be possible without Operations Data Files (ODF). ODFs are the User Manuals of the Space Station and have multiple faces, going from traditional step-by-step procedures, scripts, cue cards, over displays, to software which guides the crew through the execution of certain tasks. Those key operational documents are standardized as they are used on-board the Space Station by an international crew constantly changing every 3 months. Furthermore this harmonization effort is paramount for consistency as the crew moves from one element to another in a matter of seconds, and from one activity to another. On ground, a significant large group of experts from all International Partners drafts, prepares reviews and approves on a daily basis all Operations Data Files, ensuring their timely availability on-board the ISS for all activities. Unavailability of these operational documents will halt the conduct of experiments or cancel milestone events. This paper will give an insight in the ground preparation work for the ODFs (with a focus on ESA ODF processes) and will present an overview on ODF formats and their usage within the ISS environment today and show how vital they are. Furthermore the focus will be on the recently implemented ODF features, which significantly ease the use of this documentation and improve the efficiency of the astronauts performing the tasks. Examples are short video demonstrations, interactive 3D animations, Execute Tailored Procedures (XTP-versions), tablet products, etc.

  11. Space Vector Based Generalized Dpwm Algorithms for Vsi Fed Induction Motor Drive

    N. Praveena


    Full Text Available This paper presents Space Vector based Generalized DiscontinuousPulse width modulation (GDPWM algorithms for VSI fed Induction motor drive. To avoid the complexity due to angle calculation and sector identification involved in Conventional space vector pulse width modulation (CSVPWM. The Proposed algorithms use the concept of Imaginary Switching times and a constant variable µ and modulation phase angle δ are used to generate modulating waveforms.The proposed algorithms results in reduced current ripple over CSVPWM. To validate the proposed methods, simulation is carried on V/f controlled Induction Motor drive in MATLAB/SIMULINK environment and the results are discussed.

  12. A comparative approach for the investigation of biological information processing: An examination of the structure and function of computer hard drives and DNA

    D'Onofrio David J


    Full Text Available Abstract Background The robust storage, updating and utilization of information are necessary for the maintenance and perpetuation of dynamic systems. These systems can exist as constructs of metal-oxide semiconductors and silicon, as in a digital computer, or in the "wetware" of organic compounds, proteins and nucleic acids that make up biological organisms. We propose that there are essential functional properties of centralized information-processing systems; for digital computers these properties reside in the computer's hard drive, and for eukaryotic cells they are manifest in the DNA and associated structures. Methods Presented herein is a descriptive framework that compares DNA and its associated proteins and sub-nuclear structure with the structure and function of the computer hard drive. We identify four essential properties of information for a centralized storage and processing system: (1 orthogonal uniqueness, (2 low level formatting, (3 high level formatting and (4 translation of stored to usable form. The corresponding aspects of the DNA complex and a computer hard drive are categorized using this classification. This is intended to demonstrate a functional equivalence between the components of the two systems, and thus the systems themselves. Results Both the DNA complex and the computer hard drive contain components that fulfill the essential properties of a centralized information storage and processing system. The functional equivalence of these components provides insight into both the design process of engineered systems and the evolved solutions addressing similar system requirements. However, there are points where the comparison breaks down, particularly when there are externally imposed information-organizing structures on the computer hard drive. A specific example of this is the imposition of the File Allocation Table (FAT during high level formatting of the computer hard drive and the subsequent loading of an operating

  13. SuperAGILE: the hard X-ray Imager for the AGILE space mission

    Feroci, M; Soffitta, P; Del Monte, E; Di Persio, G; Donnarumma, I; Evangelista, Y; Frutti, M; Lapshov, I; Lazzarotto, F; Mastropietro, M; Morelli, E; Pacciani, L; Porrovecchio, G; Rapisarda, M; Rubini, A; Tavani, M; Argan, A


    SuperAGILE is a coded mask experiment based on silicon microstrip detectors. It operates in the 15-45 keV nominal energy range, providing crossed one-dimensional images of the X-ray sky with an on-axis angular resolution of 6 arcmin, over a field of view in excess of 1 steradian. It was designed as the hard X-ray monitor of the AGILE space mission, a small satellite of the Italian Space Agency devoted to image the gamma-ray sky in the 30 MeV - 50 GeV energy band. The AGILE mission was launched in a low-earth orbit on 23^{rd} April 2007. In this paper we describe the SuperAGILE experiment, its construction and test processes, and its performance before flight, based on the on-ground test and calibrations.

  14. Controller Design for Direct Torque Controlled Space Vector Modulated (DTC-SVM) Induction Motor Drives

    Zelechowski, M.; Kazmierkowski, M.P.; Blaabjerg, Frede


    In this paper two different methods of PI controllers for direct torque controlled-space vector modulated induction motor drives have been studied. The first one is simple method based only on symmetric optimum criterion. The second approach takes into account the full model of induction motor in...

  15. Hybrid Asymmetric Space Vector Modulation for inverter based direct torque control induction motor drive

    Nandakumar Sundararaju


    Full Text Available This paper proposes novel hybrid asymmetric space vector modulation technique for inverter operated direct torque control induction motor drive. The hybridization process is performed by the combination of continuous asymmetric space vector modulation pulse width technique (ASVPWM and fuzzy operated discontinuous ASVPWM technique. Combination process is based on pulse mismatching technique. Pulse mismatching technique helps to reduce the active region of the switch. Finally, optimal pulses are applied to control the inverter. The optimal hybrid pulse condense switching losses of the inverter and also improves the operating performance of the direct torque control (DTC based drive system like smooth dynamic response in speed reversal, minimum torque error, settling time of speed. Simulation results of proposed hybrid asymmetric space vector pulse width modulation technique to direct torque control (HASVPWM-DTC approach has been carried out by using Matlab-Simulink environment.

  16. Applications of Robust, Radiation Hard AlGaN Optoelectronic Devices in Space Exploration and High Energy Density Physics

    Sun, K.


    This slide show presents: space exploration applications; high energy density physics applications; UV LED and photodiode radiation hardness; UV LED and photodiode space qualification; UV LED AC charge management; and UV LED satellite payload instruments. A UV LED satellite will be launched 2nd half 2012.

  17. Human-Robot Teaming: From Space Robotics to Self-Driving Cars

    Fong, Terry


    In this talk, I describe how NASA Ames has been developing and testing robots for space exploration. In our research, we have focused on studying how human-robot teams can increase the performance, reduce the cost, and increase the success of space missions. A key tenet of our work is that humans and robots should support one another in order to compensate for limitations of manual control and autonomy. This principle has broad applicability beyond space exploration. Thus, I will conclude by discussing how we have worked with Nissan to apply our methods to self-driving cars, enabling humans to support autonomous vehicles operating in unpredictable and difficult situations.

  18. Impact of Radiation Hardness and Operating Temperatures of Silicon Carbide Electronics on Space Power System Mass

    Juhasz, Albert J.; Tew, Roy C.; Schwarze, Gene E.


    The effect of silicon carbide (SiC) electronics operating temperatures on Power Management and Distribution (PMAD), or Power Conditioning (PC), subsystem radiator size and mass requirements was evaluated for three power output levels (100 kW(e) , 1 MW(e), and 10 MW(e)) for near term technology ( i.e. 1500 K turbine inlet temperature) Closed Cycle Gas Turbine (CCGT) power systems with a High Temperature Gas Reactor (HTGR) heat source. The study was conducted for assumed PC radiator temperatures ranging from 370 to 845 K and for three scenarios of electrical energy to heat conversion levels which needed to be rejected to space by means of the PC radiator. In addition, during part of the study the radiation hardness of the PC electronics was varied at a fixed separation distance to estimate its effect on the mass of the instrument rated reactor shadow shield. With both the PC radiator and the conical shadow shield representing major components of the overall power system the influence of the above on total power system mass was also determined. As expected, results show that the greatest actual mass savings achieved by the use of SiC electronics occur with high capacity power systems. Moreover, raising the PC radiator temperature above 600 K yields only small additional system mass savings. The effect of increased radiation hardness on total system mass is to reduce system mass by virtue of lowering the shield mass.

  19. Measuring optical constants of multilayer materials for current and future hard X-ray space telescopes

    Brejnholt, Nicolai

    With the launch of the NuSTAR space telescope in 2012, a new era in X-ray astronomy began. NuSTAR provides astronomers unprecedented sensitivity in the hard X-ray band, operating from 6-79 keV through the use of multilayers. At lower energies, NuSTAR has an effective area comparable to previous missions, such as the XMM-Newton and Chandra. The overlap allows soft X-ray observations to be combined with hard X-ray ones, providing new constraints on theoretical models and allowing accurate determination of the properties of thermal and non-thermal processes. To successfully predict the performance of a hard X-ray multilayer telescope, precise knowledge of the optical properties of the constituent materials of the multilayers is required. Tungsten and platinum are the two high-density, high-Z materials in the NuSTAR multilayer systems, but early observations with NuSTAR showed that essential atomic parameters , i.e. the optical constants, of these materials are not correct. Specifically, there are significant residuals in spectral fits near the L absorption edges of both materials from 10-14 keV. This situation is not a surprise, as the optical constants for these materials are derived from tabulated photon-interaction cross sections, which does not properly capture the physics of the X-ray absorption fine structure (XAFS). As a result, the NuSTAR team is using an empirical correction to predict performance. The correction does not completely remove spectral features in the 10-14 keV region and is only good for weak sources. We propose to accurately measure the optical constants for tungsten and platinum in the hard X-ray region from 6-28.5 keV, replacing the empirical correction and providing a significant improvement to NuSTAR's response model. The improvement will be achieved by two independent and complementary routes to increase accuracy. One method relies on transmission measurements while the other utilizes reflection measurements. The proposing team leverages

  20. Performance of Magnetic-Superconductor Non-Contact Harmonic Drive for Cryogenic Space Applications

    Jose Luis Perez-Diaz


    Full Text Available Harmonic drives are profusely used in aerospace mainly because of their compactness and large reduction ratio. However, their use in cryogenic environments is still a challenge. Lubrication and fatigue are non-trivial issues under these conditions. The objective of the Magnetic-Superconductor Cryogenic Non-contact Harmonic Drive (MAGDRIVE project, funded by the EU Space FP7, is to design, build, and test a new concept of MAGDRIVE. Non-contact interactions among magnets, soft magnetic materials, and superconductors are efficiently used to provide a high reduction ratio gear that smoothly and naturally operates at cryogenic environments. The limiting elements of conventional harmonic drives (teeth, flexspline, and ball bearings are substituted by contactless mechanical components (magnetic gear and superconducting magnetic bearings. The absence of contact between moving parts prevents wear, lubricants are no longer required, and the operational lifetime is greatly increased. This is the first mechanical reducer in mechanical engineering history without any contact between moving parts. In this paper, the test results of a −1:20 inverse reduction ratio MAGDRIVE prototype are reported. In these tests, successful operation at 40 K and 10−3 Pa was demonstrated for more than 1.5 million input cycles. A maximum torque of 3 N·m and an efficiency of 80% were demonstrated. The maximum tested input speed was 3000 rpm, six times the previous existing record for harmonic drives at cryogenic temperatures.

  1. A proposed hardness assurance test methodology for bipolar linear circuits and devices in a space ionizing radiation environment

    Pease, R.L. [RLP Research, Albuquerque, NM (United States); Brown, D.B. [Naval Research Lab., Washington, DC (United States); Cohn, L. [Defense Special Weapons Agency, Alexandria, VA (United States)] [and others


    A hardness assurance test approach has been developed for bipolar linear circuits and devices in space. It consists of a screen for dose rate sensitivity and a characterization test method to develop the conditions for a lot acceptance test at high dose rate.

  2. Shortcuts to adiabaticity by counterdiabatic driving for trapped-ion displacement in phase space

    An, Shuoming; Lv, Dingshun; Del Campo, Adolfo; Kim, Kihwan


    The application of adiabatic protocols in quantum technologies is severely limited by environmental sources of noise and decoherence. Shortcuts to adiabaticity by counterdiabatic driving constitute a powerful alternative that speed up time-evolution while mimicking adiabatic dynamics. Here we report the experimental implementation of counterdiabatic driving in a continuous variable system, a shortcut to the adiabatic transport of a trapped ion in phase space. The resulting dynamics is equivalent to a `fast-motion video' of the adiabatic trajectory. The robustness of this protocol is shown to surpass that of competing schemes based on classical local controls and Fourier optimization methods. Our results demonstrate that shortcuts to adiabaticity provide a robust speedup of quantum protocols of wide applicability in quantum technologies.

  3. Radiation-Hard SpaceWire/Gigabit Ethernet-Compatible Transponder

    Katzman, Vladimir


    A radiation-hard transponder was developed utilizing submicron/nanotechnology from IBM. The device consumes low power and has a low fabrication cost. This device utilizes a Plug-and-Play concept, and can be integrated into intra-satellite networks, supporting SpaceWire and Gigabit Ethernet I/O. A space-qualified, 100-pin package also was developed, allowing space-qualified (class K) transponders to be delivered within a six-month time frame. The novel, optical, radiation-tolerant transponder was implemented as a standalone board, containing the transponder ASIC (application specific integrated circuit) and optical module, with an FPGA (field-programmable gate array) friendly parallel interface. It features improved radiation tolerance; high-data-rate, low-power consumption; and advanced functionality. The transponder utilizes a patented current mode logic library of radiation-hardened-by-architecture cells. The transponder was developed, fabricated, and radhard tested up to 1 MRad. It was fabricated using 90-nm CMOS (complementary metal oxide semiconductor) 9 SF process from IBM, and incorporates full BIT circuitry, allowing a loop back test. The low-speed parallel LVCMOS (lowvoltage complementary metal oxide semiconductor) bus is compatible with Actel FPGA. The output LVDS (low-voltage differential signaling) interface operates up to 1.5 Gb/s. Built-in CDR (clock-data recovery) circuitry provides robust synchronization and incorporates two alarm signals such as synch loss and signal loss. The ultra-linear peak detector scheme allows on-line control of the amplitude of the input signal. Power consumption is less than 300 mW. The developed transponder with a 1.25 Gb/s serial data rate incorporates a 10-to-1 serializer with an internal clock multiplication unit and a 10-1 deserializer with internal clock and data recovery block, which can operate with 8B10B encoded signals. Three loop-back test modes are provided to facilitate the built-in-test functionality. The

  4. Input Harmonic Analysis on the Slim DC-Link Drive Using Harmonic State Space Model

    Yang, Feng; Kwon, Jun Bum; Wang, Xiongfei


    the shortcomings of the present harmonic analysis methods, such as the time-domain simulation, or the Fourier analysis, this paper proposes a Harmonic State Space model to study the harmonics performance for this type of drive. In this study, this model is utilized to describe the behavior of the harmonic...... variation according to the switching instant, the harmonics at the steady-state condition, as well as the coupling between the multiple harmonic impedances. By using this model, the impaction on the harmonics performance by the film capacitor and the grid inductance is derived. Simulation and experimental...

  5. Robust PID Steering Control in Parameter Space for Highly Automated Driving

    Mümin Tolga Emirler


    Full Text Available This paper is on the design of a parameter space based robust PID steering controller. This controller is used for automated steering in automated path following of a midsized sedan. Linear and nonlinear models of this midsized sedan are presented in the paper. Experimental results are used to validate the longitudinal and lateral dynamic models of this vehicle. This paper is on automated steering control and concentrates on the lateral direction of motion. The linear model is used to design a PID steering controller in parameter space that satisfies D-stability. The PID steering controller that is designed is used in a simulation study to illustrate the effectiveness of the proposed method. Simulation results for a circular trajectory and for a curved trajectory are presented and discussed in detail. This study is part of a larger research effort aimed at implementing highly automated driving in a midsized sedan.


    Li, Amei


    Merged with duplicate record 10026.1/829 on 10.04.2017 by CS (TIS) Three readback signal detection methods are investigated for real-time flying height or head disk spacing variation measurement under vibration conditions. This is carried out by theoretical analysis, numerical simulation, and experimental study. The first method (amplitude detection) provides a simple way to study the head disk spacing change. The second method ( PW50 parameter estimation) can be used effective...

  7. A study on a micro-stepping drive system for space pointing platform

    Yang, Shuang; Li, Bao-quan; Zhang, Xin


    Along with the continuous development of the research in the space exploration field, the precision rotation control system is widely utilized in a lot of payloads of the satellites. It is stepping motor cooperating with reduction gear wheel to accomplish the precision rotation in some pointing platforms of the camera used in the satellite. By contrast with that, the approach of this paper could precisely control the rotation angle of the stepping motor without using reduction gear wheel. Therefore, the size and the height of the instrument would be reduced base on simplifying the structural design. Moreover, it reduces the cost to some extent. In this paper, it is adopted that the digital signal processor (DSP) controller and bipolar constant current motor drive circuit UC3717 to make a high performance, high subdivision, miniature control system come true, which is used to drive two-phase hybrid stepping motor. The methods are applied by the driver system that sine cosine micro stepping and constant current chopper drive with a fixed chopper period. The driver system also supplies the functions that involve subdivision selection, clockwise rotation or counter clockwise rotation control, and over current or over voltage or under voltage or overload protection, and so on. The description in this paper also includes the total schematic design, the approach to get current table in different subdivision levels, the current control method in hybrid stepping motor, the way to reduce electro- magnetic interference (EMI) of the hybrid stepping motor. And the total schematic design contains the DSP controller, the communication interface of the driver system, the design of power driving circuit, the interface circuit between the electrical sources, the constant current chopper drive circuit for the two-phase hybrid stepping motor. At last, it is verified by some experimental investigations that the control system not only has miniature size, simplified system design

  8. Easy fabrication of a new type of mouthguard incorporating a hard insert and space and offering improved shock absorption ability.

    Takeda, Tomotaka; Ishigami, Keiichi; Mishima, Osamu; Karasawa, Kensuke; Kurokawa, Katsuhide; Kajima, Takaki; Nakajima, Kazunori


    The positive effects of wearing a mouthguard have been indicated in various epidemiological surveys and experiments, and their usage appears to be increasing in many sports. However, many preventable sports-related dental injuries still occur even with the use of a conventional mouthguard. We have developed a mouthguard (the Hard & Space mouthguard) with sufficient injury prevention ability (more than 95% shock absorption ability against impact with a steel ball carrying 15.2 kg m(2) S(-2) potential energy) and ease of clinical application. This mouthguard consists of an outer and an inner EVA layer and a middle layer of acrylic resin (hard insert), with a space to prevent contact between the inner surface of the mouthguard and the buccal surfaces of the maxillary front teeth or teeth already weakened through prior damage or treatment. The purpose of this article is to describe the method by which the Hard & Space mouthguard may easily be fabricated. We believe that this new type of mouthguard has the potential to reduce sports-related dental injuries.

  9. Development of low-noise CCD drive electronics for the world space observatory ultraviolet spectrograph subsystem

    Salter, Mike; Clapp, Matthew; King, James; Morse, Tom; Mihalcea, Ionut; Waltham, Nick; Hayes-Thakore, Chris


    World Space Observatory Ultraviolet (WSO-UV) is a major Russian-led international collaboration to develop a large space-borne 1.7 m Ritchey-Chrétien telescope and instrumentation to study the universe at ultraviolet wavelengths between 115 nm and 320 nm, exceeding the current capabilities of ground-based instruments. The WSO Ultraviolet Spectrograph subsystem (WUVS) is led by the Institute of Astronomy of the Russian Academy of Sciences and consists of two high resolution spectrographs covering the Far-UV range of 115-176 nm and the Near-UV range of 174-310 nm, and a long-slit spectrograph covering the wavelength range of 115-305 nm. The custom-designed CCD sensors and cryostat assemblies are being provided by e2v technologies (UK). STFC RAL Space is providing the Camera Electronics Boxes (CEBs) which house the CCD drive electronics for each of the three WUVS channels. This paper presents the results of the detailed characterisation of the WUVS CCD drive electronics. The electronics include a novel high-performance video channel design that utilises Digital Correlated Double Sampling (DCDS) to enable low-noise readout of the CCD at a range of pixel frequencies, including a baseline requirement of less than 3 electrons rms readout noise for the combined CCD and electronics system at a readout rate of 50 kpixels/s. These results illustrate the performance of this new video architecture as part of a wider electronics sub-system that is designed for use in the space environment. In addition to the DCDS video channels, the CEB provides all the bias voltages and clocking waveforms required to operate the CCD and the system is fully programmable via a primary and redundant SpaceWire interface. The development of the CEB electronics design has undergone critical design review and the results presented were obtained using the engineering-grade electronics box. A variety of parameters and tests are included ranging from general system metrics, such as the power and mass

  10. A Review of Tribological Coatings for Control Drive Mechanisms in Space Reactors

    CJ Larkin; JD Edington; BJ Close


    Tribological coatings must provide lubrication for moving components of the control drive mechanism for a space reactor and prevent seizing due to friction or diffusion welding to provide highly reliable and precise control of reflector position over the mission lifetime. Several coatings were evaluated based on tribological performance at elevated temperatures and in ultrahigh vacuum environments. Candidates with proven performance in the anticipated environment are limited primarily to disulfide materials. Irradiation data for these coatings is nonexistent. Compatibility issues between coating materials and structural components may require the use of barrier layers between the solid lubricant and structural components to prevent deleterious interactions. It would be advisable to consider possible lubricant interactions prior to down-selection of structural materials. A battery of tests was proposed to provide the necessary data for eventual solid lubricant/coating selection.

  11. High Performance Direct Torque Control of Induction Motor Drives Using Space Vector Modulation

    S. Allirani


    Full Text Available This paper presents a simple approach to design and implement Direct Torque Control technique for voltage source inverter fed induction motor drives. The direct torque control is one of the excellent strategies available for torque control of induction machine. It is considered as an alternative to field oriented control technique. The Direct Torque Control scheme is characterized by the absence of PI regulators, co-ordinate transformations, current regulators and pulse width modulated signal generators. Direct Torque Control allows a good torque control in steady state and transient operating conditions. The direct torque control technique based on space vector modulation and switching table has been developed and presented in this paper.


    Husnija Hasanbegović


    Full Text Available This study investigates knowledge on use of body extremities and body in space by children who are deaf or hard-of-hearing. A random sample of 60 participants was used in the study, with chronological age of 6 to 8 years. Experimental group of 30 participants involved pupils who are deaf or hard-of-hearing both male and female who attend school in Sarajevo (Bosnia and Herzegovina. Control group of 30 participants involved pupils who are typically hearing both male and female who were chronologically matched to the participants in the experimental group. Measuring instruments were created for the purpose of extracting quantitative data analysis, scaled from 1 to 5 units of measurement. The results are showed significant differences between children who are deaf or hard-of-hearing and children who are typically hearing (F=23, 08 p=0.00. The children who are deaf or hard-of-hearing showed significantly weaker knowledge of perception of body movements.

  13. Lightweight, Space and Power Efficient Solar Array Drive Design Implemented within Remote Interface Unit

    Kivikyto, Tatu; Laaksoen, Jyrki


    PATRIA has implemented highly educated Remote Interface Units in various ESA missions. For the Sentinel-2 and EarthCARE it was constructed also to include Solar Array Drive Electronics. The same control design as for Solar Array Drive function was also piggybacked in Magneto Torque control drives and other mission specific stepper motor drives. The purpose of this paper is to summarise and present the PATRIA Solar Array Drive Electronics design advantages.

  14. Hard x-ray imaging facility for space shuttle: A scientificq and conceptual engineering study

    Peterson, L.E.; Hudson, H.S.; Hurford, G.; Schneible, D.


    A shuttle-accommodated instrument for imaging hard X-rays in the study of nonthermal particles and high temperature particles in various solar and cosmic phenomena was defined and its feasibility demonstrated. The imaging system configuration is described as well as the electronics, aspect systems, mechanical and thermal properties and the ground support equipment.

  15. Diagnostics of underwater electrical wire explosion through a time- and space-resolved hard x-ray source

    Sheftman, D.; Shafer, D.; Efimov, S.; Gruzinsky, K.; Gleizer, S.; Krasik, Ya. E. [Physics Department, Technion, Haifa 32000 (Israel)


    A time- and space-resolved hard x-ray source was developed as a diagnostic tool for imaging underwater exploding wires. A {approx}4 ns width pulse of hard x-rays with energies of up to 100 keV was obtained from the discharge in a vacuum diode consisting of point-shaped tungsten electrodes. To improve contrast and image quality, an external pulsed magnetic field produced by Helmholtz coils was used. High resolution x-ray images of an underwater exploding wire were obtained using a sensitive x-ray CCD detector, and were compared to optical fast framing images. Future developments and application of this diagnostic technique are discussed.

  16. High-Efficiency Rad-Hard Ultra-Thin Si Photovoltaic Cell Technology for Space Project

    National Aeronautics and Space Administration — Improvements to solar cell efficiency that is consistent with low cost, high volume fabrication techniques are critical for future NASA space missions. In this...

  17. Rate dependent direct inverse hysteresis compensation of piezoelectric micro-actuator used in dual-stage hard disk drive head positioning system.

    Rahman, Md Arifur; Al Mamun, Abdullah; Yao, Kui


    The head positioning servo system in hard disk drive is implemented nowadays using a dual-stage actuator—the primary stage consisting of a voice coil motor actuator providing long range motion and the secondary stage controlling the position of the read/write head with fine resolution. Piezoelectric micro-actuator made of lead zirconate titanate (PZT) has been a popular choice for the secondary stage. However, PZT micro-actuator exhibits hysteresis—an inherent nonlinear characteristic of piezoelectric material. The advantage expected from using the secondary micro-actuator is somewhat lost by the hysteresis of the micro-actuator that contributes to tracking error. Hysteresis nonlinearity adversely affects the performance and, if not compensated, may cause inaccuracy and oscillation in the response. Compensation of hysteresis is therefore an important aspect for designing head-positioning servo system. This paper presents a new rate dependent model of hysteresis along with rigorous analysis and identification of the model. Parameters of the model are found using particle swarm optimization. Direct inverse of the proposed rate-dependent generalized Prandtl-Ishlinskii model is used as the hysteresis compensator. Effectiveness of the overall solution is underscored through experimental results.

  18. Rate dependent direct inverse hysteresis compensation of piezoelectric micro-actuator used in dual-stage hard disk drive head positioning system

    Rahman, Md. Arifur; Al Mamun, Abdullah; Yao, Kui


    The head positioning servo system in hard disk drive is implemented nowadays using a dual-stage actuator—the primary stage consisting of a voice coil motor actuator providing long range motion and the secondary stage controlling the position of the read/write head with fine resolution. Piezoelectric micro-actuator made of lead zirconate titanate (PZT) has been a popular choice for the secondary stage. However, PZT micro-actuator exhibits hysteresis—an inherent nonlinear characteristic of piezoelectric material. The advantage expected from using the secondary micro-actuator is somewhat lost by the hysteresis of the micro-actuator that contributes to tracking error. Hysteresis nonlinearity adversely affects the performance and, if not compensated, may cause inaccuracy and oscillation in the response. Compensation of hysteresis is therefore an important aspect for designing head-positioning servo system. This paper presents a new rate dependent model of hysteresis along with rigorous analysis and identification of the model. Parameters of the model are found using particle swarm optimization. Direct inverse of the proposed rate-dependent generalized Prandtl-Ishlinskii model is used as the hysteresis compensator. Effectiveness of the overall solution is underscored through experimental results.

  19. Why It Is Hard to Make Use of New Learning Spaces: A Script Perspective

    Kollar, Ingo; Pilz, Florian; Fischer, Frank


    The authors argue that a script perspective can lead to a better understanding of learning in new learning spaces. Scripts can be understood as flexible, individual memory structures guiding our understanding and actions, but also as instructional interventions that help students use the affordances offered in new learning spaces. In study 1 (N =…

  20. Extreme environment, rad hard, high performance, low power FPGA for space applications Project

    National Aeronautics and Space Administration — To enable NASA's next-generation missions, there is a critical need for a reconfigurable FPGA that can withstand the wide temperatures ranges and radiation of the...

  1. Sensorless State-Space Control of Elastic Two-Inertia Drive System Using a Minimum State Order Observer

    V. Comnac


    Full Text Available The paper presents sensorless state-space control of two-inertia drive system with resilient coupling. The control structure contains an I+PI controller for load speed regulation and a state feedback controller for effective vibration suppression of the elastic coupling. Mechanical state variable of two-inertia drive are obtained by using a linear minimum-order (Gopinath state observer. The design of the combined (I+PI and state feedback controller is achieved with the extended version of the modulus criterion [5]. The dynamic behavior of presented control structure has been examined, for different conditions, using MATLAB/SIMULINK simulation.

  2. A Near-Term Quantum Computing Approach for Hard Computational Problems in Space Exploration

    Smelyanskiy, Vadim N; Knysh, Sergey I; Williams, Colin P; Johnson, Mark W; Thom, Murray C; Macready, William G; Pudenz, Kristen L


    In this article, we show how to map a sampling of the hardest artificial intelligence problems in space exploration onto equivalent Ising models that then can be attacked using quantum annealing implemented in D-Wave machine. We overview the existing results as well as propose new Ising model implementations for quantum annealing. We review supervised and unsupervised learning algorithms for classification and clustering with applications to feature identification and anomaly detection. We introduce algorithms for data fusion and image matching for remote sensing applications. We overview planning problems for space exploration mission applications and algorithms for diagnostics and recovery with applications to deep space missions. We describe combinatorial optimization algorithms for task assignment in the context of autonomous unmanned exploration. Finally, we discuss the ways to circumvent the limitation of the Ising mapping using a "blackbox" approach based on ideas from probabilistic computing. In this ...

  3. Transient pulsar dynamics in hard x-rays: Prognoz 9 and GRIF "Mir" space experiments data

    Kudryavtsev, M I; Bogomolov, V V


    The long-term observations of the Galactic Centre as well as the Galactic anti-Centre regions in hard X-rays (10-300 keV) were made in experiments on board Prognoz-9 satellite and "Mir" orbital station (GRIF experiment). Some transient pulsars including A0535+262, GS1722-36, 4U1145-619, A1118-615, EXO2030+37, Sct X-1, SAX J2103.5+4545, IGR 16320-4751, IGR 16465-4507 were observed. The pulsation flux components of A0535+26 and GS1722-36 X-ray emission were revealed at significant level. For other observed pulsars the upper limits of pulsation intensity were obtained. The mean pulsation profiles of A0535+26 in different energy ranges as well as the energy spectra were obtained at different stages of outburst decreasing. The pulsation intensity-period behavior does not contradict the well-known correlation between spin-up rate and X-ray flux, while the stable character of the energy spectrum power index indicates on the absence of thermal component. The energy spectrum and mean pulsation profiles were also obtai...

  4. Twenty Years of Rad-Hard K14 SPAD in Space Projects

    Vojtěch Michálek


    Full Text Available During last two decades, several photon counting detectors have been developed in our laboratory. One of the most promising detector coming from our group silicon K14 Single Photon Avalanche Diode (SPAD is presented with its valuable features and space applications. Based on the control electronics, it can be operated in both gated and non-gated mode. Although it was designed for photon counting detection, it can be employed for multiphoton detection as well. With respect to control electronics employed, the timing jitter can be as low as 20 ps RMS. Detection efficiency is about 40%in range of 500 nm to 800 nm. The detector including gating and quenching circuitry has outstanding timing stability. Due to its radiation resistivity, the diode withstands 100 krad gamma ray dose without parameters degradation. Single photon detectors based on K14 SPAD were used for planetary altimeter and atmospheric lidar in MARS92/96 and Mars Surveyor ’98 space projects, respectively. Recent space applications of K14 SPAD comprises LIDAR and mainly time transfer between ground stations and artificial satellites. These include Laser Time Transfer, Time Transfer by Laser Link, and European Laser Timing projects.

  5. Small d-spacing WC/SiC multilayers for future hard X-ray telescope designs

    Jensen, C.P.; Madsen, K.K.; Christensen, Finn Erland


    interfacial roughness. With the new material combinations of WC/SiC the interface roughness can be reduced down to between 0.23 nm and 0.25 nm enabling bi-layer thicknesses down to 1.0 nm to reflect efficiently. The production of thinner period coatings thus enables the possibility for focusing optic designs......Multilayer coatings for reflecting hard X-rays up to 80keV, like W/Si and Pt/C, have been studied for several years. To go to higher energies, in the range of 100 keV to 250 keV, one needs coatings with smaller d-spacings than can currently be made with these material combinations, and a lower...

  6. A 1-D Study of the Ignition Space for Magnetic Indirect (X-ray) Drive Targets

    Cobble, James Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sinars, Daniel Brian [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    The ICF program today is investigating three approaches to achieving multi-MJ fusion yields and ignition: (1) laser indirect (x-ray) drive on the National Ignition Facility (NIF), (2) laser direct drive (primarily on the Omega laser facility at the University of Rochester), and (3) magnetic direct drive on the Z pulsed power facility. In this white paper we briefly consider a fourth approach, magnetic indirect drive, in which pulsedpower- driven x-ray sources are used in place of laser driven sources. We first look at some of the x-ray sources studied on Z prior to 2007 before the pulsed power ICF program shifted to magnetic direct drive. We then show results from a series of 1D Helios calculations of double-shell capsules that suggest that these sources, scaled to higher temperatures, could be a promising path to achieving multi-MJ fusion yields and ignition. We advocate here that more detailed design calculations with widely accepted 2D/3D ICF codes should be conducted for a better assessment of the prospects.

  7. Radiation-Hardened Solid-State Drive

    Sheldon, Douglas J.


    A method is provided for a radiationhardened (rad-hard) solid-state drive for space mission memory applications by combining rad-hard and commercial off-the-shelf (COTS) non-volatile memories (NVMs) into a hybrid architecture. The architecture is controlled by a rad-hard ASIC (application specific integrated circuit) or a FPGA (field programmable gate array). Specific error handling and data management protocols are developed for use in a rad-hard environment. The rad-hard memories are smaller in overall memory density, but are used to control and manage radiation-induced errors in the main, and much larger density, non-rad-hard COTS memory devices. Small amounts of rad-hard memory are used as error buffers and temporary caches for radiation-induced errors in the large COTS memories. The rad-hard ASIC/FPGA implements a variety of error-handling protocols to manage these radiation-induced errors. The large COTS memory is triplicated for protection, and CRC-based counters are calculated for sub-areas in each COTS NVM array. These counters are stored in the rad-hard non-volatile memory. Through monitoring, rewriting, regeneration, triplication, and long-term storage, radiation-induced errors in the large NV memory are managed. The rad-hard ASIC/FPGA also interfaces with the external computer buses.

  8. Globalisation and the foreignisation of space: The seven processes driving the current global land grab.

    Zoomers, E.B.


    The current global land grab is causing radical changes in the use and ownership of land. The main process driving the land grab, or ‘foreignisation of space’, as highlighted in the media and the emerging literature is the production of food and biofuel for export in the aftermath of recent food and


    Oleschuk V.I.


    Full Text Available Split-phase symmetrical motor drive on the base of two voltage source inverters, controlled by algorithms of synchronized pulse width modulation (PWM, has been investigated. Simulation results are presented for dual three-phase power conversion systems with continuous, discontinuous and combined versions of synchronized PWM.

  10. Optimization of the Robotic Joint Equipped with Epicyloidal Gear and Direct Drive for Space Applications

    Seweryn, Karol; Grassmann, Kamil; Ciesielska, Monika; Rybus, Tomasz; Turek, Michal


    One of the most critical element in the orbital manipulators are kinematic joints. Joints must be adapted to work in tough conditions of space environment and must ensure the greatest efficiency and work without backlash. At the Space Mechatronics and Robotics Laboratory (LMRS) of the Space Research Centre, PAS our team designed and built a lightweight kinematic pair based on a new concept. The new concept is based on the epicycloid two-stage gearbox with torque motor. In this paper we have focused on optimization of the joint design for space application. The optimization was focused on the minimization of the mass and backlash effects and on maximizing the joint efficiency.

  11. Protein folding: complex potential for the driving force in a two-dimensional space of collective variables.

    Chekmarev, Sergei F


    Using the Helmholtz decomposition of the vector field of folding fluxes in a two-dimensional space of collective variables, a potential of the driving force for protein folding is introduced. The potential has two components. One component is responsible for the source and sink of the folding flows, which represent respectively, the unfolded states and the native state of the protein, and the other, which accounts for the flow vorticity inherently generated at the periphery of the flow field, is responsible for the canalization of the flow between the source and sink. The theoretical consideration is illustrated by calculations for a model β-hairpin protein.

  12. Hard electronics; Hard electronics



    Hard material technologies were surveyed to establish the hard electronic technology which offers superior characteristics under hard operational or environmental conditions as compared with conventional Si devices. The following technologies were separately surveyed: (1) The device and integration technologies of wide gap hard semiconductors such as SiC, diamond and nitride, (2) The technology of hard semiconductor devices for vacuum micro- electronics technology, and (3) The technology of hard new material devices for oxides. The formation technology of oxide thin films made remarkable progress after discovery of oxide superconductor materials, resulting in development of an atomic layer growth method and mist deposition method. This leading research is expected to solve such issues difficult to be easily realized by current Si technology as high-power, high-frequency and low-loss devices in power electronics, high temperature-proof and radiation-proof devices in ultimate electronics, and high-speed and dense- integrated devices in information electronics. 432 refs., 136 figs., 15 tabs.

  13. Unilateral spring space regainer: A smart way to drive molar distally

    Abhishek Singha Roy


    Full Text Available Early loss of permanent teeth due to pathological or any other iatrogenic causes precludes development of normal intra-arch as well as interarch relationship. In recent years, non-extraction treatment approaches using non-compliance mechanics have become more popular in the successful resolution of space discrepancies. The following article describes an innovative spring, which is particularly suitable for unilateral space gaining with minimum side-effects. The utility of the spring has been illustrated in a case of bimaxillary protrusion.

  14. Time travel and warp drives a scientific guide to shortcuts through time and space

    Everett, Allen


    Sci-fi makes it look so easy. Receive a distress call from Alpha Centauri? No problem: punch the warp drive and you're there in minutes. Facing a catastrophe that can't be averted? Just pop back in the timestream and stop it before it starts. But for those of us not lucky enough to live in a science-fictional universe, are these ideas merely flights of fancy—or could it really be possible to travel through time or take shortcuts between stars?Cutting-edge physics may not be able to answer those questions yet, but it does offer up some tantalizing possibilities. In Time Travel and W

  15. On the influence of space storms on the frequency of infarct-myocardial, brain strokes, and hard car accidents; possible using of CR for their forecasting

    Dorman, L. I.; Iucci, N.; Ptitsyna, N. G.; Villoresi, G.

    We consider the influence of space storms as strong interplanetary shock waves causing great cosmic ray Forbush-decreases and big geomagnetic storms on the people health at the ground level We used data of more than 7 millions ambulance cases in Moscow and St Petersburg included information on daily numbers of the hard traffic accidents infarctions and brain strokes We found that during space storms the average daily numbers of hard traffic accidents with using ambulances as well as infarctions and brain strokes confirmed by medical personal increase by 17 4 pm 3 1 10 5 pm 1 2 and 7 0 pm 1 7 respectively We show that the forecasting of these dangerous apace phenomena can be done partly by using cosmic ray data on pre-increase and pre-decrease effects as well as on the change of 3-D cosmic ray anisotropy

  16. Hard electronics; Hard electronics



    In the fields of power conversion devices and broadcasting/communication amplifiers, high power, high frequency and low losses are desirable. Further, for electronic elements in aerospace/aeronautical/geothermal surveys, etc., heat resistance to 500degC is required. Devices which respond to such hard specifications are called hard electronic devices. However, with Si which is at the core of the present electronics, the specifications cannot fully be fulfilled because of the restrictions arising from physical values. Accordingly, taking up new device materials/structures necessary to construct hard electronics, technologies to develop these to a level of IC were examined and studied. They are a technology to make devices/IC of new semiconductors such as SiC, diamond, etc. which can handle higher temperature, higher power and higher frequency than Si and also is possible of reducing losses, a technology to make devices of hard semiconducter materials such as a vacuum microelectronics technology using ultra-micro/high-luminance electronic emitter using negative electron affinity which diamond, etc. have, a technology to make devices of oxides which have various electric properties, etc. 321 refs., 194 figs., 8 tabs.

  17. A novel space ocular syndrome is driving technology advances on and off the planet

    Donoviel, Dorit B.; Zimmer, Cheryl N.; Clayton, Richard


    Astronauts are experiencing ophthalmological changes including optic disc edema, globe flattening, choroidal folds, and significant hyperopic shifts. In a handful of cases in which it was measured, intracranial pressure as measured by lumbar punctures was elevated post-flight. The severity of symptoms is highly variable and the underlying etiology is unknown, but a spaceflight associated cephalad-fluid shift is thought to play a role. NASA requires portable, non-invasive, clinically-validated approaches to assessing the ocular and the cerebral physiological, anatomical, and functional changes. Multispectral Imaging (MSI) that enables instruments installed on satellites in space to observe Earth was applied in an ophthalmic medical device that is clinically being used on Earth and now being evaluated for use on humans in space. The Annidis RHA™ (Ottawa, Canada) uses narrow band light emitting diodes (LEDs) to create discrete slices of anatomical structures of the posterior pole of the eye. The LEDs cover a frequency range from 520 to 940 nm, which allow for specific visualization of the different features of the posterior segment of the eye including retina, choroid and optic nerve head. Interestingly, infrared illumination at 940 nm reflects from the posterior sclera, retro-illuminating the choroidal vasculature without the need for invasive contrast agents. Abnormalities in retinal, choroidal or cerebral venous drainage and/or arterial flow may contribute to the microgravity ocular syndrome (MOS) in astronauts; hence this space technology may prove to be invaluable for diagnosing not only the health of our planet but also of the humans living on it and above it.

  18. Analysis of the development and performance of hard disks

    Novak, Davorin


    With the emergence of new technologies in the field of hard drives we can witness a significant increase of surface density and transfer rate of interfaces which, as a result, enables greater performance and reliability of hard disks. The reason for this are increasing needs for higher capacities and data transfer rate to or from the hard disk. This thesis presents the structure of hard drives, features, performance and reliability of hard drives and alternative data storage technologies. Par...

  19. Generation of Domestic Hot Water, Space Heating and Driving Pattern Profiles for Integration Analysis of Active Loads in Low Voltage Grids

    Diaz de Cerio Mendaza, Iker; Pigazo, Alberto; Bak-Jensen, Birgitte


    demand and electric vehicle driving profiles, to be used for power grid calculations. The generated thermal profiles relied on a statistical analysis made from real domestic hot water and space heating data from 25 households of a typical Danish residential area. The driving profiles instead were formed......The changes in the Danish energy sector, consequence of political agreements, are expected to have direct impact in the actual power distribution systems. Large number of electric boiler, heat pumps and electric vehicles are planned and will cope large percentage of the future power consumption...... at household level. Despite of the well-known flexible service that this kind of loads can provide, their flexibility is highly dependent of the domestic hot water and space heating demand and the driving habits of each user. This paper presents two methodologies employed to randomly generate thermal power...

  20. A High Performance Space Vector Modulation - Direct Torque Controlled Induction Machine Drive based on Stator Flux Orientation Technique



    Full Text Available This paper proposes the design and implementation of a novel direct torque controlled induction machine drive system. The control system enjoys the advantages of stator vector control and conventional direct torque control and avoids some of the implementation difficulties of either of the two control methods. The stator vector control principal is used to keep constant the amplitude of stator flux vector at rated value, and to develop the relationship between the machine torque and the rotating speed of the stator flux vector. Thus, the machine torque can be regulated to generate the stator angular speed, which becomes a command signal and permits to overcome the problem of its estimation. Furthermore, with the combined control methods, the reference stator voltage vector can be generated and proportional-integral controllers and space vector modulation technique can be used to obtain fixed switching frequency and low torque ripple. Simulation experiments results indicate that, with the proposed scheme, a precise control of the stator flux and machine torque can be achieved. Compared to conventional direct torque control, presented method is easily implemented, and the steady performances of ripples of both torque and flux are considerably improved.

  1. Space and time harmonics related problems and their mitigation for position and speed sensorless slip-ring induction motor drives applications

    Subhasis Nandi


    There have been renewed interests in slip-ring induction machines due to their increasing use in both grid connected and stand-alone wind power generation schemes. Despite the squirrel cage induction generators’ advantages of being brushless, low-cost, needing less maintenance and having inherent overload protection, the biggest advantage of variable-speed wound rotor induction machines is in its doubled energy capture. Also in high power induction motor drives such as static Kramer drives or static Scherbius drives use of wound rotor induction motors is a must. Thus it becomes necessary to measure the speed of the machine for closed loop control for such high performance drives. Recently, a sensorless position and speed estimation scheme was proposed for wound rotor wind power generator. In this paper, the limitation of the scheme caused by space and time harmonics have been investigated. Simulation results have been presented to explain the mechanism of the space and time harmonics caused distortion of current. Experimental results showing the deterioration of speed detection scheme at light load for a slip-ring induction motor have been presented. Finally, improvements have been applied experimentally to obtain better speed estimation.

  2. Electricity generation in space from light-reflecting blades to drive a generator. Stromerzeugung im Weltall mittels lichtreflektierender Fluegel als Antriebskraft fuer Generatoren

    Hill, S.


    The invention refers to electricity generation in space by means of light reflecting blades to drive a generator. A piece of equipment which starts to rotate in space will continue to rotate indefinitely because of weightlessness. Only the friction forces require energy to overcome them. This requires a minimum amount of energy, which is easily provided by the idea of the invention, using light reflecting blades and the energy radiated by the sun. The invention is characterised by the fact that light-reflecting blades, as known from physics, are fixed to the rotor shaft to drive the generator. This type of electricity generation from light-reflecting blades can also be used on earth, but is more difficult here because of gravity. All the energy problems of satellites are solved by electricity generation in space by means of light-reflecting blades to drive generators, according to the invention. Further, the generated energy can be transmitted to the earth by radio, and can help to cover the energy needs of the earth.

  3. An accelerated life test model for harmonic drives under a segmental stress history and its parameter optimization

    Zhang Chao


    Full Text Available Harmonic drives have various distinctive advantages and are widely used in space drive mechanisms. Accelerated life test (ALT is commonly conducted to shorten test time and reduce associated costs. An appropriate ALT model is needed to predict the lifetime of harmonic drives with ALT data. However, harmonic drives which are used in space usually work under a segmental stress history, and traditional ALT models can hardly be used in this situation. This paper proposes a dedicated ALT model for harmonic drives applied in space systems. A comprehensive ALT model is established and genetic algorithm (GA is adopted to obtain optimal parameters in the model using the Manson fatigue damage rule to describe the fatigue failure process and a cumulative damage method to calculate and accumulate the damage caused by each segment in the stress history. An ALT of harmonic drives was carried out and experimental results show that this model is acceptable and effective.

  4. An accelerated life test model for harmonic drives under a segmental stress history and its parameter optimization

    Zhang Chao; Wang Shaoping; Wang Zimeng; Wang Xingjian


    Harmonic drives have various distinctive advantages and are widely used in space drive mechanisms. Accelerated life test (ALT) is commonly conducted to shorten test time and reduce associated costs. An appropriate ALT model is needed to predict the lifetime of harmonic drives with ALT data. However, harmonic drives which are used in space usually work under a segmental stress history, and traditional ALT models can hardly be used in this situation. This paper proposes a dedicated ALT model for harmonic drives applied in space systems. A comprehensive ALT model is established and genetic algorithm (GA) is adopted to obtain optimal parameters in the model using the Manson fatigue damage rule to describe the fatigue failure process and a cumulative dam-age method to calculate and accumulate the damage caused by each segment in the stress history. An ALT of harmonic drives was carried out and experimental results show that this model is acceptable and effective.

  5. dSPACE real time implementation of fuzzy PID position controller for vertical rotating single link arm robot using four-quadrant BLDC drive

    Manikandan Ramasamy


    Full Text Available Automation has been growing in recent years for the manufacturing industries to increase productivity. Multiple robotic arms are used to handle materials for lifting in flexible directions. The vertical rotation of a 360 degree single arm is considered in this research on a position servo drive with brushless DC motor. The load torque of an arm varies depending upon the angular displacement due to gravity, so it requires four-quadrant operation of the drive with a robust feedback controller. This paper deals with the design and performance comparison of a conventional PID feedback controller with a fuzzy-based PID controller and suggests the most suitable controller. The design was implemented in real time through the dSPACE DS1104 controller environment to verify the dynamic behaviors of the arm.

  6. Drive Stands

    Federal Laboratory Consortium — The Electrical Systems Laboratory (ESL)houses numerous electrically driven drive stands. A drive stand consists of an electric motor driving a gearbox and a mounting...

  7. Improving the Drive System of Permanent Magnet Linear Synchronous Motor Based on Direct Thrust Force Control Applying Space Vector Modulation

    Mehdi Manoochehri


    Full Text Available Applying the direct thrust force control (DFC method in permanent magnet linear synchronous motor (PMLSM leads to some important problems. The most important disadvantages of applying this method are electromagnetic force and linkage flux big ripple and variable switching frequency. In this paper space vector modulation (SVM technique is applied for removing the disadvantages of classic DFC method. SVM technique makes the switching frequency constant and provides continues Voltage space compared with discrete space in classic method. Simulation results confirmed the theory. They show that combining the DFC method with SVM technique removes lots of the disadvantages of classic DFC method like big ripples and variable switching and remains the benefits of this method.

  8. Importance of Joint Spacing and Rock Hardness on the Pattern and Efficiency of Glacial Erosion in Alpine Settings: an Example From Yosemite National Park, California.

    Duhnforth, M.; Anderson, R. S.; Ward, D. J.; Stock, G. M.


    Two topics of interest in alpine glacial valleys can be explored by sampling glacial polish for cosmogenic 10Be dating. First, deglaciation histories can be reconstructed if the sample surfaces are fully reset by glacial erosion during the last glacial cycle. Second, samples that are not completely reset can be used to document the pattern and rates of glacial erosion. We systematically sampled glacially-polished bedrock surfaces in the Tuolumne River watershed in Yosemite National Park, a landscape renowned for its glacially polished granites and granodiorites, for cosmogenic 10Be exposure dating. The samples were collected along an 80 km transect from the Tuolumne River drainage divide at 4000 m down to an elevation of 730 m just below Hetch Hetchy reservoir. The lowest sample position corresponds to the glacier terminus in the Tuolumne valley during the last glacial maximum (LGM). Samples were taken from at least eight different granitic/granodioritic units, which show differences in their hardness and joint spacing. These included the massive, flawless Cathedral Peak granodiorite and El Capitan granite. When inverted for exposure age, 17 out of our total of 23 measured 10Be samples yield ages between 3 and 20 ka ignoring any correction for snow shielding. These ages young from 15 ka to 3 ka with distance upvalley from the LGM terminal position. These samples constrain the post-LGM deglaciation history of the valley when the snow shielding correction is included. This pattern of fully reset samples is, however, interrupted at six sample locations with anomalously high concentrations of 10Be that far exceed those expected from exposure since deglaciation between 20 and 15 ka. These samples with significant inheritance all come from the poorly jointed, massive Cathedral Peak granodiorite and El Capitan granite. We interpret our results as indicating that rock type plays an important role in glacial erosion, and that in particular joint spacing strongly controls

  9. Cross-talk between Rho and Rac GTPases drives deterministic exploration of cellular shape space and morphological heterogeneity.

    Sailem, Heba; Bousgouni, Vicky; Cooper, Sam; Bakal, Chris


    One goal of cell biology is to understand how cells adopt different shapes in response to varying environmental and cellular conditions. Achieving a comprehensive understanding of the relationship between cell shape and environment requires a systems-level understanding of the signalling networks that respond to external cues and regulate the cytoskeleton. Classical biochemical and genetic approaches have identified thousands of individual components that contribute to cell shape, but it remains difficult to predict how cell shape is generated by the activity of these components using bottom-up approaches because of the complex nature of their interactions in space and time. Here, we describe the regulation of cellular shape by signalling systems using a top-down approach. We first exploit the shape diversity generated by systematic RNAi screening and comprehensively define the shape space a migratory cell explores. We suggest a simple Boolean model involving the activation of Rac and Rho GTPases in two compartments to explain the basis for all cell shapes in the dataset. Critically, we also generate a probabilistic graphical model to show how cells explore this space in a deterministic, rather than a stochastic, fashion. We validate the predictions made by our model using live-cell imaging. Our work explains how cross-talk between Rho and Rac can generate different cell shapes, and thus morphological heterogeneity, in genetically identical populations.

  10. Standard hardness conversion tables for metals relationship among brinell hardness, vickers hardness, rockwell hardness, superficial hardness, knoop hardness, and scleroscope hardness

    American Society for Testing and Materials. Philadelphia


    1.1 Conversion Table 1 presents data in the Rockwell C hardness range on the relationship among Brinell hardness, Vickers hardness, Rockwell hardness, Rockwell superficial hardness, Knoop hardness, and Scleroscope hardness of non-austenitic steels including carbon, alloy, and tool steels in the as-forged, annealed, normalized, and quenched and tempered conditions provided that they are homogeneous. 1.2 Conversion Table 2 presents data in the Rockwell B hardness range on the relationship among Brinell hardness, Vickers hardness, Rockwell hardness, Rockwell superficial hardness, Knoop hardness, and Scleroscope hardness of non-austenitic steels including carbon, alloy, and tool steels in the as-forged, annealed, normalized, and quenched and tempered conditions provided that they are homogeneous. 1.3 Conversion Table 3 presents data on the relationship among Brinell hardness, Vickers hardness, Rockwell hardness, Rockwell superficial hardness, and Knoop hardness of nickel and high-nickel alloys (nickel content o...

  11. Comparative study of SVPWM (space vector pulse width modulation) & SPWM (sinusoidal pulse width modulation) based three phase voltage source inverters for variable speed drive

    Ahmed, Waheed; Usman Ali, Syed M.


    We have performed comparative studies of Space Vector Pulse Width Modulation (SVPWM) and Sinusoidal Pulse Width Modulation (SPWM) techniques utilizing MATLAB tools. During these investigations, we carried out intensive simulations, comprehensively analyzed the obtained results and compared the harmonic density, power factor (PF), & switching losses of SVPWM and SPWM. It has been observed during investigations that if the switching frequency is high then losses due to harmonics are negligible, thus based on obtained results we suggested that the SVPWM technique is a more reliable solution. Because SVPWM utilizes DC bus voltage more efficiently, generates less Total Harmonic Distortion (THD) and has higher output quality it provides flexible control of output voltage and output frequency for Variable Speed Drive (VSD).

  12. Drugged Driving

    ... Parents & Educators Children & Teens Search Connect with NIDA : Google Plus Facebook LinkedIn Twitter YouTube Flickr RSS Menu ... misuse of prescription drugs can make driving a car unsafe—just like driving after drinking alcohol. Drugged ...

  13. Electric drives

    Boldea, Ion


    ENERGY CONVERSION IN ELECTRIC DRIVESElectric Drives: A DefinitionApplication Range of Electric DrivesEnergy Savings Pay Off RapidlyGlobal Energy Savings Through PEC DrivesMotor/Mechanical Load MatchMotion/Time Profile MatchLoad Dynamics and StabilityMultiquadrant OperationPerformance IndexesProblemsELECTRIC MOTORS FOR DRIVESElectric Drives: A Typical ConfigurationElectric Motors for DrivesDC Brush MotorsConventional AC MotorsPower Electronic Converter Dependent MotorsEnergy Conversion in Electric Motors/GeneratorsPOWER ELECTRONIC CONVERTERS (PECs) FOR DRIVESPower Electronic Switches (PESs)The

  14. Low-Power, Rad-hard Reconfigurable, Bi-directional Flexfet? Level Shifter ReBiLS for Multiple Generation Technology Integration for Space Exploration Project

    National Aeronautics and Space Administration — The many different generations of integrated circuit (IC) technologies required for new space exploration systems demand designs operate at multiple and often...

  15. 基于dSPACE的高速列车牵引传动系统%Drive system based on dSPACE platform for high-speed train

    葛兴来; 宋文胜; 冯晓云


    The variable-frequency speed regulation based on rotor flux control for the traction inverter-motor system with three-level diode NPC (Neutral-Point-Clamped) topology is analyzed covering whole speed range of high-speed train. The functional block of rotor-flux-oriented indirect vector control is given and its implementation algorithm is discussed in detail. The compensation algorithm for the precise modeling of the main circuit of three-level traction drive is presented,which considers the effect of dead-time and PWM sampling error. Its simulation model is built based on the hardware-in-the-loop real-time simulation platform of dSPACE and the traction drive control algorithm is programmed based on TMS320F2812 DSP. The comparison of control performance among different main circuit realization methods and among different calculation steps demonstrates the validity of the real-time simulation modeling algorithm and the drive control algorithm.%针对高速列车二极管中点箝位三电平拓扑牵引逆变器-牵引电机系统运行控制的要求,对牵引电机运行全速度范围中基于转子磁通控制的变频调速控制方式进行了分析,给出了转子磁场定向间接矢量控制功能框图并对实现算法进行了详细阐述.考虑死区效应和PWM采样误差的影响提出了三电平牵引传动主电路精确建模的补偿算法,建立了基于dSPACE半实物仿真平台的牵引传动主电路实时仿真模型,根据上述理论分析编制了基于TMS320F2812型DSP的牵引传动控制实现算法.对该控制算法在不同的主电路模型实现算法和不同计算步长下的实时仿真实验结果进行了对比分析,结果验证了该牵引传动主电路实时仿真建模算法和传动控制算法的有效性.

  16. Pile Driving


    Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

  17. Distracted Driving

    ... What's this? Submit What's this? Submit Button Distracted Driving Recommend on Facebook Tweet Share Compartir Each day in the United States, over 8 people are killed and 1,161 injured in crashes ...



    China is promoting environmentally friendly cars to save energy and protect the environment While people enjoy the pleasure and convenience of driving, they are also creating and breathing more and more toxic

  19. Hardness measures and resolution lower bounds

    Beyersdorff, Olaf; Kullmann, Oliver


    Various "hardness" measures have been studied for resolution, providing theoretical insight into the proof complexity of resolution and its fragments, as well as explanations for the hardness of instances in SAT solving. In this report we aim at a unified view of a number of hardness measures, including different measures of width, space and size of resolution proofs. We also extend these measures to all clause-sets (possibly satisfiable).

  20. Unified characterisations of resolution hardness measures

    Beyersdorff, O; Kullmann, O.


    Various "hardness" measures have been studied for resolution, providing theoretical insight into the proof complexity of resolution and its fragments, as well as explanations for the hardness of instances in SAT solving. In this paper we aim at a unified view of a number of hardness measures, including different measures of width, space and size of resolution proofs. Our main contribution is a unified game-theoretic characterisation of these measures. As consequences we obtain new relations b...

  1. Lunar Core Drive Tubes Summary

    National Aeronautics and Space Administration — Contains a brief summary and high resolution imagery from various lunar rock and core drive tubes collected from the Apollo and Luna missions to the moon.

  2. X-Ray Ccds for Space Applications: Calibration, Radiation Hardness, and Use for Measuring the Spectrum of the Cosmic X-Ray Background

    Gendreau, Keith Charles


    This thesis has two distinct components. One concerns the physics of the high energy resolution X-ray charge coupled devices (CCD) detectors used to measure the cosmic X-ray background (XRB) spectrum. The other involves the measurements and analysis of the XRB spectrum and instrumental background with these detectors on board the advanced satellite for cosmology and astrophysics (ASCA). The XRB has a soft component and a hard component divided at ~2 keV. The hard component is extremely isotropic, suggesting a cosmological origin. The soft component is extremely anisotropic. A galactic component most likely dominates the soft band with X-ray line emission due to a hot plasma surrounding the solar system. ASCA is one of the first of a class of missions designed to overlap the hard and soft X-ray bands. The X-ray CCD's energy resolution allows us to spectrally separate the galactic and cosmological components. Also, the resolution offers the ability to test several specific cosmological models which would make up the XRB. I have concentrated on models for the XRB origin which include active galactic nuclei (AGN) as principal components. I use ASCA data to put spectral constraints on the AGN synthesis model for the XRB. The instrumental portion of this thesis concerns the development and calibration of the X-ray CCDs. I designed, built and operated an X-ray calibration facility for these detectors. It makes use of a reflection grating spectrometer to measure absolute detection efficiency, characteristic absorption edge strengths, and spectral redistribution in the CCD response function. Part of my thesis research includes a study of radiation damage mechanisms in CCDs. This work revealed radiation damage-induced degradation in the spectral response to X-rays. It also uncovered systematic effects which affect both data analysis and CCD design. I have developed a model involving trap energy levels in the CCD band gap structure. These traps reduce the efficiency in which

  3. Pulsation driving and convection

    Antoci, Victoria


    Convection in stellar envelopes affects not only the stellar structure, but has a strong impact on different astrophysical processes, such as dynamo-generated magnetic fields, stellar activity and transport of angular momentum. Solar and stellar observations from ground and space have shown that the turbulent convective motion can also drive global oscillations in many type of stars, allowing to study stellar interiors at different evolutionary stages. In this talk I will concentrate on the influence of convection on the driving of stochastic and coherent pulsations across the Hertzsprung-Russell diagram and give an overview of recent studies.

  4. Exploring Forensic Implications of the Fusion Drive

    Shruti Gupta


    Full Text Available This paper explores the forensic implications of Apple's Fusion Drive. The Fusion Drive is an example of auto-tiered storage. It uses a combination of a flash drive and a magnetic drive. Data is moved between the drives automatically to maximize system performance. This is different from traditional caches because data is moved and not simply copied. The research included understanding the drive structure, populating the drive, and then accessing data in a controlled setting to observe data migration strategies. It was observed that all the data is first written to the flash drive with 4 GB of free space always maintained. If data on the magnetic drive is frequently accessed, it is promoted to the flash drive while demoting other information. Data is moved at a block-level and not a file-level. The Fusion Drive didn't alter the timestamps of files with data migration.

  5. Radiation Hard High Performance Optoelectronic Devices Project

    National Aeronautics and Space Administration — High-performance, radiation-hard, widely-tunable integrated laser/modulator chip and large-area avalanche photodetectors (APDs) are key components of optical...

  6. Death Drive

    Stühler, Rebekka Hellstrøm


    The aim of this project is to investigate why the Freudian term Death Drive is not acknowledged in modern psychological therapy. On basis of psychoanalytical theory and through a literary analysis, the project will present a discussion of the significance and presence of the term within these practises.

  7. Fusion of Built in Test (BIT) Technologies with Embeddable Fault Tolerant Techniques for Power System and Drives in Space Exploration Project

    National Aeronautics and Space Administration — As NASA develops next generation space exploration systems as part of the Constellation program, new prognostics and health management tools are needed to ensure...

  8. Thermodynamic hardness and the maximum hardness principle

    Franco-Pérez, Marco; Gázquez, José L.; Ayers, Paul W.; Vela, Alberto


    An alternative definition of hardness (called the thermodynamic hardness) within the grand canonical ensemble formalism is proposed in terms of the partial derivative of the electronic chemical potential with respect to the thermodynamic chemical potential of the reservoir, keeping the temperature and the external potential constant. This temperature dependent definition may be interpreted as a measure of the propensity of a system to go through a charge transfer process when it interacts with other species, and thus it keeps the philosophy of the original definition. When the derivative is expressed in terms of the three-state ensemble model, in the regime of low temperatures and up to temperatures of chemical interest, one finds that for zero fractional charge, the thermodynamic hardness is proportional to T-1(I -A ) , where I is the first ionization potential, A is the electron affinity, and T is the temperature. However, the thermodynamic hardness is nearly zero when the fractional charge is different from zero. Thus, through the present definition, one avoids the presence of the Dirac delta function. We show that the chemical hardness defined in this way provides meaningful and discernible information about the hardness properties of a chemical species exhibiting integer or a fractional average number of electrons, and this analysis allowed us to establish a link between the maximum possible value of the hardness here defined, with the minimum softness principle, showing that both principles are related to minimum fractional charge and maximum stability conditions.

  9. Steady accretion of an elastic body on a hard spherical surface and the notion of a four-dimensional reference space

    Tomassetti, Giuseppe; Cohen, Tal; Abeyaratne, Rohan


    Taking the cue from experiments on actin growth on spherical beads, we formulate and solve a model problem describing the accretion of an incompressible elastic solid on a rigid sphere due to attachment of diffusing free particles. One of the peculiar characteristics of this problem is that accretion takes place on the interior surface that separates the body from its support rather than on its exterior surface, and hence is responsible for stress accumulation. Simultaneously, ablation takes place at the outer surface where material is removed from the body. As the body grows, mechanical effects associated with the build-up of stress and strain energy slow down accretion and promote ablation. Eventually, the system reaches a point where internal accretion is balanced by external ablation. The present study is concerned with this stationary regime called "treadmilling". The principal ingredients of our model are: a nonstandard choice of the reference configuration, which allows us to cope with the continually evolving material structure; and a driving force and a kinetic law for accretion/ablation that involves the difference in chemical potential, strain energy and the radial stress. By combining these ingredients we arrive at an algebraic system which governs the stationary treadmilling state. We establish the conditions under which this system has a solution and we show that this solution is unique. Moreover, by an asymptotic analysis we show that for small beads the thickness of the solid is proportional to the radius of the support and is strongly affected by the stiffness of the solid, whereas for large beads the stiffness of the solid is essentially irrelevant, the thickness being proportional to a characteristic length that depends on the parameters that govern diffusion and accretion kinetics.

  10. Wear of hard materials by hard particles

    Hawk, Jeffrey A.


    Hard materials, such as WC-Co, boron carbide, titanium diboride and composite carbide made up of Mo2C and WC, have been tested in abrasion and erosion conditions. These hard materials showed negligible wear in abrasion against SiC particles and erosion using Al2O3 particles. The WC-Co materials have the highest wear rate of these hard materials and a very different material removal mechanism. Wear mechanisms for these materials were different for each material with the overall wear rate controlled by binder composition and content and material grain size.

  11. Radiation Hardness Assurance (RHA) Guideline

    Campola, Michael J.


    Radiation Hardness Assurance (RHA) consists of all activities undertaken to ensure that the electronics and materials of a space system perform to their design specifications after exposure to the mission space environment. The subset of interests for NEPP and the REAG, are EEE parts. It is important to register that all of these undertakings are in a feedback loop and require constant iteration and updating throughout the mission life. More detail can be found in the reference materials on applicable test data for usage on parts.

  12. Fusion of Built in Test (BIT) Technologies with Embeddable Fault Tolerant Techniques for Power System and Drives in Space Exploration Project

    National Aeronautics and Space Administration — Impact Technologies has proposed development of an effective prognostic and fault accommodation system for critical DC power systems including PV systems. Overall...

  13. Fine pitch CdTe-based Hard-X-ray polarimeter performance for space science in the 70-300 keV energy range

    Antier, S; Ferrando, P


    X-rays astrophysical sources have been almost exclusively characterized through imaging, spectroscopy and timing analysis. Nevertheless, more observational parameters are needed because some radiation mechanisms present in neutrons stars or black holes are still unclear. Polarization measurements will play a key role in discrimination between different X-ray emission models. Such a capability becomes a mandatory requirement for the next generation of high-energy space proposals. We have developed a CdTe-based fine-pitch imaging spectrometer, Caliste, able to respond to these new requirements. With a 580-micron pitch and 1 keV energy resolution at 60 keV, we are able to accurately reconstruct the polarization angle and polarization fraction of an impinging flux of photons which are scattered by 90{\\deg} after Compton diffusion within the crystal. Thanks to its high performance in both imaging and spectrometry, Caliste turns out to be a powerful device for high-energy polarimetry. In this paper, we present the ...

  14. Spaces

    Maziar Nekovee


    Full Text Available Cognitive radio is being intensively researched as the enabling technology for license-exempt access to the so-called TV White Spaces (TVWS, large portions of spectrum in the UHF/VHF bands which become available on a geographical basis after digital switchover. Both in the US, and more recently, in the UK the regulators have given conditional endorsement to this new mode of access. This paper reviews the state-of-the-art in technology, regulation, and standardisation of cognitive access to TVWS. It examines the spectrum opportunity and commercial use cases associated with this form of secondary access.

  15. Raman Spectroscopy Characterization of amorphous carbon coatings for computer hard disks

    Ager III, Joel W.


    Amorphous carbon films are used as protective coatings on magnetic media to protect the magnetic layer from wear and abrasion caused by the read/write head during hard disk drive start-up and operation. A key requirement in increasing the storage capacity and reliability of hard-disk drives is improving the performance of these coatings. This cooperative agreement used optical characterization techniques developed at LBNL to study thin-film hard disk media produced by Seagate Technology...

  16. Simulations of driven overdamped frictionless hard spheres

    Lerner, Edan; Düring, Gustavo; Wyart, Matthieu


    We introduce an event-driven simulation scheme for overdamped dynamics of frictionless hard spheres subjected to external forces, neglecting hydrodynamic interactions. Our event-driven approach is based on an exact equation of motion which relates the driving force to the resulting velocities through the geometric information characterizing the underlying network of contacts between the hard spheres. Our method allows for a robust extraction of the instantaneous coordination of the particles as well as contact force statistics and dynamics, under any chosen driving force, in addition to shear flow and compression. It can also be used for generating high-precision jammed packings under shear, compression, or both. We present a number of additional applications of our method.

  17. Stephen Hawking "drives a hard bargain with life"



    @@ 英国著名的物理学家Stephen Hawking被誉为"the world's most famous living physicist".在美国的Time杂志举办的评选"Time 100:the most influential persons of the century"活动中,据称在评选"scientists and thinkers"方面的代表人物时,由于在每个大的科学领域只能选一个人物,因此在理论物理领域选出了当之无愧的物理学家Albert Einstein,而后者在活动的最后还被选为"the person of the century".但是,在介绍爱因斯坦的专辑中,杂志特别邀请了Stephen Hawking撰写介绍Einstein的成就和贡献的文章.几乎为世所公认的是,Hawking取得的成就堪与Einstein媲美.尽管他未能入选该杂志的20世纪100名人录,但这并没有削弱他的卓著声誉和巨大贡献.

  18. Hardness Tester for Polyur

    Hauser, D. L.; Buras, D. F.; Corbin, J. M.


    Rubber-hardness tester modified for use on rigid polyurethane foam. Provides objective basis for evaluation of improvements in foam manufacturing and inspection. Typical acceptance criterion requires minimum hardness reading of 80 on modified tester. With adequate correlation tests, modified tester used to measure indirectly tensile and compressive strengths of foam.

  19. Comprehensive hard materials


    Comprehensive Hard Materials deals with the production, uses and properties of the carbides, nitrides and borides of these metals and those of titanium, as well as tools of ceramics, the superhard boron nitrides and diamond and related compounds. Articles include the technologies of powder production (including their precursor materials), milling, granulation, cold and hot compaction, sintering, hot isostatic pressing, hot-pressing, injection moulding, as well as on the coating technologies for refractory metals, hard metals and hard materials. The characterization, testing, quality assurance and applications are also covered. Comprehensive Hard Materials provides meaningful insights on materials at the leading edge of technology. It aids continued research and development of these materials and as such it is a critical information resource to academics and industry professionals facing the technological challenges of the future. Hard materials operate at the leading edge of technology, and continued res...

  20. The space-time transition characteristics and its driving mechanism of county-scale inbound tourism in Zhejiang province%浙江省县域入境旅游时空跃迁特征及驱动机制

    张子昂; 黄震方; 曹芳东; 王坤; 陈晓艳


    characteristics and types of inbound tourism are measured in each county by means of LISA time path and the space-time transition.In this way,nesting the quantile regression model and space-time evolution type is achieved,which also promotes the construction of space-time transition driving mechanism model.The result shows that the county-scale inbound tourism in Zhejiang has the obvious feature of spatial aggregation-with Hangzhou playing a dominant role.Moreover,the spatial self-organizing feature is increasingly reinforced while its spatial differences are gradually lessened,the latter of which can be reflected at the local level.On the one hand,the revolution pattem of county-scale inbound tourism in this province is feature by significantly positive space integration;on the other hand,there is a degree of transfer inertia between counties.Apart from that,it is shown that the inbound tourism of the backward counties located in the northwest and southeast parts has a relatively dynamic local spatial feature.To be more specific,Changshan county has the most significant volatility in the spatial dependence while the Daishan county has the best stability.In addition,the space-time transition driving patterns of county-scale inbound tourism in Zhejiang are divided into four categories (driving the industry-structure driving pattem,the economy-service restriction modes,the trade-industry driving pattem and the location-resource restriction modes),which present an obvious evolution process which starts from synthetic development and then gradually turns into synthetic restriction from northeast to southwest area.There are less driving areas and more restricted areas at low quantile level,while more driving areas and less restricted areas at high quantile level.And the four main patterns imply different influence mechanisms.

  1. Dynamic hardness of metals

    Liang, Xuecheng

    Dynamic hardness (Pd) of 22 different pure metals and alloys having a wide range of elastic modulus, static hardness, and crystal structure were measured in a gas pulse system. The indentation contact diameter with an indenting sphere and the radius (r2) of curvature of the indentation were determined by the curve fitting of the indentation profile data. r 2 measured by the profilometer was compared with that calculated from Hertz equation in both dynamic and static conditions. The results indicated that the curvature change due to elastic recovery after unloading is approximately proportional to the parameters predicted by Hertz equation. However, r 2 is less than the radius of indenting sphere in many cases which is contradictory to Hertz analysis. This discrepancy is believed due to the difference between Hertzian and actual stress distributions underneath the indentation. Factors which influence indentation elastic recovery were also discussed. It was found that Tabor dynamic hardness formula always gives a lower value than that directly from dynamic hardness definition DeltaE/V because of errors mainly from Tabor's rebound equation and the assumption that dynamic hardness at the beginning of rebound process (Pr) is equal to kinetic energy change of an impact sphere over the formed crater volume (Pd) in the derivation process for Tabor's dynamic hardness formula. Experimental results also suggested that dynamic to static hardness ratio of a material is primarily determined by its crystal structure and static hardness. The effects of strain rate and temperature rise on this ratio were discussed. A vacuum rotating arm apparatus was built to measure Pd at 70, 127, and 381 mum sphere sizes, these results exhibited that Pd is highly depended on the sphere size due to the strain rate effects. P d was also used to substitute for static hardness to correlate with abrasion and erosion resistance of metals and alloys. The particle size effects observed in erosion were

  2. Inside Solid State Drives (SSDs)

    Micheloni, Rino; Eshghi, Kam


    Solid State Drives (SSDs) are gaining momentum in enterprise and client applications, replacing Hard Disk Drives (HDDs) by offering higher performance and lower power. In the enterprise, developers of data center server and storage systems have seen CPU performance growing exponentially for the past two decades, while HDD performance has improved linearly for the same period. Additionally, multi-core CPU designs and virtualization have increased randomness of storage I/Os. These trends have shifted performance bottlenecks to enterprise storage systems. Business critical applications such as online transaction processing, financial data processing and database mining are increasingly limited by storage performance. In client applications, small mobile platforms are leaving little room for batteries while demanding long life out of them. Therefore, reducing both idle and active power consumption has become critical. Additionally, client storage systems are in need of significant performance improvement as well ...

  3. The PTZ kindling mouse model of epilepsy exhibits exploratory drive deficits and aberrant activity amongst VTA dopamine neurons in both familiar and novel space.

    Ahmadi, Mahboubeh; Dufour, Jean-Philippe; Seifritz, Erich; Mirnajafi-Zadeh, Javad; Saab, Bechara J


    Recurrent seizures that define epilepsy are often accompanied by psychosocial problems and cognitive deficits with incompletely understood aetiology. We therefore used the pentylenetetrazol (PTZ) kindling model of epilepsy in mice to examine potential seizure-associated neuropathologies, focusing on motivation, memory and novel-environment-induced activation of midbrain dopaminergic neurons. In addition to recurrent seizures, we found that PTZ kindling led to a strong suppression of novelty-driven exploration while largely sparing fear-driven exploration. The deficits in exploratory drive may be relevant for other cognitive impairments since reduced unassisted rearing in a learning arena correlated with poorer spatial memory of object location. Using c-Fos immunofluorescence as a marker of neuronal activity, we observed that dopamine neurons within the ventral tegmental area (VTA) of PTZ kindled mice demonstrate hyperactivity at baseline and hypoactivity in response to a novel environment compared to saline-injected cagemate controls. These data extend previous findings of PTZ kindling-mediated disruptions of hippocampal processes important for novel environment recognition and learning by demonstrating PTZ kindling also induces motivational deficits that are associated with reduced stimulus-evoked activation of VTA dopamine neurons. More broadly, these data help understand the aetiology of complex behavioural changes in the PTZ kindling model, and may assist in the development of superior diagnoses and treatments for epilepsy. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Hardness and excitation energy

    Á Nagy


    The concept of the ensemble Kohn-Sham hardness is introduced. It is shown that the first excitation energy can be given by the Kohn-Sham hardness (i.e. the energy difference of the ground-state lowest unoccupied and highest occupied levels) plus an extra term coming from the partial derivative of the ensemble exchange-correlation energy with respect to the weighting factor in the limit → 0. It is proposed that the first excitation energy can be used as a reactivity index instead of the hardness.

  5. Hard probes 2006 Asilomar


    "The second international conference on hard and electromagnetic probes of high-energy nuclear collisions was held June 9 to 16, 2006 at the Asilomar Conference grounds in Pacific Grove, California" (photo and 1/2 page)

  6. Warp Drive - From Imagination to Reality

    Gardiner, J.

    The realisation of warp drive is far beyond current science and technology; nevertheless, setting out a timetable for the realisation of warp drive is instructive as this will set expectations for the progress of future research. It is proposed that a time scale for the realisation of warp drive can be estimated by historical analogy with the development of manned space travel to the Moon, using conventional project estimation techniques. A timeline for space travel to the Moon begins with Cyrano de Bergerac's Voyage dans la Lune in 1657 and culminates with the Apollo 11 Moon landing in 1969, a little over 300 years later. A similar timeline for warp drive begins with John W. Campbell's novel Islands of Space in 1930. Fictional conjecture on the warp drive has given way to serious scientific speculation following publication of Alcubierre's seminal warp drive paper in 1994. It is concluded that the realisation of warp drive might be achieved around the year 2180. A projected timetable for the realisation of warp drive through phases of conjecture , speculation , science , technology and application suggests that the warp drive proposal should enter the science phase around the year 2030.

  7. Hard and Soft

    Claes H. de Vreese; Boomgaarden, Hajo G.; Semetko, Holli A.


    Abstract Support for European integration is a function no longer only of `hard' economic and utilitarian predictors but also of `soft' predictors such as feelings of identity and attitudes towards immigrants. Focusing on the issue of the potential membership of Turkey in the European Union (EU), this study demonstrates that the importance of `soft' predictors outweighs the role of `hard' predictors in understanding public opinion about Turkish membership. The study draws on survey...

  8. Hardness amplification in nondeterministic logspace

    Gupta, Sushmita


    A hard problem is one which cannot be easily computed by efficient algorithms. Hardness amplification is a procedure which takes as input a problem of mild hardness and returns a problem of higher hardness. This is closely related to the task of decoding certain error-correcting codes. We show amplification from mild average case hardness to higher average case hardness for nondeterministic logspace and worst-to-average amplification for nondeterministic linspace. Finally we explore possible ...

  9. Ion drive - A step toward 'Star Trek'

    Atkins, K. L.; Terwilliger, C.


    The design of a solar-powered electric propulsion system is seen as the first step in the ultimate development of an ion drive system which might incorporate many features of a spacecraft propulsion system described in a science fiction novel written by Anderson (1970). The considered ion propulsion systems would make it possible to augment significantly the operational capabilities of space transportation systems utilizing the Shuttle orbiter in combination with a solid-propellant interim upper stage. The use of the ion drive in a number of applications is discussed, giving attention to the resulting enhancement of national space capabilities, the role of the ion drive in the space transportation system, the development and the operation of a manned space station, satellite positioning and service, the elimination of space debris objects, the study of Halley's comet, interplanetary or lunar shuttle services, and space missions involving the outer planets.

  10. High Torque, Direct Drive Electric Motor Project

    National Aeronautics and Space Administration — Bear Engineering proposes to advance the development of an innovative high torque, low speed, direct drive motor in order to meet NASA's requirements for such...

  11. High Torque, Direct Drive Electric Motor Project

    National Aeronautics and Space Administration — Bear Engineering proposes to develop an innovative high torque, low speed, direct drive motor in order to meet NASA's requirements for such devices. Fundamentally,...

  12. Developing Castable Metal Harmonic Drives Project

    National Aeronautics and Space Administration — This effort utilizes the high elastic strain limit and net-shaped processing of metallic glasses to fabricate low-cost harmonic drives that outperform steel. ...

  13. High-Performance, Radiation-Hard, 2-D, Near-Infrared, Avalanche Photodiode Arrays Project

    National Aeronautics and Space Administration — In this STTR project we will address the radiation hardness issues using radiation hard (RH) materials. We will based on the RH material to develop our photon...

  14. Multi-propeller drive system

    Belenger, Robert V.


    A multipropeller drive system having a single input shaft for connection to an engine system, a differential gear assembly for dividing the driving force from the input drive shaft between a pair of output shafts, and a pair of laterally spaced propellers driven by the output shafts of the differential gear assembly is disclosed. The differential gear assembly operates in a manner wherein one output shaft, if required, is permitted to revolve at a different rate than the other output shaft. A pair of brake mechanisms acting on the output shafts of the differential gear assembly enable an operator to control the rotational speed of the respective propellers without modifying the engine speed or transmission settings.

  15. CLIC Drive Beam Position Monitor

    Smith, S; Gudkov, D; Soby, L; Syratchev, I


    CLIC, an electron-positron linear collider proposed to probe the TeV energy scale, is based on a two-beam scheme where RF power to accelerate a high energy luminosity beam is extracted from a high current drive beam. The drive beam is efficiently generated in a long train at modest frequency and current then compressed in length and multiplied in frequency via bunch interleaving. The drive beam decelerator requires >40000 quadrupoles, each holding a beam position monitor (BPM). Though resolution requirements are modest (2 microns) these BPMs face several challenges. They must be compact and inexpensive. They must operate below waveguide cutoff to insure locality of position signals, ruling out processing at the natural 12 GHz bunch spacing frequency. Wakefields must be kept low. We find compact conventional stripline BPM with signals processed below 40 MHz can meet requirements. Choices of mechanical design, operating frequency, bandwidth, calibration and processing algorithm are presented. Calculations of wa...

  16. Hard and superhard nanocomposite coatings

    Musil, J. [Univ. of West Bohemia, Plzen (Czech Republic). Dept. of Phys.


    This article reviews the development of hard coatings from a titanium nitride film through superlattice coatings to nanocomposite coatings. Significant attention is devoted to hard and superhard single layer nanocomposite coatings. A strong correlation between the hardness and structure of nanocomposite coatings is discussed in detail. Trends in development of hard nanocomposite coatings are also outlined. (orig.)


    Piotr FOLĘGA


    Full Text Available The variety of types and sizes currently in production harmonic drive is a problem in their rational choice. Properly selected harmonic drive must meet certain requirements during operation, and achieve the anticipated service life. The paper discusses the problems associated with the selection of the harmonic drive. It also presents the algorithm correct choice of harmonic drive. The main objective of this study was to develop a computer program that allows the correct choice of harmonic drive by developed algorithm.

  18. Session: Hard Rock Penetration

    Tennyson, George P. Jr.; Dunn, James C.; Drumheller, Douglas S.; Glowka, David A.; Lysne, Peter


    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Hard Rock Penetration - Summary'' by George P. Tennyson, Jr.; ''Overview - Hard Rock Penetration'' by James C. Dunn; ''An Overview of Acoustic Telemetry'' by Douglas S. Drumheller; ''Lost Circulation Technology Development Status'' by David A. Glowka; ''Downhole Memory-Logging Tools'' by Peter Lysne.

  19. Hard-hat day


    CERN will be organizing a special information day on Friday, 27th June, designed to promote the wearing of hard hats and ensure that they are worn correctly. A new prevention campaign will also be launched.The event will take place in the hall of the Main Building from 11.30 a.m. to 2.00 p.m., when you will be able to come and try on various models of hard hat, including some of the very latest innovative designs, ask questions and pass on any comments and suggestions.

  20. Hardness of metallic crystals

    Wuhui Li; Fengzhang Ren; Juanhua Su; Zhanhong Ma; Ke Cao; Baohong Tian


    This paper presents a new formula for calculating the hardness of metallic crystals, resulted from the research on the critical grain size with stable dislocations. The formula is = 6 /[(1 – )], where is the hardness, the coefficient, the shear modulus, the Poisson’s ratio, a function of the radius of an atom () and the electron density at the atom interface (). The formula will not only be used to testify the critical grain size with stable dislocations, but also play an important role in the understanding of mechanical properties of nanocrystalline metals.

  1. Hard exclusive QCD processes

    Kugler, W.


    Hard exclusive processes in high energy electron proton scattering offer the opportunity to get access to a new generation of parton distributions, the so-called generalized parton distributions (GPDs). This functions provide more detailed informations about the structure of the nucleon than the usual PDFs obtained from DIS. In this work we present a detailed analysis of exclusive processes, especially of hard exclusive meson production. We investigated the influence of exclusive produced mesons on the semi-inclusive production of mesons at fixed target experiments like HERMES. Further we give a detailed analysis of higher order corrections (NLO) for the exclusive production of mesons in a very broad range of kinematics. (orig.)

  2. Adaptive Lobster-Eye Hard X-Ray Telescope Project

    National Aeronautics and Space Administration — To address NASA needs for hard X-ray telescopes for starlight detection and wavefront analysis, Physical Optics Corporation (POC) proposes to develop an Adjustable...

  3. Self-lubricating Hard Coatings for Extreme Environment Project

    National Aeronautics and Space Administration — This program will develop low friction hard coatings for lubricating mechanical and tribological components used for exploring Mars, the Moon, asteroids, comets and...

  4. Scotch-Tape Mirror for Hard X-rays Project

    National Aeronautics and Space Administration — The project is to build a grazing incidence mirror for hard X-rays (E>20 keV) using a “scotch-tape” design, in which a thin plastic tape with a...

  5. Scotch-Tape Mirror for Hard X-rays Project

    National Aeronautics and Space Administration — The project is to build a grazing incidence mirror for hard X-rays (E>20 keV) using a “scotch-tape” design, in which a thin plastic tape with a...

  6. Extreme Temperature, Rad-Hard Power Management ASIC Project

    National Aeronautics and Space Administration — Ridgetop Group will design a rad-hard Application Specific Integrated Circuit (ASIC) for spacecraft power management that is functional over a temperature range of...

  7. High Operating Temperature, Radiation-Hard MIM Thermophotovoltaic Converters Project

    National Aeronautics and Space Administration — Spire Corporation proposes to investigate InGaAs thermophotovoltaic (TPV) cells optimized for high temperature operation (~150C) and radiation hardness against the...

  8. Hard Probes at ATLAS

    Citron, Z; The ATLAS collaboration


    The ATLAS collaboration has measured several hard probe observables in Pb+Pb and p+Pb collisions at the LHC. These measurements include jets which show modification in the hot dense medium of heavy ion collisions as well as color neutral electro-weak bosons. Together, they elucidate the nature of heavy ion collisions.

  9. Rock-hard coatings

    Muller, M.


    Aircraft jet engines have to be able to withstand infernal conditions. Extreme heat and bitter cold tax coatings to the limit. Materials expert Dr Ir. Wim Sloof fits atoms together to develop rock-hard coatings. The latest invention in this field is known as ceramic matrix composites. Sloof has sign

  10. Budgeting in Hard Times.

    Parrino, Frank M.


    Interviews with school board members and administrators produced a list of suggestions for balancing a budget in hard times. Among these are changing calendars and schedules to reduce heating and cooling costs; sharing personnel; rescheduling some extracurricular activities; and forming cooperative agreements with other districts. (MLF)

  11. Hard and Soft Governance

    Moos, Lejf


    The governance and leadership at transnational, national and school level seem to be converging into a number of isomorphic forms as we see a tendency towards substituting 'hard' forms of governance, that are legally binding, with 'soft' forms based on persuasion and advice. This article analyses...

  12. Running in Hard Times

    Berry, John N., III


    Roberta Stevens and Kent Oliver are campaigning hard for the presidency of the American Library Association (ALA). Stevens is outreach projects and partnerships officer at the Library of Congress. Oliver is executive director of the Stark County District Library in Canton, Ohio. They have debated, discussed, and posted web sites, Facebook pages,…

  13. Hard times; Schwere Zeiten

    Grunwald, Markus


    The prices of silicon and solar wafers keep dropping. According to market research specialist IMS research, this is the result of weak traditional solar markets and global overcapacities. While many manufacturers are facing hard times, big producers of silicon are continuing to expand.

  14. Driving After a Stroke

    ... Inspirational Stories Stroke Heroes Among Us Driving After Stroke Updated:Jul 23,2015 Can I drive after ... more tips for daily living . Let's Talk About Stroke Fact Sheets Our stroke fact sheets cover treatments, ...

  15. Electric Vehicle - Economical driving

    Jensen, VCE, Steen V.; Schøn, Henriette


    Instruct the reader in getting most satisfaction out of an EV, especially concerning driving and loading.......Instruct the reader in getting most satisfaction out of an EV, especially concerning driving and loading....

  16. Dementia and driving

    ... this page: // Dementia and driving To use the sharing features on ... please enable JavaScript. If your loved one has dementia , deciding when they can no longer drive may ...

  17. Analysis of Vehicle Steering and Driving Bifurcation Characteristics

    Xianbin Wang


    Full Text Available The typical method of vehicle steering bifurcation analysis is based on the nonlinear autonomous vehicle model deriving from the classic two degrees of freedom (2DOF linear vehicle model. This method usually neglects the driving effect on steering bifurcation characteristics. However, in the steering and driving combined conditions, the tyre under different driving conditions can provide different lateral force. The steering bifurcation mechanism without the driving effect is not able to fully reveal the vehicle steering and driving bifurcation characteristics. Aiming at the aforementioned problem, this paper analyzed the vehicle steering and driving bifurcation characteristics with the consideration of driving effect. Based on the 5DOF vehicle system dynamics model with the consideration of driving effect, the 7DOF autonomous system model was established. The vehicle steering and driving bifurcation dynamic characteristics were analyzed with different driving mode and driving torque. Taking the front-wheel-drive system as an example, the dynamic evolution process of steering and driving bifurcation was analyzed by phase space, system state variables, power spectral density, and Lyapunov index. The numerical recognition results of chaos were also provided. The research results show that the driving mode and driving torque have the obvious effect on steering and driving bifurcation characteristics.

  18. Gear bearing drive

    Weinberg, Brian (Inventor); Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor)


    A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

  19. Theory of hard photoproduction

    Klasen, Michael


    The present theoretical knowledge about photons and hard photoproduction processes, i.e. the production of jets, light and heavy hadrons, quarkonia, and prompt photons in photon-photon and photon-hadron collisions, is reviewed. Virtual and polarized photons and prompt photon production in hadron collisions are also discussed. The most important leading and next-to-leading order QCD results are compiled in analytic form. A large variety of numerical predictions is compared to data from TRISTAN...


    Mansur, Louis K [ORNL; Bhattacharya, R [UES, Incorporated, Dayton, OH; Blau, Peter Julian [ORNL; Clemons, Art [ORNL; Eberle, Cliff [ORNL; Evans, H B [UES, Incorporated, Dayton, OH; Janke, Christopher James [ORNL; Jolly, Brian C [ORNL; Lee, E H [Consultant, Milpitas, CA; Leonard, Keith J [ORNL; Trejo, Rosa M [ORNL; Rivard, John D [ORNL


    High energy ion beam surface treatments were applied to a selected group of polymers. Of the six materials in the present study, four were thermoplastics (polycarbonate, polyethylene, polyethylene terephthalate, and polystyrene) and two were thermosets (epoxy and polyimide). The particular epoxy evaluated in this work is one of the resins used in formulating fiber reinforced composites for military helicopter blades. Measures of mechanical properties of the near surface regions were obtained by nanoindentation hardness and pin on disk wear. Attempts were also made to measure erosion resistance by particle impact. All materials were hardness tested. Pristine materials were very soft, having values in the range of approximately 0.1 to 0.5 GPa. Ion beam treatment increased hardness by up to 50 times compared to untreated materials. For reference, all materials were hardened to values higher than those typical of stainless steels. Wear tests were carried out on three of the materials, PET, PI and epoxy. On the ion beam treated epoxy no wear could be detected, whereas the untreated material showed significant wear.

  1. Radiation Hardness Assurance (RHA): Challenges and New Considerations

    Campola, Michael J.


    Use of commercial-off-the-shelf (COTS) components and emerging technologies often require space flight missions to accept elevated risk. The Radiation Hardness Assurance (RHA) flow includes environment definition, hazard evaluation, requirements definition, evaluation of design, and design trades to accommodate and mitigate the risk a project or program takes. Depending on the mission profile and environment, different missions may not necessarily benefit from the same risk reduction efforts or cost reduction attempts. While this poses challenges for the radiation engineer, it also presents opportunities to tailor the RHA flow to minimize risk based on the environment or design criticality while remaining within budget. This presentation will focus on an approach to RHA amidst the present challenges, using the same RHA flow as in the past, with examples from recent radiation test results. The current challenges and the types of risk will be identified. How these risks drive requirements development and realization will be explained with examples of device results and data for single event effects (SEE) and in one case total ionizing dose (TID).

  2. Simple Driving Techniques

    Rosendahl, Mads


    -like language. Our aim is to extract a simple notion of driving and show that even in this tamed form it has much of the power of more general notions of driving. Our driving technique may be used to simplify functional programs which use function composition and will often be able to remove intermediate data......Driving was introduced as a program transformation technique by Valentin Turchin in some papers around 1980. It was intended for the programming language REFAL and used in metasystem transitions based on super compilation. In this paper we present one version of driving for a more conventional lisp...

  3. High performance AC drives

    Ahmad, Mukhtar


    This book presents a comprehensive view of high performance ac drives. It may be considered as both a text book for graduate students and as an up-to-date monograph. It may also be used by R & D professionals involved in the improvement of performance of drives in the industries. The book will also be beneficial to the researchers pursuing work on multiphase drives as well as sensorless and direct torque control of electric drives since up-to date references in these topics are provided. It will also provide few examples of modeling, analysis and control of electric drives using MATLAB/SIMULIN

  4. Exhaust powered drive shaft torque enhancer

    Koch, A.B.


    This patent describes a power producing combination including an internal combustion engine and a mounting frame therefor, and power transmission means including rotating drive shaft means connected to the engine. The improvement described here is a drive shaft torque enhancing device, the device comprising: a multiplicity of blades secured to the drive shaft, equally spaced therearound, each generally lying in a plane containing the axis of the drive shaft; torque enhancer feed duct means for selectively directing a stream of exhaust gases from the engine to impact against the blades to impart torque to the drive shaft; and wherein the power producing combination is used in a vehicle, the vehicle having braking means including a brake pedal; and the power producing combination further comprising torque enhancer disengagement means responsive to motion of the brake pedal.

  5. Space space space

    Trembach, Vera


    Space is an introduction to the mysteries of the Universe. Included are Task Cards for independent learning, Journal Word Cards for creative writing, and Hands-On Activities for reinforcing skills in Math and Language Arts. Space is a perfect introduction to further research of the Solar System.

  6. Driving Competence in Mild Dementia with Lewy Bodies: In Search of Cognitive Predictors Using Driving Simulation

    Stephanie Yamin


    Full Text Available Driving is a multifactorial behaviour drawing on multiple cognitive, sensory, and physical systems. Dementia is a progressive and degenerative neurological condition that impacts the cognitive processes necessary for safe driving. While a number of studies have examined driving among individuals with Alzheimer’s disease, less is known about the impact of Dementia with Lewy Bodies (DLB on driving safety. The present study compared simulated driving performance of 15 older drivers with mild DLB with that of 21 neurologically healthy control drivers. DLB drivers showed poorer performance on all indicators of simulated driving including an increased number of collisions in the simulator and poorer composite indicators of overall driving performance. A measure of global cognitive function (i.e., the Mini Mental State Exam was found to be related to the overall driving performance. In addition, measures of attention (i.e., Useful Field of View, UFOV and space processing (Visual Object and Space Perception, VOSP, Test correlated significantly with a rater’s assessment of driving performance.

  7. Theory of hard photoproduction

    Klasen, M. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik


    The present theoretical knowledge about photons and hard photoproduction processes, i.e. the production of jets, light and heavy hadrons, quarkonia, and prompt photons in photon-photon and photon-hadron collisions, is reviewed. Virtual and polarized photons and prompt photon production in hadron collisions are also discussed. The most important leading and next-to-leading order QCD results are compiled in analytic form. A large variety of numerical predictions is compared to data from TRISTAN, LEP, and HERA and extended to future electron and muon colliders. The sources of all relevant results are collected in a rich bibliography. (orig.)

  8. The Impact of Hard Disk Firmware Steganography on Computer Forensics

    Iain Sutherland


    Full Text Available The hard disk drive is probably the predominant form of storage media and is a primary data source in a forensic investigation. The majority of available software tools and literature relating to the investigation of the structure and content contained within a hard disk drive concerns the extraction and analysis of evidence from the various file systems which can reside in the user accessible area of the disk. It is known that there are other areas of the hard disk drive which could be used to conceal information, such as the Host Protected Area and the Device Configuration Overlay. There are recommended methods for the detection and forensic analysis of these areas using appropriate tools and techniques. However, there are additional areas of a disk that have currently been overlooked.  The Service Area or Platter Resident Firmware Area is used to store code and control structures responsible for the functionality of the drive and for logging failing or failed sectors.This paper provides an introduction into initial research into the investigation and identification of issues relating to the analysis of the Platter Resident Firmware Area. In particular, the possibility that the Platter Resident Firmware Area could be manipulated and exploited to facilitate a form of steganography, enabling information to be concealed by a user and potentially from a digital forensic investigator.

  9. Lectures on magnetohydrodynamical drives

    Loigom, Villem

    The paper deals with nonconventional types of electrical machines and drives - magnetohydrodynamical (MHD) machines and drives. In cardinal it is based on the research conducted with participation of the author in Tallinn Technical University at the Institute of Electrical Drives and Power Electronics, where the use of magnetohydrodynamical motors and drives in the metallurgical and casting industries have been studied for a long time. Major research interests include the qualities and applications of the induction MHD-drives for set in the motion (pumping, turning, dosing, mixing, etc.) non-ferrous molten metals like Al, Mg, Sn, Pb, Na, K, and their alloys. The first part of the paper describes induction MHD motors and their electrohydraulical qualities. In the second part energy conversion problems are described. Also, on the basis of the analogy between electromechanical and electrohydraulical phenomenas, static and dynamic qualities of MHD drives with induction MHD machines are discussed.

  10. National Radiation Hardness Assurance (RHA) Planning For NASA Missions: Updated Guidance

    LaBel, Kenneth A.; Pellish, Jonathan Allen


    Radiation Hardness Assurance (RHA) is the process of ensuring space system performance in the presence of a space radiation environment. Herein, we present an updated NASA methodology for RHA focusing on content, deliverables and timeframes.

  11. Notional Radiation Hardness Assurance (RHA) Planning For NASA Missions: Updated Guidance

    LaBel, Kenneth A.; Pellish, Jonathan A.


    Radiation Hardness Assurance (RHA) is the process of ensuring space system performance in the presence of a space radiation environment. Herein, we present an updated NASA methodology for RHA focusing on content, deliverables and timeframes.

  12. Radiation hard Monolithic SDRAM to support DDR2 and DDR3 architectures Project

    National Aeronautics and Space Administration — There is no rad hard SDRAM currently available to support DDR2 and DDR3 applications. Space Micro proposes to build a radiation hardened by design (RHBD) SDRAM...

  13. Universal Drive Train Facility

    Federal Laboratory Consortium — This vehicle drive train research facility is capable of evaluating helicopter and ground vehicle power transmission technologies in a system level environment. The...

  14. Hardness variability in commercial and hardened technologies

    Shaneyfelt, M.R.; Winokur, P.S.; Meisenheimer, T.L.; Sexton, F.W.; Roeske, S.B.; Knoll, M.G.


    Over the past 10 years, there have been a number of advances in methods to assess and assure the radiation hardness of microelectronics in military and space applications. At the forefront of these is the Qualified Manufacturers List (QML) methodology, in which the hardness of product is ``built-in`` through statistical process control (SPC) of technology parameters relevant to the radiation response, test structure to integrated circuit (IC) correlations, and techniques for extrapolating laboratory test results to varying radiation scenarios. At the same time, there has been renewed interest in the use of commercial technology -- with its enhanced performance, reduced cost, and higher reliability -- in military and space systems. In this paper, we initially demonstrate the application of QML techniques to assure and control the radiation response of hardened technologies. Through several examples, we demonstrate intra-die, wafer-to-wafer, and lot-to-lot variations in a hardened technology. We observe 10 to 30% variations in key technology parameters that result from variability in geometry, process, and design layout. Radiation-induced degradation is seen to mirror preirradiation characteristics. We then evaluate commercial technologies and report considerably higher variability in radiation hardness, i.e., variations by a factor of two to five. This variability is shown to arise from a lack of control of technology parameters relevant to the radiation response, which a commercial manufacturer has no interest in controlling in a normal process flow.

  15. Hard and Soft Governance

    Moos, Lejf


    and discusses governance forms at several levels. The first layer is the global: the methods of 'soft governance' that are being utilised by transnational agencies. The second layer is the national and local: the shift in national and local governance seen in many countries, but here demonstrated in the case......The governance and leadership at transnational, national and school level seem to be converging into a number of isomorphic forms as we see a tendency towards substituting 'hard' forms of governance, that are legally binding, with 'soft' forms based on persuasion and advice. This article analyses...... of Denmark, and finally the third layer: the leadership used in Danish schools. The use of 'soft governance' is shifting the focus of governance and leadership from decisions towards influence and power and thus shifting the focus of the processes from the decision-making itself towards more focus...

  16. Hard photoproduction at HERA

    Klasen, M. [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier / CNRS-IN2P3, 53 Avenue des Martyrs, F-38026 Grenoble (France)


    In view of possible photoproduction studies in ultra-peripheral heavy-ion collisions at the LHC, we briefly review the present theoretical understanding of photons and hard photoproduction processes at HERA, discussing the production of jets, light and heavy hadrons, quarkonia, and prompt photons. We address in particular the extraction of the strong coupling constant from photon structure function and inclusive jet measurements, the infrared safety and computing time of jet definitions, the sensitivity of di-jet cross sections on the parton densities in the photon, factorization breaking in diffractive di-jet production, the treatment of the heavy-quark mass in charm production, the relevance of the color-octet mechanism for quarkonium production, and isolation criteria for prompt photons. (author)

  17. Hard jet probes in terms of colorless QCD dipoles

    Peschanski, R


    the forward jet playing the role of a hard probe is analyzed in terms of QCD dipole (color-singlet q\\bar q) configurations in the transverse position space. There are sizable differences with the analogous q\\bar q configurations of a hard photon which may lead to significant phenomenological consequences on the analysis of hard processes using a forward jet probe, e.g. at the Tevatron. A geometrical interpretation of the resulting distribution in terms of black disk diffraction is proposed.

  18. Vibro-Acoustic Model of a Disk Drive

    Lee, Ming-Ran; Singh, Rajendra

    A new mathematical model of the vibro-acoustic characteristics of a computer hard-disk drive is presented in this paper. In particular, a mobility transfer function is defined that links sound radiated by a stationary or rotating disk to electromagnetic torque pulsations and structural dynamics. A simplified disk-drive system consisting of a brushless d.c. motor driving a single disk-spindle assembly, which is mounted on a flexible casing, is considered as the example case. Parametric studies illustrate the roles of bearing stiffness and disk geometry on the vibration and radiated sound.

  19. Growth of Magnetic Disk Drive Industry and Future


    Hard disk drives became the major information storage devices, supported by rapidly advancing magnetic recording technology. In this paper, several technical challenges to overcome the superparamagnetic limit are explained. The longitudinal magnetic recording shall be extended more than 100 Gb/in2, by adopting new media structure to stabilize the magnetization decay.

  20. Piezoelectric drive circuit

    Treu, Jr., Charles A.


    A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes.

  1. Fundamentals of electrical drives

    Veltman, André; De Doncker, Rik W


    Provides a comprehensive introduction to various aspects of electrical drive systems. This volume provides a presentation of dynamic generic models that cover all major electrical machine types and modulation/control components of a drive as well as dynamic and steady state analysis of transformers and electrical machines.

  2. Electric vehicles: Driving range

    Kempton, Willett


    For uptake of electric vehicles to increase, consumers' driving-range needs must be fulfilled. Analysis of the driving patterns of personal vehicles in the US now shows that today's electric vehicles can meet all travel needs on almost 90% of days from a single overnight charge.

  3. Recognizing driving in haste

    Rendón-Vélez, E.


    One can often hear people discussing the reasons why a road accident has happened: “She had to pick up her kids in the school before four o’clock and she was driving in haste and careless”, “He was stressed, he wanted to reach the beginning of the football match, tried to drive faster and didn't app

  4. Drive Around the World

    Yang Wei


    @@ "It's so cool that I can drive on my own,and my own car,"Cao Gang,WOrking for a private company in Changsha,capital city of Hunan Province,mid-south China,said in excitement when he newly bought Ben Ben,a Chinese local auto brand of Chang'an,with his freshly-passed driving license.

  5. Recognizing driving in haste

    Rendón-Vélez, E.


    One can often hear people discussing the reasons why a road accident has happened: “She had to pick up her kids in the school before four o’clock and she was driving in haste and careless”, “He was stressed, he wanted to reach the beginning of the football match, tried to drive faster and didn't app

  6. Electric Vehicle - Economical driving

    Jensen, VCE, Steen V.; Schøn, Henriette


    How do you reduce the energy-wast when driving and loading EV's - or rather: How do I get more km/l out of an EV......How do you reduce the energy-wast when driving and loading EV's - or rather: How do I get more km/l out of an EV...

  7. Recognizing driving in haste

    Rendón-Vélez, E.


    One can often hear people discussing the reasons why a road accident has happened: “She had to pick up her kids in the school before four o’clock and she was driving in haste and careless”, “He was stressed, he wanted to reach the beginning of the football match, tried to drive faster and didn't

  8. Optimal Control Development System for Electrical Drives

    Marian GAICEANU


    Full Text Available In this paper the optimal electrical drive development system is presented. It consists of both electrical drive types: DC and AC. In order to implement the optimal control for AC drive system an Altivar 71 inverter, a Frato magnetic particle brake (as load, three-phase induction machine, and dSpace 1104 controller have been used. The on-line solution of the matrix Riccati differential equation (MRDE is computed by dSpace 1104 controller, based on the corresponding feedback signals, generating the optimal speed reference for the AC drive system. The optimal speed reference is tracked by Altivar 71 inverter, conducting to energy reduction in AC drive. The classical control (consisting of rotor field oriented control with PI controllers and the optimal one have been implemented by designing an adequate ControlDesk interface. The three-phase induction machine (IM is controlled at constant flux. Therefore, the linear dynamic mathematical model of the IM has been obtained. The optimal control law provides transient regimes with minimal energy consumption. The obtained solution by integration of the MRDE is orientated towards the numerical implementation-by using a zero order hold. The development system is very useful for researchers, doctoral students or experts training in electrical drive. The experimental results are shown.

  9. Lower Hybrid Current Drive Experiments on Alcator C-Mod: Comparison with Theory and Simulation

    Bonoli, Paul


    Recently, lower hybrid current drive (LHCD) experiments have been carried out on Alcator C-Mod using an RF system consisting of 12 klystrons at 4.6 GHz, feeding a 4 x 22 waveguide array. Up to 900 kW of LH power has been coupled in the range1.6 PLH 0.3 [1]. We have simulated the LH current drive in these discharges using the combined ray tracing / 3D (r, v, v//) Fokker Planck code GENRAY -- CQL3D [2] and found similar current drive efficiencies. Measurements of nonthermal x-ray emission and electron cyclotron emission (ECE) confirm the presence of a significant fast electron population that varies with waveguide phasing and plasma density. Studies are currently underway to investigate the role of fast electron diffusion and full-wave effects such as diffractional broadening in determining the spatial and velocity space structure of the nonthermal electrons. The 3D (r, v, v//) electron distribution function from CQL3D has been used in synthetic diagnostic codes to simulate the measured hard x-ray and ECE emissions. Fast electron diffusion times have been inferred from x-ray data by employing a radial diffusion operator in CQL3D and determining the fast electron diffusivities that are required to reproduce the experimentally observed profiles of hard x-ray emission. Finally, we have been performing full-wave LH field simulations using the massively parallel TORIC --LH solver [3] in order to assess spatial and spectral broadening of the incident wave front that can result from diffraction and wave focusing effects. [1] R. Parker, Bull. Am. Phys. Soc. 51, 20 (2006). [2] R.W. Harvey and M. McCoy, ``The CQL3D Fokker Planck Code,'' Proc. IAEA Tech. Comm. Meeting on Simulation and Modeling of Thermonuclear Plasmas, Montreal, Canada, 1992. [3] J. C. Wright et al., Nucl. Fusion 45, 1411 (2005).

  10. Fault-Tolerant, Radiation-Hard DSP

    Czajkowski, David


    Commercial digital signal processors (DSPs) for use in high-speed satellite computers are challenged by the damaging effects of space radiation, mainly single event upsets (SEUs) and single event functional interrupts (SEFIs). Innovations have been developed for mitigating the effects of SEUs and SEFIs, enabling the use of very-highspeed commercial DSPs with improved SEU tolerances. Time-triple modular redundancy (TTMR) is a method of applying traditional triple modular redundancy on a single processor, exploiting the VLIW (very long instruction word) class of parallel processors. TTMR improves SEU rates substantially. SEFIs are solved by a SEFI-hardened core circuit, external to the microprocessor. It monitors the health of the processor, and if a SEFI occurs, forces the processor to return to performance through a series of escalating events. TTMR and hardened-core solutions were developed for both DSPs and reconfigurable field-programmable gate arrays (FPGAs). This includes advancement of TTMR algorithms for DSPs and reconfigurable FPGAs, plus a rad-hard, hardened-core integrated circuit that services both the DSP and FPGA. Additionally, a combined DSP and FPGA board architecture was fully developed into a rad-hard engineering product. This technology enables use of commercial off-the-shelf (COTS) DSPs in computers for satellite and other space applications, allowing rapid deployment at a much lower cost. Traditional rad-hard space computers are very expensive and typically have long lead times. These computers are either based on traditional rad-hard processors, which have extremely low computational performance, or triple modular redundant (TMR) FPGA arrays, which suffer from power and complexity issues. Even more frustrating is that the TMR arrays of FPGAs require a fixed, external rad-hard voting element, thereby causing them to lose much of their reconfiguration capability and in some cases significant speed reduction. The benefits of COTS high

  11. Hard coal; Steinkohle

    Loo, Kai van de; Sitte, Andreas-Peter [Gesamtverband Steinkohle e.V. (GVSt), Herne (Germany)


    International the coal market in 2014 was the first time in a long time in a period of stagnation. In Germany, the coal consumption decreased even significantly, mainly due to the decrease in power generation. Here the national energy transition has now been noticable affected negative for coal use. The political guidances can expect a further significant downward movement for the future. In the present phase-out process of the German hard coal industry with still three active mines there was in 2014 no decommissioning. But the next is at the end of 2015, and the plans for the time after mining have been continued. [German] International war der Markt fuer Steinkohle 2014 erstmals seit langem wieder von einer Stagnation gekennzeichnet. In Deutschland ging der Steinkohlenverbrauch sogar deutlich zurueck, vor allem wegen des Rueckgangs in der Stromerzeugung. Hier hat sich die nationale Energiewende nun spuerbar und fuer die Steinkohlennutzung negativ ausgewirkt. Die politischen Weichenstellungen lassen fuer die Zukunft eine weitere erhebliche Abwaertsbewegung erwarten. Bei dem im Auslaufprozess befindlichen deutschen Steinkohlenbergbau mit noch drei aktiven Bergwerken gab es 2014 keine Stilllegung. Doch die naechste steht zum Jahresende 2015 an, und die Planungen fuer die Zeit nach dem Bergbau sind fortgefuehrt worden.

  12. Current European developments in solar paddle drives

    Bentall, R. H.


    The European Space Research and Technology Centre (ESTEC) is sponsoring the development of a number of critical spacecraft hardware items. The hardware under development includes two competing solar paddle drives which are being produced to similar specifications. Three mechanisms of each type are being produced and will undergo thermal vacuum testing. All mechanisms have lead lubricated bearings.

  13. Measuring the Hardness of Minerals

    Bushby, Jessica


    The author discusses Moh's hardness scale, a comparative scale for minerals, whereby the softest mineral (talc) is placed at 1 and the hardest mineral (diamond) is placed at 10, with all other minerals ordered in between, according to their hardness. Development history of the scale is outlined, as well as a description of how the scale is used…

  14. Why All the Hard Work?



    The stereotype of the hard working Chinese has been around for a long time in the West. As early a 1894, Arthur Smith, a missionary who spent 54 years in China, wrote book introducing the hard-working Chinese people to Americans. In his book Chinese Characteristics, Smith wrote about the dili

  15. Phase behavior of hard particles

    Duijneveldt, J.S. van; Lekkerkerker, H.N.W.


    The phase behavior of hard particles and mixtures thereof is reviewed. Special attention is given to a lattice model consisting of hard hexagons and points on a triangular lattice. This model appears to have two disordered phases and an ordered phase.

  16. Melting of polydisperse hard disks

    Pronk, S.; Frenkel, D.


    The melting of a polydisperse hard-disk system is investigated by Monte Carlo simulations in the semigrand canonical ensemble. This is done in the context of possible continuous melting by a dislocation-unbinding mechanism, as an extension of the two-dimensional hard-disk melting problem. We find

  17. Melting of polydisperse hard disks

    Pronk, S.; Frenkel, D.


    The melting of a polydisperse hard-disk system is investigated by Monte Carlo simulations in the semigrand canonical ensemble. This is done in the context of possible continuous melting by a dislocation-unbinding mechanism, as an extension of the two-dimensional hard-disk melting problem. We find th

  18. Turbulent current drive mechanisms

    McDevitt, Christopher J.; Tang, Xian-Zhu; Guo, Zehua


    Mechanisms through which plasma microturbulence can drive a mean electron plasma current are derived. The efficiency through which these turbulent contributions can drive deviations from neoclassical predictions of the electron current profile is computed by employing a linearized Coulomb collision operator. It is found that a non-diffusive contribution to the electron momentum flux as well as an anomalous electron-ion momentum exchange term provide the most efficient means through which turbulence can modify the mean electron current for the cases considered. Such turbulent contributions appear as an effective EMF within Ohm's law and hence provide an ideal means for driving deviations from neoclassical predictions.

  19. Polar Direct Drive

    Skupsky, S.


    Direct drive offers the potential of higher target gain on the National Ignition Facility (NIF) than x-ray drive: The initial direct-drive target design had a 1-D gain of 45 and consisted primarily of a pure cryogenic DT shell. Using the expected levels of target and laser nonuniformities for the NIF, two-dimensional (2-D) hydrodynamic simulations predicted target gains around 30.(P.W. McKenty et al.), Phys. Plasmas 8, 2315 (2001). More-recent designs have shown that higher target gains could be obtained by replacing a portion of the DT shell with ``wetted'' CH foam and by using adiabat shaping: (1) Higher-Z material (C) in the foam increases laser absorption by about 40% (from 60% absorption to 85%).(S. Skupsky et al.), in Inertial Fusion Sciences and Applications 2001, edited by K. Tanaka et al. (Elsevier, Paris, 2002), p. 240. (2) Adiabat shaping allows the main portion of the fuel to be placed on a lower adiabat without compromising target stability.(V.N. Goncharov et al.), Phys. Plasmas 10, 1906 (2003). These direct-drive concepts can be tested on the NIF, long before that facility is converted to a direct-drive (spherically symmetric) irradiation configuration. Using the NIF x-ray-drive beam configuration, some of the near-polar beams could be pointed to better illuminate the target's equator. These more-oblique, equatorial beams will have lower absorption and reduced drive efficiency than the polar beams. One strategy to compensate for the difference in polar and equatorial drive is to reduce the irradiation at the poles and employ different pulse shapes to accommodate the time-dependent variations in drive and absorption. This concept of polar direct drive (PDD) has been studied using the 2-D hydrocode DRACO to determine the requirements for achieving ignition and moderate target gain for the NIF. Experiments on the OMEGA laser will examine the effects of oblique irradiation on target drive. Results of simulations for different direct-drive target designs

  20. Estimating Hardness from the USDC Tool-Bit Temperature Rise

    Bar-Cohen, Yoseph; Sherrit, Stewart


    A method of real-time quantification of the hardness of a rock or similar material involves measurement of the temperature, as a function of time, of the tool bit of an ultrasonic/sonic drill corer (USDC) that is being used to drill into the material. The method is based on the idea that, other things being about equal, the rate of rise of temperature and the maximum temperature reached during drilling increase with the hardness of the drilled material. In this method, the temperature is measured by means of a thermocouple embedded in the USDC tool bit near the drilling tip. The hardness of the drilled material can then be determined through correlation of the temperature-rise-versus-time data with time-dependent temperature rises determined in finite-element simulations of, and/or experiments on, drilling at various known rates of advance or known power levels through materials of known hardness. The figure presents an example of empirical temperature-versus-time data for a particular 3.6-mm USDC bit, driven at an average power somewhat below 40 W, drilling through materials of various hardness levels. The temperature readings from within a USDC tool bit can also be used for purposes other than estimating the hardness of the drilled material. For example, they can be especially useful as feedback to control the driving power to prevent thermal damage to the drilled material, the drill bit, or both. In the case of drilling through ice, the temperature readings could be used as a guide to maintaining sufficient drive power to prevent jamming of the drill by preventing refreezing of melted ice in contact with the drill.

  1. Assessment: A Driving Force.

    Rakow, Steven J.


    Asserts that educational assessment drives the curriculum. Thus, assessment is very important in contemplating reform in science education. Assessment should be an integral part of the instructional process, utilizing diagnostic testing, monitoring, and summative evaluations. (PR)

  2. Driving in a womb


    Drive thousands of kilometres on just a litre of fuel? During the annual Shell eco-marathon at the end of May, schoolchildren and students – including a team from TU Delft – demonstrated that it can indeed be done.

  3. Mongoose: Creation of a Rad-Hard MIPS R3000

    Lincoln, Dan; Smith, Brian


    This paper describes the development of a 32 Bit, full MIPS R3000 code-compatible Rad-Hard CPU, code named Mongoose. Mongoose progressed from contract award, through the design cycle, to operational silicon in 12 months to meet a space mission for NASA. The goal was the creation of a fully static device capable of operation to the maximum Mil-883 derated speed, worst-case post-rad exposure with full operational integrity. This included consideration of features for functional enhancements relating to mission compatibility and removal of commercial practices not supported by Rad-Hard technology. 'Mongoose' developed from an evolution of LSI Logic's MIPS-I embedded processor, LR33000, code named Cobra, to its Rad-Hard 'equivalent', Mongoose. The term 'equivalent' is used to infer that the core of the processor is functionally identical, allowing the same use and optimizations of the MIPS-I Instruction Set software tool suite for compilation, software program trace, etc. This activity was started in September of 1991 under a contract from NASA-Goddard Space Flight Center (GSFC)-Flight Data Systems. The approach affected a teaming of NASA-GSFC for program development, LSI Logic for system and ASIC design coupled with the Rad-Hard process technology, and Harris (GASD) for Rad-Hard microprocessor design expertise. The program culminated with the generation of Rad-Hard Mongoose prototypes one year later.

  4. Instant Google Drive starter

    Procopio, Mike


    This book is a Starter which teaches you how to use Google Drive practically. This book is perfect for people of all skill levels who want to enjoy the benefits of using Google Drive to safely store their files online and in the cloud. It's also great for anyone looking to learn more about cloud computing in general. Readers are expected to have an Internet connection and basic knowledge of using the internet.

  5. Marine winch drive systems

    Clifford, M.; Smith, P.M.


    In the design of marine winch drive systems, efficiency, controllability, compactness and component layout flexibility are major considerations. This paper discusses design concepts aimed at achieving the above considerations in the design of variable speed, hydrostatic, marine winch drive systems. These concepts utilize a high pressure, load sensing pump, and a low-speed, high-torque (LSHT), radial-piston, hydraulic motor. These components are then shown applied in several open circuit hydrostatic power transmission systems.

  6. Dementia and driving.

    O'Neill, D; Neubauer, K; Boyle, M; Gerrard, J; Surmon, D; Wilcock, G K


    Many European countries test cars, but not their drivers, as they age. There is evidence to suggest that human factors are more important than vehicular factors as causes of motor crashes. The elderly also are involved in more accidents per distance travelled than middle-aged drivers. As the UK relies on self-certification of health by drivers over the age of 70 years, we examined the driving practices of patients with dementia attending a Memory Clinic. Nearly one-fifth of 329 patients with documented dementia continued to drive after the onset of dementia, and impaired driving ability was noted in two-thirds of these. Their families experienced great difficulty in persuading patients to stop driving, and had to invoke outside help in many cases. Neuropsychological tests did not help to identify those who drove badly while activity of daily living scores were related to driving ability. These findings suggest that many patients with dementia drive in an unsafe fashion after the onset of the illness. The present system of self-certification of health by the elderly for driver-licensing purposes needs to be reassessed.

  7. Self-driving carsickness.

    Diels, Cyriel; Bos, Jelte E


    This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and productivity. However, we here show that the envisaged scenarios all lead to an increased risk of motion sickness. As such, the benefits this technology is assumed to bring may not be capitalised on, in particular by those already susceptible to motion sickness. This can negatively affect user acceptance and uptake and, in turn, limit the potential socioeconomic benefits that this emerging technology may provide. Following a discussion on the causes of motion sickness in the context of self-driving cars, we present guidelines to steer the design and development of automated vehicle technologies. The aim is to limit or avoid the impact of motion sickness and ultimately promote the uptake of self-driving cars. Attention is also given to less well known consequences of motion sickness, in particular negative aftereffects such as postural instability, and detrimental effects on task performance and how this may impact the use and design of self-driving cars. We conclude that basic perceptual mechanisms need to be considered in the design process whereby self-driving cars cannot simply be thought of as living rooms, offices, or entertainment venues on wheels.

  8. Driving Force Filtering and Driving Mechanism Analysis of Urban Agricultural Development in Weifang County, China

    SUI Fei-fei


    Full Text Available As an agricultural nation, the agricultural landscape is the basic appearance and existence in China, but the common existence often be neglected and contempted. As a new type of design and ideology, the development of urban agricultural landscape will greatly affect the texture and structure of the urban space. According to the urban agricultural production data and the socio-economic data of Weifang County, a set of evaluation index system that could analyze quantitatively the driving force of urban agricultural production changes and the internal drive mechanism was built. The original driving force indicators of economy, society, resources and environment from the time-series were chosen, and then 15 driving forces from the original driving forces by correlation analysis and principal component analysis were selected. The degree of influence was analyzed and the driving forces model by means of partial least squares(PLS was built. The results demonstrated that the factors greatly influenced the increase of urban agricultural output value in Weifang County were per capita net income of rural residents, agricultural machinery total power, effective irrigation area, centralized treatment rate of urban sewage, with the driving exponents 0.2509, 0.1019, 0.1655, 0.1332, respectively. The negative influence factor was the use amount of agricultural plastic film and the driving exponent was-0.2146. The research provides a reference for the development of urban agriculture, as well as a reference for the related study.

  9. A comparison of the 60Co gamma radiation hardness, breakdown characteristics and the effect of SiNx capping on InAlN and AlGaN HEMTs for space applications

    Smith, M. D.; O'Mahony, D.; Vitobello, F.; Muschitiello, M.; Costantino, A.; Barnes, A. R.; Parbrook, P. J.


    Electrical performance and stability of InAlN and AlGaN high electron mobility transistors (HEMTs) subjected 9.1 mrad of 60Co gamma radiation and off-state voltage step-stressing until breakdown are reported. Comparison with commercially available production-level AlGaN HEMT devices, which showed negligible drift in DC performance throughout all experiments, suggests degradation mechanisms must be managed and suppressed through development of advanced epitaxial and surface passivation techniques in order to fully exploit the robustness of the III-nitride material system. Of the research level devices without dielectric layer surface capping, InAlN HEMTs exhibited the greater stability compared with AlGaN under off-state bias stressing and gamma irradiation in terms of their DC characteristics, although AlGaN HEMTs had significantly higher breakdown voltages. The effect of plasma-enhanced chemical vapour deposition SiNx surface capping is explored, highlighting the sensitivity of InAlN HEMT performance to surface passivation techniques. InAlN-SiNx HEMTs suffered more from trap related degradation than AlGaN-SiNx devices in terms of radiation hardness and step-stress characteristics, attributed to an increased capturing of carriers in traps at the InAlN/SiNx interface.

  10. Stochastic Simulations of Clusters: Quantum Methods in Flat and Curved Spaces. By Emanuele Curotto, CRC Press, 2010; 696 pages, Hard Cover. Price: $159.95 / CHF 257.00 ISBN 978-1-4200-8225-8

    Shu-Kun Lin


    Full Text Available Clusters hold the key to our understanding of intermolecular forces and how these affect the physical properties of bulk condensed matter. They can be found in a multitude of important applications, including novel fuel materials, atmospheric chemistry, semiconductors, nanotechnology, and computational biology. Focusing on the class of weakly bound substances known as van derWaals clusters or complexes, Stochastic Simulations of Clusters: Quantum Methods in Flat and Curved Spaces presents advanced quantum simulation techniques for condensed matter. [...

  11. Photon technology. Hard photon technology; Photon technology. Hard photon gijutsu



    Research results of hard photon technology have been summarized as a part of novel technology development highly utilizing the quantum nature of photon. Hard photon technology refers to photon beam technologies which use photon in the 0.1 to 200 nm wavelength region. Hard photon has not been used in industry due to the lack of suitable photon sources and optical devices. However, hard photon in this wavelength region is expected to bring about innovations in such areas as ultrafine processing and material synthesis due to its atom selective reaction, inner shell excitation reaction, and spatially high resolution. Then, technological themes and possibility have been surveyed. Although there are principle proposes and their verification of individual technologies for the technologies of hard photon generation, regulation and utilization, they are still far from the practical applications. For the photon source technology, the laser diode pumped driver laser technology, laser plasma photon source technology, synchrotron radiation photon source technology, and vacuum ultraviolet photon source technology are presented. For the optical device technology, the multi-layer film technology for beam mirrors and the non-spherical lens processing technology are introduced. Also are described the reduction lithography technology, hard photon excitation process, and methods of analysis and measurement. 430 refs., 165 figs., 23 tabs.

  12. Characterization of Input Current Interharmonics in Adjustable Speed Drives

    Soltani, Hamid; Davari, Pooya; Zare, Firuz


    -edge symmetrical regularly sampled Space Vector Modulation (SVM) technique, on the input current interharmonic components are presented and discussed. Particular attention is also given to the influence of the asymmetrical regularly sampled modulation technique on the drive input current interharmonics...

  13. Unified approach to hard diffraction

    Peschanski, R


    Using a combination of S-Matrix and perturbative QCD properties in the small x_{Bj} regime, we propose a formulation of hard diffraction unifying the partonic (Ingelman-Schlein) Pomeron, Soft Colour Interaction and QCD dipole descriptions.

  14. Driving anger in Malaysia.

    Sullman, Mark J M; Stephens, Amanda N; Yong, Michelle


    The present study examined the types of situations that cause Malaysian drivers to become angry. The 33-item version of the driver anger scale (Deffenbacher et al., 1994) was used to investigate driver anger amongst a sample of 339 drivers. Confirmatory factor analysis showed that the fit of the original six-factor model (discourtesy, traffic obstructions, hostile gestures, slow driving, illegal driving and police presence), after removing one item and allowing three error pairs to covary, was satisfactory. Female drivers reported more anger, than males, caused by traffic obstruction and hostile gestures. Age was also negatively related to five (discourtesy, traffic obstructions, hostile gestures, slow driving and police presence) of the six factors and also to the total DAS score. Furthermore, although they were not directly related to crash involvement, several of the six forms of driving anger were significantly related to the crash-related conditions of: near misses, loss of concentration, having lost control of a vehicle and being ticketed. Overall the pattern of findings made in the present research were broadly similar to those from Western countries, indicating that the DAS is a valid measure of driving anger even among non-European based cultures.

  15. Information Leakage Prevention Using Virtual Disk Drive

    Tarek S. Sobh


    Full Text Available The worst news for information technology people are computer has been stolen or lost. The actual problem is the loss of the data stored on the hard drive that can fall into the wrong hands. However, users of information system and laptops computers are facing real problems with due to intruders using attack techniques when they are connected to the network and lost or stolen computers. In order to protect your organization against information leakage you should encrypt this data by only allowing the user with access to the encryption key to view the data, authorized application usage, and control who gets access to specific types of data. This work focuses on confidentiality of secure information storage. In addition, it presents the model to create of a Virtual Disk Drive (VDD on MS Windows, that appear to the user (after the mounting process as hard disks, but that are really stored as ciphered files on a file system. The proposed VDD prevents dictionary attacks and brute force attacks by incorporating a CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart in the login mechanism. The authentication method for the VDD login is based upon a 3-D image CAPTCHA. All components of this work are integrated in one security VDD tool called "SecDisk".

  16. Barrel wear reduction in rail guns: the effects of known and controlled rail spacing on low voltage electrical contact and the hard chrome plating of copper-tungsten rail and pure copper rails

    McNeal, Cedric J.


    Approved for public release, distribution is unlimited 100 m/s). Low voltage electrical contact was not maintained for some experimental shots and non-parallel rails were the suspected cause. In this thesis, we used a non-contact capacitive sensor to determine rail spacing to within 2/kAcm10mael, so that the rails will be parallel within small tolerances. Several rails were used in these experiments: 75-25 copper-tungsten, chromium-plated 75-25 Cu-W, and chromium-plated pure copper rails. ...

  17. U.S. DRIVE



    U.S. DRIVE, which stands for United States Driving Research and Innovation for Vehicle efficiency and Energy sustainability, is an expanded government-industry partnership among the U.S. Department of Energy; USCAR, representing Chrysler Group LLC, Ford Motor Company and General Motors; Tesla Motors; five energy companies – BP America, Chevron Corporation, ConocoPhillips, ExxonMobil Corporation, and Shell Oil Products US; two utilities – Southern California Edison and Michigan-based DTE Energy; and the Electric Power Research Institute (EPRI). The U.S. DRIVE mission is to accelerate the development of pre-competitive and innovative technologies to enable a full range of affordable and clean advanced light-duty vehicles, as well as related energy infrastructure.

  18. Power converters and AC electrical drives with linear neural networks

    Cirrincione, Maurizio


    The first book of its kind, Power Converters and AC Electrical Drives with Linear Neural Networks systematically explores the application of neural networks in the field of power electronics, with particular emphasis on the sensorless control of AC drives. It presents the classical theory based on space-vectors in identification, discusses control of electrical drives and power converters, and examines improvements that can be attained when using linear neural networks. The book integrates power electronics and electrical drives with artificial neural networks (ANN). Organized into four parts,

  19. Toyota hybrid synergy drive

    Gautschi, H.


    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  20. Toyota hybrid synergy drive

    Gautschi, H.


    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  1. Gears and gear drives

    Jelaska, Damir T


    Understanding how gears are formed and how they interact or 'mesh' with each other is essential when designing equipment that uses gears or gear trains. The way in which gear teeth are formed and how they mesh is determined by their geometry and kinematics, which is the topic of this book.  Gears and Gear Drives provides the reader with comprehensive coverage of gears and gear drives. Spur, helical, bevel, worm and planetary gears are all covered, with consideration given to their classification, geometry, kinematics, accuracy control, load capacity and manufacturing. Cylindric

  2. Microlinear piezo drive experiments

    Azin, A. V.; Bogdanov, E. P.; Rikkonen, S. V.; Ponomarev, S. V.; Khramtsov, A. M.


    The article embraces the experimental description of the micro linear piezo drive intended for the peripheral cord tensioner in the reflecting surface shape regulator system for large-sized transformable spacecraft antenna reflectors. The research target is the experimental investigation of the micro linear piezo drive to determine the stable oscillatory system operating modes which would include improved energy conversion parameters. The following points are briefly presented: test stand construction-design of the peripheral cord tensioner; the determined frequency characteristics and the identified resonant and actual frequencies of an oscillatory system under inertia load. A series of experiments has been conducted for both different preliminary voltages and inertia mass values.

  3. Dangers of Texting While Driving

    ... . Print Out Texting While Driving Guide (pdf) File a Complaint with the FCC ... Office: Consumer and Governmental Affairs Tags: Consumers - Distracted Driving - Health and Safety - Texting Federal Communications Commission 445 12th Street SW, Washington, ...

  4. Strong path convergence from Loewner driving convergence

    Sheffield, Scott


    We show that, under mild assumptions on the limiting curve, a sequence of simple chordal planar curves converges uniformly whenever certain Loewner driving functions converge. We extend this result to random curves. The random version applies in particular to random lattice paths that have chordal SLE as a scaling limit, with kappa less than 8 (non-space-filling). Existing SLE convergence proofs often begin by showing that the Loewner driving functions of these paths (viewed from infinity) converge to Brownian motion. Unfortunately, this is not sufficient, and additional arguments are required to complete the proofs. We show that driving function convergence is sufficient if it can be established for both parametrization directions and a generic target.

  5. Calibration of a time-resolved hard-x-ray detector using radioactive sources

    Stoeckl, C.; Theobald, W.; Regan, S. P.; Romanofsky, M. H.


    A four-channel, time-resolved, hard x-ray detector (HXRD) has been operating at the Laboratory for Laser Energetics for more than a decade. The slope temperature of the hot-electron population in direct-drive inertial confinement fusion experiments is inferred by recording the hard x-ray radiation generated in the interaction of the electrons with the target. Measuring the energy deposited by hot electrons requires an absolute calibration of the hard x-ray detector. A novel method to obtain an absolute calibration of the HXRD using single photons from radioactive sources was developed, which uses a thermoelectrically cooled, low-noise, charge-sensitive amplifier.

  6. Novel drive mechanism for in-tube micro robots

    CHEN Yangzhi; XING Guangquan; PENG Xuefei; LIU Wenguang; YAO Huaping


    The volume of an in-tube micro robot is small and its interior space is very limited. However, conventional transmission methods are unfit to drive in-tube micro robots. A novel micro drive mechanism called the micro-elastic- meshing-wheel is presented in this paper. It can be used for transmitting power and locomotion between two shafts, which are upright and cross in a micro space. The mechanical model of the novel drive mechanism is built, and the maximal trans- mission force is deduced. Then, sufficient experiments are carried out to test maximal transmission force produced by the novel drive mechanism. The calculation and experiment results show that the novel drive mechanism can transmit sufficient power to in-tube micro robots.

  7. Chaos in drive systems

    Kratochvíl C.


    Full Text Available The purpose of this article is to provide an elementary introduction to the subject of chaos in the electromechanical drive systems. In this article, we explore chaotic solutions of maps and continuous time systems. These solutions are also bounded like equilibrium, periodic and quasiperiodic solutions.

  8. Fresh Drive Against Corruption


    China’s government is making efforts to prevent corruption by taking harsh measures against the illegal selection and appointment of cadres on the 10th anniversary of China’s anti-corruption drive,President Hu Jintao called fogreater efforts to carry it out.

  9. Driving with a Goat



    <正>A highway patrol officer was sitting in his car beside the road one day when he noticed a man driving with a goat in the back seat of his car.Turning on the lights,he pulled out,sped up, and pulled the man over.

  10. Drugs and driving

    Walsh, J. Michael; De Gier, Johan J.; Christopherson, Asbjørg S.; Verstraete, Alain G.


    The authors present a global overview on the issue of drugs and driving covering four major areas: (1) Epidemiology and Prevalence-which reviews epidemiological research, summarizes available information, discusses the methodological shortcomings of extant studies, and makes recommendations for futu

  11. Drive-Through Training

    Carter, Margie


    In this article, the author discusses how the early childhood field's approach to staff training reflects the drive-through, fast-food culture. Year after year directors send their teachers to workshops to get some quick refresher techniques. The author suggests that rather than focusing professional development on topics, focus on observing…

  12. The Drive to Influence

    Rodriguez, Diego


    At the heart of the educational vocation is a drive to influence, to meaningfully affect the learning and development of others. For adult educators working in higher education, daily activities--from teaching classes to supervising student research to attending faculty meetings to sitting on advisory boards--are full of opportunities to…

  13. Driving While Intoxicated.

    Brick, John

    Alcohol intoxication increases the risk of highway accidents, the relative risk of crash probability increasing as a function of blood alcohol content (BAC). Because alcohol use is more prevalent than use of other drugs, more is known about the relationship between alcohol use and driving. Most states presume a BAC of .10% to be evidence of drunk…

  14. Gaze-controlled Driving

    Tall, Martin; Alapetite, Alexandre; San Agustin, Javier


    We investigate if the gaze (point of regard) can control a remote vehicle driving on a racing track. Five different input devices (on-screen buttons, mouse-pointing low-cost webcam eye tracker and two commercial eye tracking systems) provide heading and speed control on the scene view transmitted...

  15. Electric-Drive Vehicles

    Septon, Kendall K [National Renewable Energy Laboratory (NREL), Golden, CO (United States)


    Electric-drive vehicles use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. These vehicles can be divided into three categories: Hybrid electric vehicles (HEVs), Plug-in hybrid electric vehicles (PHEVs), All-electric vehicles (EVs). Together, PHEVs and EVs can also be referred to as plug-in electric vehicles (PEVs).


    J. Musil


    The article reviews the present state of the art in the magnetron sputtering of hart and superhard nanocomposite coatings. It is shown that there are (1) two groups of hard and superhard nanocomposites: (i) nc-MN/hard phase and (ii) nc-MN/soft phase, (2) three possible origins of the enhanced hardness: (i) dislocation-dominated plastic deformation, (ii) cohesive forces between atoms and (iii) nanostructure of materials, and (3) huge differences in the microstructure of single- and two-phase films. A main attention is devoted to the formation of nanocrystalline and/or X-ray amorphous films. Such films are created in a vicinity of transitions between (i)crystalline and amorphous phases, (ii) two crystalline phases of different chemical composition or (iii) two different preferred orientations of grains of the sane material from which the coating is composed. The existence of the last transition makes it possible to explain the enhanced hardness in single-phase films. The thermal stability and oxidation resistance of hard nanocomposite films is also shortly discussed.

  17. Age, skill, and hazard perception in driving.

    Borowsky, Avinoam; Shinar, David; Oron-Gilad, Tal


    This study examined the effects of age and driving experience on the ability to detect hazards while driving; namely, hazard perception. Studies have shown that young-inexperienced drivers are more likely than experienced drivers to suffer from hazard perception deficiencies. However, it remains to be determined if this skill deteriorates with advancing age. Twenty-one young-inexperienced, 19 experienced, and 16 elderly drivers viewed six hazard perception movies while connected to an eye tracking system and were requested to identify hazardous situations. Four movies embedded planned, highly hazardous, situations and the rest were used as control. Generally, experienced and older-experienced drivers were equally proficient at hazard detection and detected potentially hazardous events (e.g., approaching an intersection, pedestrians on curb) continuously whereas young-inexperienced drivers stopped reporting on hazards that followed planned, highly hazardous situations. Moreover, while approaching T intersections older and experienced drivers fixated more towards the merging road on the right while young-inexperienced drivers fixated straight ahead, paying less attention to potential vehicles on the merging road. The study suggests that driving experience improves drivers' awareness of potential hazards and guides drivers' eye movements to locations that might embed potential risks. Furthermore, advanced age hardly affects older drivers' ability to perceive hazards, and older drivers are at least partially aware of their age-related limitations. Copyright 2010 Elsevier Ltd. All rights reserved.

  18. Development and application prospects of piezoelectric precision driving technology


    With the rapid development of science and technology,microelectronics manufacturing,photonics technology,space technology,ultra-precision machining,micro-robotics,biomedical engineering and other fields urgently need the support of modern precision driving theory and technology.Modern precision driving technology can be generally divided into two parts:electromagnetic and non-electromagnetic driving technology.Electromagnetic driving technology is based on traditional technology,has a low thrust-weight ratio,and needs deceleration devices with a cumbrous system or a complex structure.Moreover,it is difficult to improve positioning accuracy with this technology type.Thus,electromagnetic driving technology is still unable to meet the requirements for the above applications.Non-electromagnetic driving technology is a new choice.As a category of non-electromagnetic driving technology,piezoelectric driving technology becomes an important branch of modern precision driving technology.High holding torque and acute response make it suitable as an accurate positioning actuator.This paper presents the development of piezoelectric precision driving technology at home and abroad and gives an in-depth analysis.Future perspectives on the technology's applications in the following fields are described:1) integrated circuit manufacturing technology;2) fiber optic component manufacturing technology;3) micro parts manipulation and assembly technology;4) biomedical engineering;5)aerospace technology;and 6) ultra-precision processing technology.

  19. Hard Diffraction at D{phi}

    Alves, Gilvan A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Lab. de Cosmologia e Fisica Experimental de Altas Energias


    Full text follows: We review recent Hard Diffraction results from the D{phi} experiment at Fermilab, for the following processes: hard color singlet exchange, hard single diffraction, and hard double pomeron exchange. Measurements of rates, {eta}, E{sub T} and {radical}S dependencies are presented and comparisons made with predictions of several models. (author)

  20. Photon technology. Hard photon technology; Photon technology. Hard photon gijutsu



    For the application of photon to industrial technologies, in particular, a hard photon technology was surveyed which uses photon beams of 0.1-200nm in wavelength. Its features such as selective atom reaction, dense inner shell excitation and spacial high resolution by quantum energy are expected to provide innovative techniques for various field such as fine machining, material synthesis and advanced inspection technology. This wavelength region has been hardly utilized for industrial fields because of poor development of suitable photon sources and optical devices. The developmental meaning, usable time and issue of a hard photon reduction lithography were surveyed as lithography in ultra-fine region below 0.1{mu}m. On hard photon analysis/evaluation technology, the industrial use of analysis, measurement and evaluation technologies by micro-beam was viewed, and optimum photon sources and optical systems were surveyed. Prediction of surface and surface layer modification by inner shell excitation, the future trend of this process and development of a vacuum ultraviolet light source were also surveyed. 383 refs., 153 figs., 17 tabs.

  1. Hard Diffraction in Pythia 8

    Rasmussen, Christine O


    We present an overview of the options for diffraction implemented in the general--purpose event generator Pythia 8. We review the existing model for low-- and high--mass soft diffraction and present a new model for hard diffraction in pp and ppbar collisions. Both models uses the Pomeron approach pioneered by Ingelman and Schlein, factorising the single diffractive cross section into a Pomeron flux and a Pomeron PDF. The model for hard diffraction is implemented as a part of the multiparton interactions framework, thereby introducing a dynamical rapidity gap survival probability that explicitly breaks factorisation.

  2. Hard Diffraction in Pythia 8

    Rasmussen, Christine O


    We present an overview of the options for diffraction implemented in the general-purpose event generator Pythia 8. We review the existing model for soft diffraction and present a new model for hard diffraction. Both models use the Pomeron approach pioneered by Ingelman and Schlein, factorising the diffractive cross section into a Pomeron flux and a Pomeron PDF, with several choices for both implemented in Pythia 8. The model of hard diffraction is implemented as a part of the multiparton interactions (MPI) framework, thus introducing a dynamical gap survival probability that explicitly breaks factorisation.

  3. Hard diffraction in Pythia 8

    Overgaard Rasmussen, Christine


    We present an overview of the options for diffraction implemented in the general-purpose event generator Pythia 8 [1]. We review the existing model for soft diffraction and present a new model for hard diffraction. Both models use the Pomeron approach pioneered by Ingelman and Schlein, factorising the diffractive cross section into a Pomeron flux and a Pomeron PDF, with several choices for both implemented in Pythia 8. The model of hard diffraction is implemented as a part of the multiparton interactions (MPI) framework, thus introducing a dynamical gap survival probability that explicitly breaks factorisation.

  4. Rad-hard Location and Attitude Module (R-LAM) Project

    National Aeronautics and Space Administration — R-LAM (Rad-hard Location and Attitude Module), promises a new generation of both integrated navigation modules and stand-alone navigation subsystems including...

  5. Uncooled Radiation Hard SiC Schottky VUV Detectors Capable of Single Photon Sensing Project

    National Aeronautics and Space Administration — This project seeks to design, fabricate, characterize and commercialize very large area, uncooled and radiative hard 4H-SiC VUV detectors capable of near single...

  6. Wide Temperature Rad-Hard ASIC for Process Control of a Fuel Cell System Project

    National Aeronautics and Space Administration — Ridgetop Group developed a top-level design of a rad-hard application-specific integrated circuit (ASIC) for spacecraft power management that is functional over a...

  7. Driving and engine cycles

    Giakoumis, Evangelos G


    This book presents in detail the most important driving and engine cycles used for the certification and testing of new vehicles and engines around the world. It covers chassis and engine-dynamometer cycles for passenger cars, light-duty vans, heavy-duty engines, non-road engines and motorcycles, offering detailed historical information and critical review. The book also provides detailed examples from SI and diesel engines and vehicles operating during various cycles, with a focus on how the engine behaves during transients and how this is reflected in emitted pollutants, CO2 and after-treatment systems operation. It describes the measurement methods for the testing of new vehicles and essential information on the procedure for creating a driving cycle. Lastly, it presents detailed technical specifications on the most important chassis-dynamometer cycles around the world, together with a direct comparison of those cycles.

  8. Driving on the Descartes


    Astronaut John W. Young, Apollo 16 mission commander, drives the 'Rover', Lunar Roving Vehicle (LRV) to its final parking place near the end of the third extravehicular activity (EVA-3) at the Descartes landing site. Astronaut Charles M. Duke Jr., Lunar Module pilot, took this photograph looking southward. The flank of Stone Mountain can be seen on the horizon at left. The shadow of the Lunar Module 'Orion' is visible in the foreground.

  9. Managing Ethiopian Cities II: Informality in Ethiopia: Taxing the Hard to Tax

    A. Bongwa (Aloysius)


    textabstractLarge informal (hard to tax) sectors are an integral part of the economies of developing countries (Ethiopia included). In much of Africa, the informal, or gray economy that escapes tax collectors and government regulators, is the hidden dynamic driving economic growth. The informal econ

  10. Hard Trying and These Recipes

    Atwell, Nancie


    Writers thrive when they are motivated to work hard, have regular opportunities to practice and reflect, and benefit from a knowledgeable teacher who knows writing. Student feedback to lessons during writing workshop helped guide Nancie Atwell in her quest to provide the richest and most efficient path to better writing.

  11. Kinetic theory of hard spheres

    Beijeren, H. van; Ernst, M.H.


    Kinetic equations for the hard-sphere system are derived by diagrammatic techniques. A linear equation is obtained for the one-particle-one particle equilibrium time correlation function and a nonlinear equation for the one-particle distribution function in nonequilibrium. Both equations are nonloca

  12. Metrics for Hard Goods Merchandising.

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in hard goods merchandising, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  13. Inclusive Hard Diffraction at HERA

    Proskuryakov, Alexander


    Recent data from the H1 and ZEUS experiments on hard inclusive diffraction are discussed. Results of QCD analyses of the diffractive deep-inelastic scattering processes are reported. Predictions based on the extracted parton densities are compared to diffractive dijet measurements.

  14. Hard sphere packings within cylinders.

    Fu, Lin; Steinhardt, William; Zhao, Hao; Socolar, Joshua E S; Charbonneau, Patrick


    Arrangements of identical hard spheres confined to a cylinder with hard walls have been used to model experimental systems, such as fullerenes in nanotubes and colloidal wire assembly. Finding the densest configurations, called close packings, of hard spheres of diameter σ in a cylinder of diameter D is a purely geometric problem that grows increasingly complex as D/σ increases, and little is thus known about the regime for D > 2.873σ. In this work, we extend the identification of close packings up to D = 4.00σ by adapting Torquato-Jiao's adaptive-shrinking-cell formulation and sequential-linear-programming (SLP) technique. We identify 17 new structures, almost all of them chiral. Beyond D ≈ 2.85σ, most of the structures consist of an outer shell and an inner core that compete for being close packed. In some cases, the shell adopts its own maximum density configuration, and the stacking of core spheres within it is quasiperiodic. In other cases, an interplay between the two components is observed, which may result in simple periodic structures. In yet other cases, the very distinction between the core and shell vanishes, resulting in more exotic packing geometries, including some that are three-dimensional extensions of structures obtained from packing hard disks in a circle.

  15. Hard sphere model of atom

    Tsekov, R


    The finite size effect of electron and nucleus is accounted for in the model of atom. Due to their hard sphere repulsion the energy of the 1s orbital decreases and the corrections amount up to 8 % in Uranium. Several models for boundary conditions on the atomic nucleus surface are discussed as well.

  16. Stress in hard metal films

    Janssen, G.C.A.M.; Kamminga, J.D.


    In the absence of thermal stress, tensile stress in hard metal films is caused by grain boundary shrinkage and compressive stress is caused by ion peening. It is shown that the two contributions are additive. Moreover tensile stress generated at the grain boundaries does not relax by ion bombardment

  17. Unifying approach to hard diffraction

    Navelet, H


    We find a formulation of hard diffraction unifying the partonic (Ingelman-Schlein) Pomeron, Soft Colour Interaction and QCD dipole descriptions. A theoretical interpretation in terms of S-Matrix and perturbative QCD properties in the small x_{Bj} regime is proposed.

  18. Verrucous Carcinoma of Hard Plate

    Parmod Kalstra,Monica Manhas,Rajdeep Sood


    VerrucouS squamous cell carcinoma occurs mainly in oral cavity and larynx, buccal mucosa being most commonly involved. One case of verrucous carcinoma involvmg left hard palate (T4 No Mo)in an adult male is being reported who underwent left total maxillectomy. The tumor behaviour andlts management has been dlscussed.

  19. Microsatellite Direct Drive SEP Module for Interplanetary Exploration via Rideshare Project

    National Aeronautics and Space Administration — Solar Electric Propulsion drives down the cost of space missions by using its high propulsion efficiency to step down from one launch class to another. As launch...

  20. Hard x-ray telescope mission

    Gorenstein, P.; Worrall, D.; Joensen, K.D.


    The Hard X-Ray Telescope was selected for study as a possible new intermediate size mission for the early 21st century. Its principal attributes are: (1) multiwavelength observing with a system of focussing telescopes that collectively observe from the UV to over 1 MeV, (2) much higher sensitivity...... and much better angular resolution in the 10 - 100 keV band, and (3) higher sensitivity for detecting gamma ray lines of known energy in the 100 keV to 1 MeV band. This paper emphasizes the mission aspects of the concept study such as the payload configuration and launch vehicle. An engineering team...... at the Marshall Space Center is participating in these two key aspects of the study....

  1. Explicit Optimal Hardness via Gaussian stability results

    De, Anindya


    The results of Raghavendra (2008) show that assuming Khot's Unique Games Conjecture (2002), for every constraint satisfaction problem there exists a generic semi-definite program that achieves the optimal approximation factor. This result is existential as it does not provide an explicit optimal rounding procedure nor does it allow to calculate exactly the Unique Games hardness of the problem. Obtaining an explicit optimal approximation scheme and the corresponding approximation factor is a difficult challenge for each specific approximation problem. An approach for determining the exact approximation factor and the corresponding optimal rounding was established in the analysis of MAX-CUT (KKMO 2004) and the use of the Invariance Principle (MOO 2005). However, this approach crucially relies on results explicitly proving optimal partitions in Gaussian space. Until recently, Borell's result (Borell 1985) was the only non-trivial Gaussian partition result known. In this paper we derive the first explicit optimal...

  2. Hard and Soft Sub-Time-Optimal Robust Controllers

    Kulczycki, Piotr; Wisniewski, Rafal; Kowalski, Piotr


    has been treated as a stochastic process, is presented in this paper. As a result, through a generalization of the classic switching curve occurring in the time-optimal approach, two control structures have been investigated: the hard, defined on the basis of the rules of the statistical decision...... theory, and also the soft, which additionally allows the elimination of rapid changes in control values. The methodology proposed here may be easily adopted for other elements commonly found in mechanical systems, e.g. parameters of drive or motion resistance, giving the sub-time-optimal controlling...

  3. Radiation-hard/high-speed parallel optical links

    Gan, K.K., E-mail: [Department of Physics, The Ohio State University, Columbus, OH 43210 (United States); Buchholz, P.; Heidbrink, S. [Fachbereich Physik, Universität Siegen, Siegen (Germany); Kagan, H.P.; Kass, R.D.; Moore, J.; Smith, D.S. [Department of Physics, The Ohio State University, Columbus, OH 43210 (United States); Vogt, M.; Ziolkowski, M. [Fachbereich Physik, Universität Siegen, Siegen (Germany)


    We have designed and fabricated a compact parallel optical engine for transmitting data at 5 Gb/s. The device consists of a 4-channel ASIC driving a VCSEL (Vertical Cavity Surface Emitting Laser) array in an optical package. The ASIC is designed using only core transistors in a 65 nm CMOS process to enhance the radiation-hardness. The ASIC contains an 8-bit DAC to control the bias and modulation currents of the individual channels in the VCSEL array. The performance of the optical engine up at 5 Gb/s is satisfactory.

  4. Radiation-hard/high-speed parallel optical links

    Gan, K. K.; Buchholz, P.; Heidbrink, S.; Kagan, H. P.; Kass, R. D.; Moore, J.; Smith, D. S.; Vogt, M.; Ziolkowski, M.


    We have designed and fabricated a compact parallel optical engine for transmitting data at 5 Gb/s. The device consists of a 4-channel ASIC driving a VCSEL (Vertical Cavity Surface Emitting Laser) array in an optical package. The ASIC is designed using only core transistors in a 65 nm CMOS process to enhance the radiation-hardness. The ASIC contains an 8-bit DAC to control the bias and modulation currents of the individual channels in the VCSEL array. The performance of the optical engine up at 5 Gb/s is satisfactory.

  5. Brownian dynamics simulations with hard-body interactions: Spherical particles

    Behringer, Hans; 10.1063/1.4761827


    A novel approach to account for hard-body interactions in (overdamped) Brownian dynamics simulations is proposed for systems with non-vanishing force fields. The scheme exploits the analytically known transition probability for a Brownian particle on a one-dimensional half-line. The motion of a Brownian particle is decomposed into a component that is affected by hard-body interactions and into components that are unaffected. The hard-body interactions are incorporated by replacing the affected component of motion by the evolution on a half-line. It is discussed under which circumstances this approach is justified. In particular, the algorithm is developed and formulated for systems with space-fixed obstacles and for systems comprising spherical particles. The validity and justification of the algorithm is investigated numerically by looking at exemplary model systems of soft matter, namely at colloids in flow fields and at protein interactions. Furthermore, a thorough discussion of properties of other heurist...

  6. Multicomponent fluid of nonadditive hard spheres near a wall.

    Fantoni, Riccardo; Santos, Andrés


    A recently proposed rational-function approximation [Phys. Rev. E 84, 041201 (2011)] for the structural properties of nonadditive hard spheres is applied to evaluate analytically (in Laplace space) the local density profiles of multicomponent nonadditive hard-sphere mixtures near a planar nonadditive hard wall. The theory is assessed by comparison with NVT Monte Carlo simulations of binary mixtures with a size ratio 1:3 in three possible scenarios: a mixture with either positive or negative nonadditivity near an additive wall, an additive mixture with a nonadditive wall, and a nonadditive mixture with a nonadditive wall. It is observed that, while the theory tends to underestimate the local densities at contact (especially in the case of the big spheres) it captures very well the initial decay of the densities with increasing separation from the wall and the subsequent oscillations.

  7. Hard processes in hadronic interactions

    Satz, H. [CERN, Geneva (Switzerland)]|[Universitat Bielefeld (Germany); Wang, X.N. [Lawrence Berkeley Lab., CA (United States)


    Quantum chromodynamics is today accepted as the fundamental theory of strong interactions, even though most hadronic collisions lead to final states for which quantitative QCD predictions are still lacking. It therefore seems worthwhile to take stock of where we stand today and to what extent the presently available data on hard processes in hadronic collisions can be accounted for in terms of QCD. This is one reason for this work. The second reason - and in fact its original trigger - is the search for the quark-gluon plasma in high energy nuclear collisions. The hard processes to be considered here are the production of prompt photons, Drell-Yan dileptons, open charm, quarkonium states, and hard jets. For each of these, we discuss the present theoretical understanding, compare the resulting predictions to available data, and then show what behaviour it leads to at RHIC and LHC energies. All of these processes have the structure mentioned above: they contain a hard partonic interaction, calculable perturbatively, but also the non-perturbative parton distribution within a hadron. These parton distributions, however, can be studied theoretically in terms of counting rule arguments, and they can be checked independently by measurements of the parton structure functions in deep inelastic lepton-hadron scattering. The present volume is the work of Hard Probe Collaboration, a group of theorists who are interested in the problem and were willing to dedicate a considerable amount of their time and work on it. The necessary preparation, planning and coordination of the project were carried out in two workshops of two weeks` duration each, in February 1994 at CERn in Geneva andin July 1994 at LBL in Berkeley.

  8. 空间润滑谐波减速器传动性能正交试验分析%Orthogonal Experiment Analysis on Transmission Performance of Space Lubricated Harmonic Drive



    Thermal-vacuum tests are performed to evaluate the transmission performance of solid and grease lubricated XB1-60-150 harmonic drive. The effects of ambient temperature, output load, lubrication type, and operation time on the transmission performance of the harmonic drive are investigated based on orthogonal design method for multi-factor analysis, when the transmission efficiency is taken into account as an evaluation index. The transmission performance of the solid and grease lubricated harmonic drivers is studied under a range of temperature and rated load condition. The relationship of transmission efficiency of those to temperature and operation time is analyzed. After running 1.5*105 r of the wave generator, the morphologies of the gear teeth and the inner surface of the flexspline under different lubrication type are analyzed by using an optical microscope. It is found that the most important influencing factor on the transmission performance is temperature and the least important influencing factor is operation time. Lubrication type and output load are less important factors. In the temperature range of -40 ℃ to 60 ℃, the transmission efficiency of grease lubricated harmonic drive is better, however, the solid lubricated harmonic drive shows obviously more stable transmission efficiency. The gear teeth and the inner surface of both the solid and grease lubricated harmonic drivers' flexspline show distinct traces of sliding movement after thermally-cycled test.%选用XB1-60-150型谐波减速器,采用多因素正交设计法开展了谐波减速器热真空循环试验,选择传动效率作为传动性能的评价指标,考察环境温度、负载、润滑方式和工作时间等因素对谐波减速器传动性能的影响敏感性;研究额定载荷条件下固体润滑和脂润滑谐波减速器在宽温度范围内的传动性能,探讨传动效率与环境温度、工作时间的关系;在波发生器运行总次数1.5×105 r后,利用光学

  9. Drive system failure control for distributed drive electric vehicles

    Liu, Tao; Tang, Yuan; Wang, Jianfeng; Li, Yaou; Yang, Na; Liu, Yiqun


    Aiming at the failure problem of distributed electric drive vehicle, the conventional control strategy of drive system failure is designed according to the characteristics of each wheel torque independent control and the redundant configuration of the power unit. On this basis, combined with the traditional body stability control technology, the direct yaw moment control method is used. The simulation results show that the conventional control method designed of the drive system failure can effectively improve the driving condition of the vehicle. The driving stability of the vehicle is further improved after the direct yaw torque control is applied.

  10. Long-Life, Oil-Free Polymeric, Multi-Roller Traction Drives for Planetary Vehicle Surface Exploration Project

    National Aeronautics and Space Administration — Multi-roller traction drives have several advantages relative to geared units for aerospace and commercial drive applications. Among these are zero backlash, low...

  11. Performance Analysis of BLDC MLI Drive



    Full Text Available BLDC motors are used in wide range from very small motors used in hard disk drives to large motors used in electric vehicles as it has more advantages over induction motors because it has permanent magnets in rotor assembly generates steady magnetic field. The multilevel inverters are preferred over conventional inverters as the voltage stress across each semiconductor switches is the voltage of one capacitor. The mli gives high voltages with low harmonics and as no of levels increases output tends to sinusoidal. The most used multilevel inverter configurations are diode clamped, flying capacitor, cascaded mli. In this paper five level diode clamped mli, cascaded mli are simulated using MATLAB/SIMULINK. The performance characteristics of bldc motor is observed when fed by each of these configurations.

  12. Offset Compound Gear Drive

    Stevens, Mark A.; Handschuh, Robert F.; Lewicki, David G.


    The Offset Compound Gear Drive is an in-line, discrete, two-speed device utilizing a special offset compound gear that has both an internal tooth configuration on the input end and external tooth configuration on the output end, thus allowing it to mesh in series, simultaneously, with both a smaller external tooth input gear and a larger internal tooth output gear. This unique geometry and offset axis permits the compound gear to mesh with the smaller diameter input gear and the larger diameter output gear, both of which are on the same central, or primary, centerline. This configuration results in a compact in-line reduction gear set consisting of fewer gears and bearings than a conventional planetary gear train. Switching between the two output ratios is accomplished through a main control clutch and sprag. Power flow to the above is transmitted through concentric power paths. Low-speed operation is accomplished in two meshes. For the purpose of illustrating the low-speed output operation, the following example pitch diameters are given. A 5.0 pitch diameter (PD) input gear to 7.50 PD (internal tooth) intermediate gear (0.667 reduction mesh), and a 7.50 PD (external tooth) intermediate gear to a 10.00 PD output gear (0.750 reduction mesh). Note that it is not required that the intermediate gears on the offset axis be of the same diameter. For this example, the resultant low-speed ratio is 2:1 (output speed = 0.500; product of stage one 0.667 reduction and stage two 0.750 stage reduction). The design is not restricted to the example pitch diameters, or output ratio. From the output gear, power is transmitted through a hollow drive shaft, which, in turn, drives a sprag during which time the main clutch is disengaged.

  13. Creating a driving profile for older adults using GPS devices and naturalistic driving methodology

    Babulal, Ganesh M.; Traub, Cindy M.; Webb, Mollie; Stout, Sarah H.; Addison, Aaron; Carr, David B.; Ott, Brian R.; Morris, John C.; Roe, Catherine M.


    Background/Objectives: Road tests and driving simulators are most commonly used in research studies and clinical evaluations of older drivers. Our objective was to describe the process and associated challenges in adapting an existing, commercial, off-the-shelf (COTS), in-vehicle device for naturalistic, longitudinal research to better understand daily driving behavior in older drivers. Design: The Azuga G2 Tracking Device TM was installed in each participant’s vehicle, and we collected data over 5 months (speed, latitude/longitude) every 30-seconds when the vehicle was driven.  Setting: The Knight Alzheimer’s Disease Research Center at Washington University School of Medicine. Participants: Five individuals enrolled in a larger, longitudinal study assessing preclinical Alzheimer disease and driving performance.  Participants were aged 65+ years and had normal cognition. Measurements:  Spatial components included Primary Location(s), Driving Areas, Mean Centers and Unique Destinations.  Temporal components included number of trips taken during different times of the day.  Behavioral components included number of hard braking, speeding and sudden acceleration events. Methods:  Individual 30-second observations, each comprising one breadcrumb, and trip-level data were collected and analyzed in R and ArcGIS.  Results: Primary locations were confirmed to be 100% accurate when compared to known addresses.  Based on the locations of the breadcrumbs, we were able to successfully identify frequently visited locations and general travel patterns.  Based on the reported time from the breadcrumbs, we could assess number of trips driven in daylight vs. night.  Data on additional events while driving allowed us to compute the number of adverse driving alerts over the course of the 5-month period. Conclusions: Compared to cameras and highly instrumented vehicle in other naturalistic studies, the compact COTS device was quickly installed and transmitted high volumes



    在2004年奥林匹克赛事中,中国的李婷,孙甜甜取得了中国网球第一个金牌一女子双打冠军。忘记不了当时李婷挥动着她的BABOLAT(百保力)网拍Pure Drive Zylon 360°激动地拥抱着孙甜甜吵闹着,幸福地哭着的情景。

  15. Electric drive design methodology

    Jufer, Marcel


    An electric drive that is designed or adapted to a specific application must take into account all the elements of the chain of constituent elements in its use and deployment. In addition to the motor, the transmission, power electronics, control, sensors, and electrical protection systems must be taken into account. The motor and the transmission can be optimized and designed to obtain the best energy efficiency assessment, in particular for dynamic nodes. An inventory and a characterization of these various components is proposed as part of this book's examination and explanation

  16. Electrical machines & drives

    Hammond, P


    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

  17. Electrical machines and drives

    Hindmarsh, John


    Recent years have brought substantial developments in electrical drive technology, with the appearance of highly rated, very-high-speed power-electronic switches, combined with microcomputer control systems.This popular textbook has been thoroughly revised and updated in the light of these changes. It retains its successful formula of teaching through worked examples, which are put in context with concise explanations of theory, revision of equations and discussion of the engineering implications. Numerous problems are also provided, with answers supplied.The third edition in

  18. Driving electrostatic transducers

    Nielsen, Dennis; Knott, Arnold; Andersen, Michael A. E.


    Electrostatic transducers represent a very interesting alternative to the traditional inefficient electrodynamic transducers. In order to establish the full potential of these transducers, power amplifiers which fulfill the strict requirements imposed by such loads (high impedance, frequency...... depended, nonlinear and high bias voltage for linearization) must be developed. This paper analyzes power stages and bias configurations suitable for driving an electrostatic transducer. Measurement results of a 300 V prototype amplifier are shown. Measuring THD across a high impedance source is discussed......, and a high voltage attenuation interface for an audio analyzer is presented. THD below 0:1% is reported....

  19. Hard x-ray spectroscopy for proton flare prediction

    Garcia, Howard A.; Farnik, Frantisek; Kiplinger, Alan L.


    High energy interplanetary proton events can jeopardize vital military and civilian spacecraft by disrupting logical circuits and by actually damaging spacecraft electronic components. Studies of solar hard x-rays indicate that high-energy proton events observed near Earth are highly associated with an uncommon type of solar flare exhibiting temporal progressively hardening hard x-ray spectra. A hard x-ray spectrometer is being developed by the Czech Astronomical Institute to provide a test bed for evaluating this phenomenon as a possible proton-storm prediction method. The instrument is designed to measure hard x-ray spectra in a high fluence, high-energy particle background environment such as that found at geosynchronous altitude. This experiment has been selected for space flight by the DoD Space Test Program and will fly aboard the Department of Energy satellite, Multi-spectral thermal Imager, scheduled for a three year mission, beginning in late 1999. The timing of this mission, fortuitously, coincides with the experiment are: 1) to evaluate the efficacy of this type of solar instrument in predicting interplanetary proton storms; 2) to study the high-energy physics of solar flares in concert with the premier flight of the NOAA soft x-ray imaging telescope, SXI, on the GOES 12 weather satellite and other solar mission. If the first goal is demonstrated by this mission, continuous monitoring of the Sun for proton events could become operational from geo-synchronous orbit during solar cycle 24.

  20. General motors front wheel drive 2-mode hybrid transmission

    Hendrickson, James [General Motors Corp., Pontiac, MI (United States). New Transmission Products Group.; Holmes, Alan G. [General Motors Corp., Pontiac, MI (United States). Powertrain Hybrid Architecture


    General Motors now expands the application of two-mode hybrid technology to front wheel drive vehicles with the development of a hybrid electric transmission packaged into essentially the same space as a conventional automatic transmission for front wheel drive. This was accomplished using a space-efficient arrangement based on two planetary gear sets and electric motor-generators with large internal diameters. A combination of damper and hydraulically-controlled clutch allow comfortable shutdown and restarting of large-displacement engines in front wheel drive vehicles. The hybrid system delivers electric low-speed urban driving, two continuously variable ranges of transmission speed ratios, four fixed transmission speed ratios, electric acceleration boosting, and regenerative braking. In the first vehicle application, the two-mode hybrid helps to reduce vehicle fuel consumption by approximately one-third. (orig.)

  1. Text messaging during simulated driving.

    Drews, Frank A; Yazdani, Hina; Godfrey, Celeste N; Cooper, Joel M; Strayer, David L


    This research aims to identify the impact of text messaging on simulated driving performance. In the past decade, a number of on-road, epidemiological, and simulator-based studies reported the negative impact of talking on a cell phone on driving behavior. However, the impact of text messaging on simulated driving performance is still not fully understood. Forty participants engaged in both a single task (driving) and a dual task (driving and text messaging) in a high-fidelity driving simulator. Analysis of driving performance revealed that participants in the dual-task condition responded more slowly to the onset of braking lights and showed impairments in forward and lateral control compared with a driving-only condition. Moreover, text-messaging drivers were involved in more crashes than drivers not engaged in text messaging. Text messaging while driving has a negative impact on simulated driving performance. This negative impact appears to exceed the impact of conversing on a cell phone while driving. The results increase our understanding of driver distraction and have potential implications for public safety and device development.

  2. Molecular hardness and softness, local hardness and softness, hardness and softness kernels, and relations among these quantities

    Berkowitz, Max; Parr, Robert G.


    Hardness and softness kernels η(r,r') and s(r,r') are defined for the ground state of an atomic or molecular electronic system, and the previously defined local hardness and softness η(r) and s(r) and global hardness and softness η and S are obtained from them. The physical meaning of s(r), as a charge capacitance, is discussed (following Huheey and Politzer), and two alternative ``hardness'' indices are identified and briefly discussed.

  3. Ultrasonic material hardness depth measurement

    Good, Morris S.; Schuster, George J.; Skorpik, James R.


    The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part.

  4. Development of Radiation Hard Scintillators

    Tiras, Emrah; Bilki, Burak; Winn, David; Onel, Yasar


    Modern high-energy physics experiments are in ever increasing need for radiation hard scintillators and detectors. In this regard, we have studied various radiation-hard scintillating materials such as Polyethylene Naphthalate (PEN), Polyethylene Terephthalate (PET), our prototype material Scintillator X (SX) and Eljen (EJ). Scintillation and transmission properties of these scintillators are studied using stimulated emission from a 334 nm wavelength UV laser with PMT before and after certain amount of radiation exposure. Recovery from radiation damage is studied over time. While the primary goal of this study is geared for LHC detector upgrades, these new technologies could easily be used for future experiments such as the FCC and ILC. Here we discuss the physics motivation, recent developments and laboratory measurements of these materials.

  5. Turbulent current drive

    Garbet, X.; Esteve, D.; Sarazin, Y.; Dif-Pradalier, G.; Ghendrih, P.; Grandgirard, V.; Latu, G.; Smolyakov, A.


    The Ohm's law is modified when turbulent processes are accounted for. Besides an hyper-resistivity, already well known, pinch terms appear in the electron momentum flux. Moreover it appears that turbulence is responsible for a source term in the Ohm's law, called here turbulent current drive. Two terms contribute to this source. The first term is a residual stress in the momentum flux, while the second contribution is an electro-motive force. A non zero average parallel wave number is needed to get a finite source term. Hence a symmetry breaking mechanism must be invoked, as for ion momentum transport. E × B shear flows and turbulence intensity gradients are shown to provide similar contributions. Moreover this source term has to compete with the collision friction term (resistivity). The effect is found to be significant for a large scale turbulence in spite of an unfavorable scaling with the ratio of the electron to ion mass. Turbulent current drive appears to be a weak effect in the plasma core, but could be substantial in the plasma edge where it may produce up to 10 % of the local current density.

  6. Schwannoma of the hard palate


    Schwannomas are benign encapsulated perineural tumors. The head and neck region is the most common site. Intraoral origin is seen in only 1% of cases, tongue being the most common site; its location in the palate is rare. We report a case of hard-palate schwannoma with bony erosion which was immunohistochemically confirmed. The tumor was excised completely intraorally. After two months of follow-up, the defect was found to be completely covered with palatal mucosa.

  7. Playing Moderately Hard to Get

    Stephen Reysen


    Full Text Available In two studies, we examined the effect of different degrees of attraction reciprocation on ratings of attraction toward a potential romantic partner. Undergraduate college student participants imagined a potential romantic partner who reciprocated a low (reciprocating attraction one day a week, moderate (reciprocating attraction three days a week, high (reciprocating attraction five days a week, or unspecified degree of attraction (no mention of reciprocation. Participants then rated their degree of attraction toward the potential partner. The results of Study 1 provided only partial support for Brehm’s emotion intensity theory. However, after revising the high reciprocation condition vignette in Study 2, supporting Brehm’s emotion intensity theory, results show that a potential partners’ display of reciprocation of attraction acted as a deterrent to participants’ intensity of experienced attraction to the potential partner. The results support the notion that playing moderately hard to get elicits more intense feelings of attraction from potential suitors than playing too easy or too hard to get. Discussion of previous research examining playing hard to get is also re-examined through an emotion intensity theory theoretical lens.

  8. Why Are Drugs So Hard to Quit?

    Full Text Available ... Quitting drugs is hard because addiction is a brain disease. Your brain is like a control tower that sends out ... and choices. Addiction changes the signals in your brain and makes it hard to feel OK without ...

  9. Why Are Drugs So Hard to Quit?

    Full Text Available ... Quitting drugs is hard because addiction is a brain disease. Your brain is like a control tower that sends out ... and choices. Addiction changes the signals in your brain and makes it hard to feel OK without ...

  10. Raman Model Predicting Hardness of Covalent Crystals

    Zhou, Xiang-Feng; Qian, Quang-Rui; Sun, Jian; Tian, Yongjun; Wang, Hui-Tian


    Based on the fact that both hardness and vibrational Raman spectrum depend on the intrinsic property of chemical bonds, we propose a new theoretical model for predicting hardness of a covalent crystal. The quantitative relationship between hardness and vibrational Raman frequencies deduced from the typical zincblende covalent crystals is validated to be also applicable for the complex multicomponent crystals. This model enables us to nondestructively and indirectly characterize the hardness o...

  11. Tribological characterization of selected hard coatings

    Karlsson, Patrik


    Hard coatings are often used for protection of tool surfaces due to coating properties like low friction and high wear resistance. Even though many of the hard coatings have been tested for wear, it is important to try new wear test setups to fully understand tribological mechanisms and the potential of hard coatings. Few experiments have been performed with dual-coated systems where the sliding contact surfaces are coated with the same, or different, hard coating. The dual-coated system coul...

  12. The Driving Factors and the Action Path of the Regional Space of the Production Service Industry Agglomeration%生产性服务业集聚重构区域空间的驱动因素及作用路径

    韩锋; 张永庆; 田家林


    AS our country economy form gradually from the production of goods towards production services , the rapid development of the productive service industry for economic and social development to support and promote the role in an increasing highlight ,the pro-ductive service industry in industrial integration , employment , stable growth has become competition of industry of our country . The strate-gic commanding point and the industrial structure continuously optimize the key power . Producer service industry clusters in the evolution of regional economic development and geographical space plays a huge role in agglomeration and producer services agglomeration effects bring industrial space layout of the reconstruction and regional industrial restructuring , traffic network planning and layout optimization and trans-formation of living space and urban land use types of change and core functional area pattern transfer , the rapid development of productive service industry and cluster agglomeration has become driving force of regional economic space reconstruction strategy to achieve .Producer services agglomeration regional spatial restructuring of the driving factors and path analysis based on the research of new economic geography agglomeration effect on regional economic structure and industry fusion , and space reconstruction evolution mode is of great significance ,to drive factors and the role of path as starting point to research the productive service industry agglomeration reconstruction of the regional space can be in-depth study of agglomeration on regional economic development and regional spatial geographic influence and radiation .%随着我国的经济形态逐步由商品生产迈向服务生产,高速发展的生产性服务业对于经济社会发展的支撑和推动作用日益彰显,生产性服务业在产业融合、吸纳就业、稳定增长等方面发挥重要作用,已经成为我国产业竞争的战略制高点及产业结构不

  13. Putting the Warp into Warp Drive

    Obousy, Richard K


    Over the last decade, there has been a respectable level of scientific interest regarding the concept of a warp drive. This is a hypothetical propulsion device that could theoretically circumvent the traditional limitations of special relativity which restricts spacecraft to sub-light velocities. Any breakthrough in this field would revolutionize space exploration and open the doorway to interstellar travel. This article discusses a novel approach to generating the warp bubble necessary for such propulsion; the mathematical details of this theory are discussed in an article published in the Journal of the British Interpanetary Society. The theory is based on some of the exciting predictions coming out of string theory and it is the aim of this article to introduce the warp drive idea from a non-mathematical perspective that should be accessible to a wide range of readers.

  14. Aligning for Innovation - Alignment Strategy to Drive Innovation

    Johnson, Hurel; Teltschik, David; Bussey, Horace, Jr.; Moy, James


    With the sudden need for innovation that will help the country achieve its long-term space exploration objectives, the question of whether NASA is aligned effectively to drive the innovation that it so desperately needs to take space exploration to the next level should be entertained. Authors such as Robert Kaplan and David North have noted that companies that use a formal system for implementing strategy consistently outperform their peers. They have outlined a six-stage management systems model for implementing strategy, which includes the aligning of the organization towards its objectives. This involves the alignment of the organization from the top down. This presentation will explore the impacts of existing U.S. industrial policy on technological innovation; assess the current NASA organizational alignment and its impacts on driving technological innovation; and finally suggest an alternative approach that may drive the innovation needed to take the world to the next level of space exploration, with NASA truly leading the way.

  15. Aligning for Innovation - Alignment Strategy to Drive Innovation

    Johnson, Hurel; Teltschik, David; Bussey, Horace, Jr.; Moy, James


    With the sudden need for innovation that will help the country achieve its long-term space exploration objectives, the question of whether NASA is aligned effectively to drive the innovation that it so desperately needs to take space exploration to the next level should be entertained. Authors such as Robert Kaplan and David North have noted that companies that use a formal system for implementing strategy consistently outperform their peers. They have outlined a six-stage management systems model for implementing strategy, which includes the aligning of the organization towards its objectives. This involves the alignment of the organization from the top down. This presentation will explore the impacts of existing U.S. industrial policy on technological innovation; assess the current NASA organizational alignment and its impacts on driving technological innovation; and finally suggest an alternative approach that may drive the innovation needed to take the world to the next level of space exploration, with NASA truly leading the way.

  16. 7 CFR 201.21 - Hard seed.


    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Hard seed. 201.21 Section 201.21 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Agricultural Seeds § 201.21 Hard seed. The label shall show the percentage of hard...

  17. 7 CFR 201.30 - Hard seed.


    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Hard seed. 201.30 Section 201.30 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.30 Hard seed. The label shall show the percentage of hard seed,...

  18. Magnetostrictive direct drive motors

    Naik, Dipak; Dehoff, P. H.


    A new rare earth alloy, Terfenol-D, combines low frequency operation and extremely high energy density with high magnetostriction. Its material properties make it suitable as a drive element for actuators requiring high output torque. The high strains, the high forces and the high controllability of Terfenol alloys provide a powerful and challenging basis for new ways to generate motion in actuators. Two prototypes of motors using Terfenol-D rods were developed at NASA Goddard. The basic principles of operation are provided of the motor along with other relevant details. A conceptual design of a torque limiting safety clutch/brake under development is illustrated. Also, preliminary design drawings of a linear actuator using Terfenol-D is shown.


    Sanaz Motamedi


    Full Text Available In an increasingly mobile era, the wide availability of technology for texting and the prevalence of hands-free form have introduced a new safety concern for drivers. To assess this concern, a questionnaire was first deployed online to gain an understanding of drivers’ text driving experiences as well as their demographic information. The results from 232 people revealed that the majority of drivers are aware of the associated risks with texting while driving. However, more than one-fourth of them still frequently send or read text messages while driving. In addition to the questionnaire, through the use of a virtual-reality driving simulator, this study examined drivers’ driving performance while they were engaged in some forms of text driving under different challenging traffic conditions. Through a blocked factorial experiment, drivers would either read a text message or respond to it with two levels of text complexity while using either hand-held or hands-free texting method. Their driving performance was assessed based on the number of driving violations observed in each scenario. Conclusions regarding the impacts of different forms of texting, text complexity, and response mode on drivers driving performance were drawn.

  20. Dimensions of driving anger and their relationships with aberrant driving.

    Zhang, Tingru; Chan, Alan H S; Zhang, Wei


    The purpose of this study was to investigate the relationship between driving anger and aberrant driving behaviours. An internet-based questionnaire survey was administered to a sample of Chinese drivers, with driving anger measured by a 14-item short Driving Anger Scale (DAS) and the aberrant driving behaviours measured by a 23-item Driver Behaviour Questionnaire (DBQ). The results of Confirmatory Factor Analysis demonstrated that the three-factor model (hostile gesture, arrival-blocking and safety-blocking) of the DAS fitted the driving anger data well. The Exploratory Factor Analysis on DBQ data differentiated four types of aberrant driving, viz. emotional violation, error, deliberate violation and maintaining progress violation. For the anger-aberration relation, it was found that only "arrival-blocking" anger was a significant positive predictor for all four types of aberrant driving behaviours. The "safety-blocking" anger revealed a negative impact on deliberate violations, a finding different from previously established positive anger-aberration relation. These results suggest that drivers with different patterns of driving anger would show different behavioural tendencies and as a result intervention strategies may be differentially effective for drivers of different profiles.

  1. Do emotions drive psychosis?

    João Guilherme Ribeiro


    Full Text Available Introduction: How important is the emotional life of persons who manifest psychotic symptoms? Aims: The aim of this paper is to review evidence on a causal role for emotions in psychotic processes. Methods: Selective review of literature on affective symptoms in psychoses, on emotions in the production of psychotic symptoms and on dopaminergic models of psychosis. Results: Affective symptoms are relevant across psychoses. Persons with schizophrenia have high levels of emotional reactivity and the intensification of negative affects not only is associated with but also precedes the intensification of psychotic symptoms, which is evidence that negative emotions drive the course of psychotic symptoms. Negative self‑representations are central in psychotic processes and can be the link between negative emotions and psychosis. Evidence favours the notion that persecutory delusions are consistent with negative affects and self‑representations, while grandiose delusions are consistent with a defensive amplification of positive affects and self‑representations. Shame has been proposed as the core emotional experience of psychosis, one in which the self becomes vulnerable to the external world, which is consistent with persecutory experiences. Assaults on the self, under the form of hostility in the family environment and society, are strong predictors of relapse and development of schizophrenia. Assaults on the self which induce social defeat are also strong stimulants of mesolimbic dopaminergic pathways, whose hyperactivity is associated with acute psychotic episodes and the experience of “aberrant salience”, put forward as a dopaminergic model of psychosis. Conclusions: The “defeat of the self” emerges as a central link that binds the experience of negative emotions to the expression of psychotic symptoms and its psychological and neurobiological correlates. The hypothesis gains support that the emotions related to that defeat control

  2. Do emotions drive psychosis?

    João G. Ribeiro


    Full Text Available Introduction: How important is the emotional life of persons who manifest psychotic symptoms? Aims: The aim of this paper is to review evidence on a causal role for emotions in psychotic processes. Methods: Selective review of literature on affective symptoms in psychoses, on emotions in the production of psychotic symptoms and on dopaminergic models of psychosis. Results: Affective symptoms are relevant across psychoses. Persons with schizophrenia have high levels of emotional reactivity and the intensification of negative affects not only is associated with but also precedes the intensification of psychotic symptoms, which is evidence that negative emotions drive the course of psychotic symptoms. Negative self‑representations are central in psychotic processes and can be the link between negative emotions and psychosis. Evidence favours the notion that persecutory delusions are consistent with negative affects and self‑representations, while grandiose delusions are consistent with a defensive amplification of positive affects and self‑representations. Shame has been proposed as the core emotional experience of psychosis, one in which the self becomes vulnerable to the external world, which is consistent with persecutory experiences. Assaults on the self, under the form of hostility in the family environment and society, are strong predictors of relapse and development of schizophrenia. Assaults on the self which induce social defeat are also strong stimulants of mesolimbic dopaminergic pathways, whose hyperactivity is associated with acute psychotic episodes and the experience of “aberrant salience”, put forward as a dopaminergic model of psychosis. Conclusions: The “defeat of the self” emerges as a central link that binds the experience of negative emotions to the expression of psychotic symptoms and its psychological and neurobiological correlates. The hypothesis gains support that the emotions related to that defeat control

  3. 空间太阳电池阵双轴驱动机构设计及热分析%Design and Thermal Analysis of Space Dual-axis Solar Array Drive Assembly

    李建辉; 李瑞祥; 钱志源


    This paper introduced a lightweight Dual-axis solar array drive assembly (SADA), aiming at two key technologies of lightweight and long life.The Dual-axis SADA consists of A-axis which provides 360° of rotation and power transfer through the use of a slip ring device and B-axis which provides ±90° of travel and incorporates a simple flex loop for power transfer.The accelerated life test of key moving parts of SADA including the slip ring and the harmonic reducer were preformed and passed.The designed principle prototype of SADA has some merits, such as compact structure, good stiffness and light weight.The thermal analysis of the Dual-axis SADA had been preformed.The measures of thermal control are presented by comparing temperature distribution under different schemes.%针对空间太阳电池阵驱动机构的轻量化和长寿命两大关键技术,研制了一种轻小型双轴驱动机构,该机构由连续转动轴(A轴)和有限角度转动轴(B轴)组成,连续转动轴利用导电滑环传输电能,机构具有结构紧凑、刚度好以及重量轻等优点.并通过了包括导电滑环和谐波减速器在内的关键活动部件加速寿命试验考核.利用热分析软件对双轴驱动机构进行了热分析仿真,通过比较不同热控方案下的温度场分布,确定了可以采用的热控措施.

  4. CLIC Drive Beam Phase Stabilisation

    Gerbershagen, Alexander; Schulte, Daniel

    The thesis presents phase stability studies for the Compact Linear Collider (CLIC) and focuses in particular on CLIC Drive Beam longitudinal phase stabilisation. This topic constitutes one of the main feasibility challenges for CLIC construction and is an essential component of the current CLIC stabilisation campaign. The studies are divided into two large interrelated sections: the simulation studies for the CLIC Drive Beam stability, and measurements, data analysis and simulations of the CLIC Test Facility (CTF3) Drive Beam phase errors. A dedicated software tool has been developed for a step-by-step analysis of the error propagation through the CLIC Drive Beam. It uses realistic RF potential and beam loading amplitude functions for the Drive and Main Beam accelerating structures, complete models of the recombination scheme and compressor chicane as well as of further CLIC Drive Beam modules. The tool has been tested extensively and its functionality has been verified. The phase error propagation at CLIC h...

  5. The Drive-Wise Project: Driving Simulator Training increases real driving performance in healthy older drivers

    Gianclaudio eCasutt


    Full Text Available Background: Age-related cognitive decline is often associated with unsafe driving behavior. We hypothesized that 10 active training sessions in a driving simulator increase cognitive and on-road driving performance. In addition, driving simulator training should outperform cognitive training.Methods: Ninety-one healthy active drivers (62 – 87 years were randomly assigned to either (1 a driving simulator training group, (2 an attention training group (vigilance and selective attention, or (3 a control group. The main outcome variables were on-road driving and cognitive performance. Seventy-seven participants (85% completed the training and were included in the analyses. Training gains were analyzed using a multiple regression analysis with planned comparisons.Results: The driving simulator training group showed an improvement in on-road driving performance compared to the attention training group. In addition, both training groups increased cognitive performance compared to the control group. Conclusion: Driving simulator training offers the potential to enhance driving skills in older drivers. Compared to the attention training, the simulator training seems to be a more powerful program for increasing older drivers’ safety on the road.

  6. Driving anger in Ukraine: Appraisals, not trait driving anger, predict anger intensity while driving.

    Stephens, A N; Hill, T; Sullman, M J M


    Trait driving anger is often, but not always, found to predict both the intensity of anger while driving and subsequent crash-related behaviours. However, a number of studies have not found support for a direct relationship between one's tendency to become angry and anger reported while driving, suggesting that other factors may mediate this relationship. The present self-report study investigated whether, in anger provoking driving situations, the appraisals made by drivers influence the relationship between trait and state anger. A sample of 339 drivers from Ukraine completed the 33-item version of the Driver Anger Scale (DAS; Deffenbacher et al., 1994) and eight questions about their most recent experience of driving anger. A structural equation model found that the intensity of anger experienced was predicted by the negative evaluations of the situation, which was in turn predicted by trait driving anger. However, trait driving anger itself did not predict anger intensity; supporting the hypothesis that evaluations of the driving situation mediate the relationship between trait and state anger. Further, the unique structure of the DAS required to fit the data from the Ukrainian sample, may indicate that the anger inducing situations in Ukraine are different to those of a more developed country. Future research is needed to investigate driving anger in Ukraine in a broader sample and also to confirm the role of the appraisal process in the development of driving anger in both developed and undeveloped countries.

  7. The hard problem of cooperation.

    Kimmo Eriksson

    Full Text Available Based on individual variation in cooperative inclinations, we define the "hard problem of cooperation" as that of achieving high levels of cooperation in a group of non-cooperative types. Can the hard problem be solved by institutions with monitoring and sanctions? In a laboratory experiment we find that the answer is affirmative if the institution is imposed on the group but negative if development of the institution is left to the group to vote on. In the experiment, participants were divided into groups of either cooperative types or non-cooperative types depending on their behavior in a public goods game. In these homogeneous groups they repeatedly played a public goods game regulated by an institution that incorporated several of the key properties identified by Ostrom: operational rules, monitoring, rewards, punishments, and (in one condition change of rules. When change of rules was not possible and punishments were set to be high, groups of both types generally abided by operational rules demanding high contributions to the common good, and thereby achieved high levels of payoffs. Under less severe rules, both types of groups did worse but non-cooperative types did worst. Thus, non-cooperative groups profited the most from being governed by an institution demanding high contributions and employing high punishments. Nevertheless, in a condition where change of rules through voting was made possible, development of the institution in this direction was more often voted down in groups of non-cooperative types. We discuss the relevance of the hard problem and fit our results into a bigger picture of institutional and individual determinants of cooperative behavior.

  8. Systematic hardness studies on lithium niobate crystals

    K G Subhadra; K Kishan Rao; D B Sirdeshmukh


    In view of discrepancies in the available information on the hardness of lithium niobate, a systematic study of the hardness has been carried out. Measurements have been made on two pure lithium niobate crystals with different growth origins, and a Fe-doped sample. The problem of load variation of hardness is examined in detail. The true hardness of LiNbO3 is found to be 630 ± 30 kg/mm2. The Fe-doped crystal has a larger hardness of 750 ± 50 kg/mm2.

  9. Autonomous driving in NMR.

    Perez, Manuel


    The automatic analysis of NMR data has been a much-desired endeavour for the last six decades, as it is the case with any other analytical technique. This need for automation has only grown as advances in hardware; pulse sequences and automation have opened new research areas to NMR and increased the throughput of data. Full automatic analysis is a worthy, albeit hard, challenge, but in a world of artificial intelligence, instant communication and big data, it seems that this particular fight is happening with only one technique at a time (let this be NMR, MS, IR, UV or any other), when the reality of most laboratories is that there are several types of analytical instrumentation present. Data aggregation, verification and elucidation by using complementary techniques (e.g. MS and NMR) is a desirable outcome to pursue, although a time-consuming one if performed manually; hence, the use of automation to perform the heavy lifting for users is required to make the approach attractive for scientists. Many of the decisions and workflows that could be implemented under automation will depend on the two-way communication with databases that understand analytical data, because it is desirable not only to query these databases but also to grow them in as much of an automatic manner as possible. How these databases are designed, set up and the data inside classified will determine what workflows can be implemented. Copyright © 2016 John Wiley & Sons, Ltd.

  10. Hard Identity and Soft Identity

    Hassan Rachik


    Full Text Available Often collective identities are classified depending on their contents and rarely depending on their forms. Differentiation between soft identity and hard identity is applied to diverse collective identities: religious, political, national, tribal ones, etc. This classification is made following the principal dimensions of collective identities: type of classification (univocal and exclusive or relative and contextual, the absence or presence of conflictsof loyalty, selective or totalitarian, objective or subjective conception, among others. The different characteristics analysed contribute to outlining an increasingly frequent type of identity: the authoritarian identity.

  11. Sampling hard to reach populations.

    Faugier, J; Sargeant, M


    Studies on 'hidden populations', such as homeless people, prostitutes and drug addicts, raise a number of specific methodological questions usually absent from research involving known populations and less sensitive subjects. This paper examines the advantages and limitations of nonrandom methods of data collection such as snowball sampling. It reviews the currently available literature on sampling hard to reach populations and highlights the dearth of material currently available on this subject. The paper also assesses the potential for using these methods in nursing research. The sampling methodology used by Faugier (1996) in her study of prostitutes, HIV and drugs is used as a current example within this context.

  12. Thermopile detector radiation hard readout

    Gaalema, Stephen; Van Duyne, Stephen; Gates, James L.; Foote, Marc C.


    The NASA Jupiter Europa Orbiter (JEO) conceptual payload contains a thermal instrument with six different spectral bands ranging from 8μm to 100μm. The thermal instrument is based on multiple linear arrays of thermopile detectors that are intrinsically radiation hard; however, the thermopile CMOS readout needs to be hardened to tolerate the radiation sources of the JEO mission. Black Forest Engineering is developing a thermopile readout to tolerate the JEO mission radiation sources. The thermal instrument and ROIC process/design techniques are described to meet the JEO mission requirements.

  13. Hard Fault Analysis of Trivium

    Yupu, Hu; Yiwei, Zhang


    Fault analysis is a powerful attack to stream ciphers. Up to now, the major idea of fault analysis is to simplify the cipher system by injecting some soft faults. We call it soft fault analysis. As a hardware-oriented stream cipher, Trivium is weak under soft fault analysis. In this paper we consider another type of fault analysis of stream cipher, which is to simplify the cipher system by injecting some hard faults. We call it hard fault analysis. We present the following results about such attack to Trivium. In Case 1 with the probability not smaller than 0.2396, the attacker can obtain 69 bits of 80-bits-key. In Case 2 with the probability not smaller than 0.2291, the attacker can obtain all of 80-bits-key. In Case 3 with the probability not smaller than 0.2291, the attacker can partially solve the key. In Case 4 with non-neglectable probability, the attacker can obtain a simplified cipher, with smaller number of state bits and slower non-linearization procedure. In Case 5 with non-neglectable probability,...

  14. Nanostructural Evolution of Hard Turning Layers in Carburized Steel

    Bedekar, Vikram

    speed indicated thermal transformation. Nanoindentation tests showed that the substructures produced by plastic deformation follow the Hall-Petch relationship while the structures produced by thermal transformation did not. This indicated a change in the hardness driver from dislocation hardening to phase transformation, both of which have a significant impact on fatigue life. Using hardness based flow stress numerical model, these relationships between the processing conditions and structural parameters were further explored. Results indicated that the hard turning process design space can be partitioned into three regions based on thermal phase transformations, plastic grain refinement, and a third regime where both mechanisms are active. It was found that the Zener-Holloman parameter can not only be used to predict post-turning grain size but also to partition the process space into regions of dominant microstructural mechanisms.

  15. Drive-By Pharming

    Stamm, Sid; Ramzan, Zulfikar; Jakobsson, Markus

    This paper describes an attack concept termed Drive-by Pharming where an attacker sets up a web page that, when simply viewed by the victim (on a JavaScript-enabled browser), attempts to change the DNS server settings on the victim's home broadband router. As a result, future DNS queries are resolved by a DNS server of the attacker's choice. The attacker can direct the victim's Internet traffic and point the victim to the attacker's own web sites regardless of what domain the victim thinks he is actually going to, potentially leading to the compromise of the victim's credentials. The same attack methodology can be used to make other changes to the router, like replacing its firmware. Routers could then host malicious web pages or engage in click fraud. Since the attack is mounted through viewing a web page, it does not require the attacker to have any physical proximity to the victim nor does it require the explicit download of traditional malicious software. The attack works under the reasonable assumption that the victim has not changed the default management password on their broadband router.

  16. Ecology of a key ecosystem engineer on hard coastal infrastructure and natural rocky shores.

    Martins, Gustavo M; Neto, Ana I; Cacabelos, Eva


    The numbers of hard coastal artificial structures is increasing worldwide and there is now cumulative evidence that they support assemblages that are less diverse than natural shores. Here we investigated patterns of distribution and demography of the native barnacle Chthamalus stellatus on hard coastal structures and on natural rocky shores. Barnacles were 35% less abundant on hard structures regardless of substratum type (concrete or basalt). On a subset of sites we found that temporal population stability, growth and mortality were similar on natural rocky shores and hard structures. In contrast, barnacles were significantly larger and recruited more onto natural rocky shores. These results emphasise the important role of recruitment in determining the abundance of a key space occupier on hard coastal structures. Experimental work building on these results may generate insights that can be used as guidelines for the management of urbanised coastal areas.

  17. Dark Matter Detection with Hard X-ray Telescopes

    Jeltema, Tesla E


    We analyze the impact of future hard X-ray observations on the search for indirect signatures of particle dark matter in large extragalactic systems such as nearby clusters or groups of galaxies. We argue that the hard X-ray energy band falls squarely at the peak of the inverse Compton emission from electrons and positrons produced by dark matter annihilation or decay for a large class of dark matter models. Specifically, the most promising are low-mass models with a hard electron-positron annihilation final state spectrum and intermediate-mass models with a soft electron-positron spectrum. We find that constraints on dark matter models similar to the current constraints from the Fermi Gamma-Ray Space Telescope will be close to the limit of the sensitivity of the near-term hard X-ray telescopes NuSTAR and ASTRO-H for relatively long observations, but an instrument similar to the Wide Field Imager proposed for the International X-ray Observatory would allow significant gains to be made. In the future, the abil...

  18. Increasing Following Headway with Prompts, Goal Setting, and Feedback in a Driving Simulator

    Arnold, Michelle L.; Van Houten, Ron


    We evaluated the effects of prompting, goal setting, and feedback on following headway of young drivers in a simulated driving environment and assessed whether changes produced in following headway were associated with reductions in hard braking when drivers were and were not using cell phones. Participants were 4 university students. During…

  19. Low Sex Drive in Women

    Diseases and Conditions Low sex drive in women By Mayo Clinic Staff A woman's sexual desire naturally fluctuates over the years. Highs and lows commonly ... and anti-seizure medications also can cause low sex drive in women. If you have a persistent ...

  20. Driving Resistance from Railroad Trains

    Lindgreen, Erik Bjørn Grønning; Sorenson, Spencer C


    This report methods and parameters for calculating the driving resistance of railroad trains. Calculations and comparisons are presented for aerodynamic, rolling and total resistance for a variety of freight trains under different loading conditions, operating speed and configuration. Simplified...... methods are presented for the estimation of the driving resistance for passenger trains. This report is a supplement to the ARTEMIS rail emissions model....

  1. Real-world driving behaviour

    Rijkeboer, R.C.; Hendriksen, P.; Gense, N.L.J.


    With increasing complexity of engine management system there is a tendency for traditional driving cyles to become further and further removed from reality. So for a sensible evaluation of emissions and fuel consumption of road vehicles in the field there is an urgent need for 'real-world' driving p

  2. Non-inductive current drive

    Westerhof, E.


    This lecture addresses the various ways of non-inductive current generation. In particular, the topics covered include the bootstrap current, RF current drive, neutral beam current drive, alternative methods, and possible synergies between different ways of non-inductive current generation.


    Westerhof, E.


    This lecture addresses the various ways of non-inductive current generation. In particular, the topics covered include the bootstrap current, RF current drive, neutral beam current drive, alternative methods, and possible synergies between different ways of non-inductive current generation.

  4. Motor Integrated Variable Speed Drives

    Singh, Yash Veer

    A new trend in the variable speed drives (VSDs) is to develop fully integrated systems, which lead to low-cost products with shorter design cycles. Motor Integrated design of VSDs will reduce cable length to connect drive with machine windings and installation time for end user. The electric drives...... are expected to have minimum effect on grid and motor connected to it, i.e. currents drawn from grid should be within specified limits and currents injecting in to machine should not overheat the machine windings to avoid insulation failure due to harmonics. It is also necessary that electric drives should...... when it comes to the development of any kind of power converter topology for power electronic applications. Concerning the use of a power converter in motor integrated VSDs, the first two mentioned aspects receive an even greater im-portance. Power converter design for integrated drives poses a host...

  5. Disarming the Trolley Problem –Why Self-driving Cars do not Need to Choose Whom to Kill

    Johansson, Rolf; Nilsson, Jonas


    International audience; Many claim that the “Trolley problem” is hindering the introduction of self-driving cars. Self-driving cars must, as all safety-critical products, be designed such that the probability of morally hard (“trolley”) situations is acceptably low. In this paper we argue that the introduction of self-driving cars can solve this ethical dilemma. In short the solution to the trolley problem is that a self-driving car must be able to estimate its own operational capability for ...

  6. Hard Times as Bodie: the allegorical functionality in E.L. Doctorow’s Welcome to Hard Times (1960

    P. van der Merwe


    Full Text Available “Welcome to Hard Times” (1960, E.L. Doctorow’s first novel, differs from the rest of his oeuvre because it is not set in a metropolitan context like New York. References to historical events that contain an apparent “mixture” of “factual” and fictional elements that are typical of Doctorow’s oeuvre are less prominent than in his other fiction, though definitely not absent. An analysis of the pioneer setting, the town Hard Times, reveals that other settings (including metropolitan ones like New York are not merely representations of specific contexts, but portrayals with allegorical elements. Criticism of Doctorow’s fiction does not sufficiently point out the rationale of Doctorow’s fiction in relation to his first novel: it is not just the basic level that contains the true topicality but also the underlying causal and thematic relationships. This article sets out to explore “Welcome to Hard Times” as a case in point. The objective of this article is therefore also to show that an analysis of this novel provides a valuable basis for understanding the allegorical character of his fiction. Angus Fletcher’s theoretical analysis, “Allegory: the theory of a symbolic mode” (1964, serves as a useful starting point for the analysis of the allegorical value of space and the town Hard Times as a microcosmic or symbolic society, as well as the “daemonic agents” in the town and the role of causality.

  7. Friction self-oscillation decrease in nonlinear system of locomotive traction drive

    Antipin, D. Ya; Vorobiyov, V. I.; Izmerov, O. V.; Shorokhov, S. G.; Bondarenko, D. A.


    The problems of the friction self-oscillation decrease in a nonlinear system of a locomotive traction drive are considered. It is determined that the self-oscillation amplitude decrease in a locomotive wheel pair during boxing in traction drives with an elastic linkage between an armature of a traction electric motor and gearing can be achieved due to drive damping capacity during impact vibro-damping in an axle reduction gear with a hard driven gear. The self-oscillation amplitude reduction in a wheel pair in the designs of locomotive traction drives with the location of elastic elements between a wheel pair and gearing can be obtained owing to the application of drive inertial masses as an anti-vibrator. On the basis of the carried out investigations, a design variant of a self-oscillation shock absorber of a traction electric motor framework on a reduction gear suspension with an absorber located beyond a wheel-motor unit was offered.

  8. Hard rock, heavy metal, metal

    Hein, Fabien


    Le terme générique metal désigne une multitude de genres et de sous-genres musicaux issus de l’appariement du hard rock et du heavy metal. Il résulte d’une agrégation sémantique consécutive de l’érosion et de l’interpénétration de ces termes au cours des années 1980. Leurs modèles canoniques, respectivement représentés par les groupes Led Zeppelin et Black Sabbath, se sont progressivement dilués sous l’effet d’une filiation particulièrement effervescente et féconde : black, thrash, doom, prog...

  9. Probing Strangeness in Hard Processes

    Avakian, H; Cisbani, E; Contalbrigo, M; D'Alesio, U; De Leo, R; Devita, R; Di Nezza, P; Hasch, D; Mirazita, M; Osipenko, M; Pappalardo, L; Rossi, P


    Since the discovery of strangeness almost five decades ago, interest in this degree of freedom has grown up and now its investigation spans the scales from quarks to nuclei. Measurements with identified strange hadrons can provide important information on several hot topics in hadronic physics: the strange distribution and fragmentation functions, the nucleon tomography and quark orbital momentum, accessible through the study of the {\\it generalized} parton distribution and the {\\it transverse momentum dependent} parton distribution functions, the quark hadronization in the nuclear medium, the hadron spectroscopy and the search for exotic mesons. The CLAS12 large acceptance spectrometer in Hall B at the Jefferson Laboratory upgraded with a RICH detector together with the 12 GeV CEBAF high intensity, high polarized electron beam can open new possibilities to study strangeness in hard processes allowing breakthroughs in all those areas. This paper summarizes the physics case for a RICH detector for CLAS12. Many...

  10. A hard case for modeling

    George Marsh


    Some fighter pilots alive today owe their survival to tough, low-weight helmets whose qualities have been refined as a result of biomechanical modeling. Porter and his colleagues have modeled the human head as a mechanical arrangement of a heavy ball on a rod support, as a system of soft matter contained in a hard case, as an arrangement of meso-scale sub-systems, and as a combination of material systems built up from the nano-molecular and atomic scales. An extensive modeling hierarchy (Fig. 1 is held on nothing more esoteric than a networked workstation and server architecture. Nevertheless, thanks to a process of focused simplification at each hierarchical level, it is able to predict the mechanical behavior of the human head and its constituents in reacting to impacts with considerable accuracy.

  11. Schwannoma of the hard palate.

    Isildak, Huseyin; Yilmaz, Mehmet; Ibrahimov, Metin; Aslan, Mehmet; Karaman, Emin; Enver, Ozgun


    About half of all neurogenic tumors are seen in the head and neck region. The types of neurogenic tumors must be distinguished. Schwannomas originate from Schwann cells of the neural sheath and are solitary, well-encapsulated, slow-growing adjacent to the parental nerve but extrinsic to the nerve fascicles.Approximately 25% to 45% of all schwannomas are seen in the head and neck region and are found rarely in the oral cavity. Most of the intraoral schwannomas are located in the tongue. Other less common locations are the buccal mucosa, palate, base of the mouth, gingiva, and lips.In this study, we report a rare case of schwannoma of the hard palate, which was excised intraorally.

  12. Hydraulic Motor Driving Variable-Pitch System for Wind Turbine

    Ye HUANG


    Full Text Available The present hydraulic variable-pitch mechanism of wind turbine uses three hydraulic cylinders to drive three crank and connecting rod mechanisms respectively; the blades are moved with the cranks. The hydraulic variable-pitch mechanism has complex structure, occupies a lot of space and its maintenance is trouble. In order to make up for the shortcomings of hydraulic cylinder variable-pitch system, the present hydraulic variable-pitch mechanism should be changed as follows: hydraulic motors are used to drive gears; gears drive blades; the electro-hydraulic proportional valves are used to control hydraulic motors. The hydraulic control part and electrical control part of variable-pitch system is redesigned. The new variable-pitch system is called hydraulic motor driving variable-pitch system. The new variable-pitch system meets the control requirements of blade pitch, makes the structure simple and its application effect is perfect.    

  13. Friction drive of an SAW motor. Part II: analyses.

    Shigematsu, Takashi; Kurosawa, Minoru Kuribayashi


    The mechanics of the friction drive of a surface acoustic wave motor were investigated by means of contact mechanics theory. As a means to control the contact condition, the motor's slider had projections on its frictional surface. Assuming the projection was a rigid circular punch and the slider body was an elastic half-space allowed application of contact mechanics formulae to the analyses of the friction drive. Because the projection contacted the Rayleigh wave vibration, the projection's responses were considered dynamic; thus, the dynamics were also analyzed in the same framework of contact mechanics formulae. Moreover, the analyses were applied to measurements of the projection's displacement to examine the detailed mechanics during the friction drive. We calculated the contact/frictional forces based on the measurement and indicated the necessity of further investigation of the surface acoustic wave motor's friction drive, because the usual friction law was unable to explain the measurement.

  14. Phase-matched generation of coherent soft and hard X-rays using IR lasers

    Popmintchev, Tenio V.; Chen, Ming-Chang; Bahabad, Alon; Murnane, Margaret M.; Kapteyn, Henry C.


    Phase-matched high-order harmonic generation of soft and hard X-rays is accomplished using infrared driving lasers in a high-pressure non-linear medium. The pressure of the non-linear medium is increased to multi-atmospheres and a mid-IR (or higher) laser device provides the driving pulse. Based on this scaling, also a general method for global optimization of the flux of phase-matched high-order harmonic generation at a desired wavelength is designed.

  15. Hard X-ray Timing with EXIST

    Grindlay, J E


    The Energetic X-ray Timing Survey Telescope (EXIST) mission concept is under study as the Black Hole Finder Probe (BHFP), one of the three Einstein Probe missions in the Beyond Einstein Program in the current NASA Strategic Plan. EXIST would conduct an all-sky imaging hard X-ray ($\\sim$10-600 keV) survey with unprecedented sensitivity: about 5 $\\times 10^{-13}$ cgs over any factor of 2 bandwidth, or comparable to that achieved at soft X-rays in the ROSAT survey. The proposed angular resolution of 5arcmin, temporal resolution of 10microsec, energy resolution of 1-4 keV over the broad band, and duty cycle of 0.2-0.5 for continuous coverage of any source provide an unprecedented phase space for timing and spectral studies of black holes --from stellar to supermassive, as well as neutron stars and accreting white dwarfs. The large sky coverage allows intrinsically rare events to be studied. One particularly exciting example is the possible detection of tidal disruption of stars near quiescent AGN. Super flares fr...

  16. Uncooled Radiation Hard Large Area SiC X-ray and EUV Detectors and 2D Arrays Project

    National Aeronautics and Space Administration — This project seeks to design, fabricate, characterize and commercialize large area, uncooled and radiative hard 4H-SiC EUV ? soft X-ray detectors capable of ultra...

  17. Hardware Assisted ROP Detection Mode (HARD Mode)


    Distribution A. Cleared for public release; unlimited distribution. USAFA-CN-2013-457 Hardware Assisted ROP Detection Mode (HARD Mode) NATHANIEL HART...457 This report, "Hardware Assisted ROP Detection Mode (HARD Mode)" is presented as a competent treatment of the subj ect, worthy of publication. The...Technical 20120810-20121215 Hardware Assisted ROP Detection Mode (HARD Mode) NATHANIEL HART MICHAEL WINSTEAD MARTIN CARLISLE RODNEY LYKINS MICHAEL

  18. Shock Waves in Dense Hard Disk Fluids

    Sirmas, Nick; Tudorache, Marion; Barahona, Javier; Radulescu, Matei I.


    Media composed of colliding hard disks (2D) or hard spheres (3D) serve as good approximations for the collective hydrodynamic description of gases, liquids and granular media. In the present study, the compressible hydrodynamics and shock dynamics are studied for a two-dimensional hard-disk medium at both the continuum and discrete particle level descriptions. For the continuum description, closed form analytical expressions for the inviscid hydrodynamic description, shock Hugoniot, isentropi...

  19. Operators associated with soft and hard spectral edges from unitary ensembles.

    Blower, Gordon


    Using Hankel operators and shift-invariant subspaces on Hilbert space, this paper develops the theory of integrable operators associated with soft and hard edges of eigenvalues distributions of random matrices. Such Tracy--Widom operators are realized as controllability operators for linear systems, and are reporducing kernels for weighted Hardy spaces, known as Sonine spaces. Periodic solutions of Hill's equation give a new family of Tracy--Widom type operators. This paper identifies a pair ...

  20. Reformatting the hard drive of South African education for the knowledge economy


    South African education system needs reformatting in order to produce employable graduates. By introducing educational gaming into the formal learning programmes, the nature and quality of learning can be enhanced to create the innovative professionals need for the new knowledge economy.

  1. Micromagnetic simulation of FeCo write head in perpendicular recording hard disk drives

    QUAN Liang; WEI Dan


    The single-pole tip (SPT) heads made of the high saturation FeCo ferromagnetic metals are crucial for the actualization of ultrahigh density perpendicular recording. The effective head field distribution in the medium is of key importance for the design of the SPT head, which would be analyzed by micromagnetic simulations in this work. Two 3D micromagnetic models of the SPT head were established to select a more appropriate method of modeling, with a magnetostatic image effect or a real soft magnetic material to model the image of the SPT head in soft under layer (SUL). The results from these two designs were tested and compared to the ideal head field calculated by the Jacobi finite element method (FEM); and the design with the real soft magnetic material as image was proved suitable for simulating the ultrahigh density perpendicular recording write head.

  2. Reformatting the hard drive of South African education for the knowledge economy

    Jason Davis


    Full Text Available South African education system needs reformatting in order to produce employable graduates. By introducing educational gaming into the formal learning programmes, the nature and quality of learning can be enhanced to create the innovative professionals need for the new knowledge economy.

  3. From Compass to Hard Drive--Integrated Activities for Studying Magnets

    Dean, J.; Allwood, D. A.


    We describe a range of practical activities that allows students to investigate the properties and applications of magnets. The activities can be used in isolation or used together to build a rounded understanding of the subject area. The activities include simple demonstrations using common or inexpensive equipment, hands-on experiments for small…

  4. Flexible drive allows blind machining and welding in hard-to-reach areas

    Harvey, D. E.; Rohrberg, R. G.


    Flexible power and control unit performs welding and machining operations in confined areas. A machine/weld head is connected to the unit by a flexible transmission shaft, and a locking- indexing collar is incorporated onto the head to allow it to be placed and held in position.

  5. Hard sphere dynamics for normal and granular fluids.

    Dufty, James W; Baskaran, Aparna


    A fluid of N smooth, hard spheres is considered as a model for normal (elastic collision) and granular (inelastic collision) fluids. The potential energy is discontinuous for hard spheres so that the pairwise forces are singular and the usual forms of Newtonian and Hamiltonian mechanics do not apply. Nevertheless, particle trajectories in the N particle phase space are well defined and the generators for these trajectories can be identified. The first part of this presentation is a review of the generators for the dynamics of observables and probability densities. The new results presented in the second part refer to applications of these generators to the Liouville dynamics for granular fluids. A set of eigenvalues and eigenfunctions of the generator for this Liouville dynamics system is identified in a special stationary representation. This provides a class of exact solutions to the Liouville equation that are closely related to hydrodynamics for granular fluids.

  6. Automated driving safer and more efficient future driving

    Horn, Martin


    The main topics of this book include advanced control, cognitive data processing, high performance computing, functional safety, and comprehensive validation. These topics are seen as technological bricks to drive forward automated driving. The current state of the art of automated vehicle research, development and innovation is given. The book also addresses industry-driven roadmaps for major new technology advances as well as collaborative European initiatives supporting the evolvement of automated driving. Various examples highlight the state of development of automated driving as well as the way forward. The book will be of interest to academics and researchers within engineering, graduate students, automotive engineers at OEMs and suppliers, ICT and software engineers, managers, and other decision-makers.

  7. Potential health impacts of hard water

    Sengupta, Pallav


    ... the hardness of the drinking water. In addition, several epidemiological investigations have demonstrated the relation between risk for cardiovascular disease, growth retardation, reproductive failure, and other health problems...

  8. The Driving Pipeline: A Driving Control Scheme for Mobile Robots


    ATrvnCrlShemefortMobilesRobots K)BODTIC MTT Tehnca Report The Driving Pipeline: A Driving Control Scheme for Mobile Robots Yoshimasa Goto, Steven A...October, 1986. [4] Georges Giralt, Raja Chatila, and Marc Vaisset. An Integrated Navigation and Motion Control System for Autonomous Multsensory Mobile ... Robots . In The First International Symposium on Robotics Research, pages 191-214. j5] Y.Goto, etc.. C1M Sidewalk Navigation System. In Proc. of Fall


    Sanaz Motamedi; Jyh-Hone Wang


    In an increasingly mobile era, the wide availability of technology for texting and the prevalence of hands-free form have introduced a new safety concern for drivers. To assess this concern, a questionnaire was first deployed online to gain an understanding of drivers’ text driving experiences as well as their demographic information. The results from 232 people revealed that the majority of drivers are aware of the associated risks with texting while driving. However, more than one-fourth of...

  10. eHXI: a permanently installed, hard x-ray imager for the National Ignition Facility

    Döppner, T.; Bachmann, B.; Albert, F.; Bell, P.; Burns, S.; Celeste, J.; Chow, R.; Divol, L.; Dewald, E. L.; Hohenberger, M.; Huntington, C. M.; Izumi, N.; LaCaille, G.; Landen, O. L.; Palmer, N.; Park, H.-S.; Thomas, C. A.


    We have designed and built a multi-pinhole imaging system for high energy x-rays (>= 50 keV) that is permanently installed in the equatorial plane outside of the target chamber at the National Ignition Facility (NIF). It records absolutely-calibrated, time-integrated x-ray images with the same line-of-sight as the multi-channel, spatially integrating hard x-ray detector FFLEX [McDonald et al., Rev. Sci. Instrum. 75 (2004) 3753], having a side view of indirect-drive inertial confinement fusion (ICF) implosion targets. The equatorial hard x-ray imager (eHXI) has recorded images on the majority of ICF implosion experiments since May 2011. eHXI provides valuable information on hot electron distribution in hohlraum experiments, target alignment, potential hohlraum drive asymmetries and serves as a long term reference for the FFLEX diagnostics.

  11. Time-resolved scanning Kerr microscopy of flux beam formation in hard disk write heads

    Valkass, Robert A. J.; Spicer, Timothy M.; Burgos Parra, Erick; Hicken, Robert J.; Bashir, Muhammad A.; Gubbins, Mark A.; Czoschke, Peter J.; Lopusnik, Radek


    To meet growing data storage needs, the density of data stored on hard disk drives must increase. In pursuit of this aim, the magnetodynamics of the hard disk write head must be characterized and understood, particularly the process of "flux beaming." In this study, seven different configurations of perpendicular magnetic recording (PMR) write heads were imaged using time-resolved scanning Kerr microscopy, revealing their detailed dynamic magnetic state during the write process. It was found that the precise position and number of driving coils can significantly alter the formation of flux beams during the write process. These results are applicable to the design and understanding of current PMR and next-generation heat-assisted magnetic recording devices, as well as being relevant to other magnetic devices.

  12. Control Schemes for Driving Electro-optic Array Beam Deflectors


    The beam deflectors based on electro-optic phased array(EOPA) is mainly described, and then an analysis on existing control schemes for driving the EOPA beam deflectors, based on custom hard-wired electronics or based on software in a microcontroller, is made. Compared with these, a driving and control system for a multi-channel EOPA beam deflector is presented, in which the control assignment is implemented with a field programmable gate array(FPGA) chip. For different performance requirements, two control schemes, one with the serial scheme and another with the parallel scheme, have been explored and rapidly prototyped in Xilinx FPGA chips. With the control structures for the EOPA beam deflector, scanning rates of 588kHz and 5MHz can be respectively reached.

  13. Testing of a direct drive generator for wind turbines

    Sondergaard, L.M. [Riso National Laboratory, Roskilde (Denmark)


    The normal drive train of a wind turbine consists a gearbox and a 4 to 8 poles asynchronous generator. The gearbox is an expensive and unreliable components and this paper deals with testing of a direct drive synchronous generator for a gearless wind turbine. The Danish company Belt Electric has constructed and manufactured a 27 kW prototype radial flux PM-generator (DD600). They have used cheap hard ferrite magnets in the rotor of this PM-generator. This generator has been tested at Riso and the test results are investigated and analyzed in this paper. The tests have been done with three different load types (1: resistance; 2: diode rectifier, DC-capacitor, resistance; 3: AC-capacitor, diode rectifier, DC-capacitor, resistance). 1 ref., 9 figs., 5 tabs.

  14. PASS:a simple, efficient parallelism-aware solid state drive I/O scheduler

    Hong-yan LI; Nai-xue XIONG; Ping HUANG; Chao GUI


    Emerging non-volatile memory technologies, especially flash-based solid state drives (SSDs), have increasingly been adopted in the storage stack. They provide numerous advantages over traditional mechanically rotating hard disk drives (HDDs) and have a tendency to replace HDDs. Due to the long existence of HDDs as primary building blocks for storage systems, however, much of the system software has been specially designed for HDD and may not be optimal for non-volatile memory media. Therefore, in order to realistically leverage its superior raw performance to the maximum, the existing upper layer software has to be re-evaluated or re-designed. To this end, in this paper, we propose PASS, an optimized I/O scheduler at the Linux block layer to accommodate the changing trend of underlying storage devices toward flash-based SSDs. PASS takes the rich internal parallelism in SSDs into account when dispatching requests to the device driver in order to achieve high performance. Specifically, it parti-tions the logical storage space into fixed-size regions (preferably the component package sizes) as scheduling units. These scheduling units are serviced in a round-robin manner and for every chance that the chosen dispatching unit issues only a batch of either read or write requests to suppress the excessive mutual interference. Additionally, the requests are sorted according to their visiting addresses while waiting in the dispatching queues to exploit high sequential performance of SSD. The experimental results with a variety of workloads have shown that PASS outperforms the four Linux off-the-shelf I/O schedulers by a degree of 3%up to 41%, while at the same time it improves the lifetime significantly, due to reducing the internal write amplification.

  15. Development and validation of a mechatronic solar array drive assembly for mini/micro-satellites

    Li, Rui; Guo, Feng; Yu, Chunxu; He, Yu; Ye, Zhuang; Yuan, Shuai


    Starting from the 1990s, the mini/micro-satellites around 50-200 kg become one of the research focuses of space industry. Different from the mini-satellites developed at early ages, modern mini/micro-satellites widely incorporate micro-electronics and micro-mechanisms, emphasizing multi-functionality and system integration. As a result, they have relatively high power/volume ratio. Also, to reduce the fuel consumption, the application of micro-electrical propulsion systems on mini/micro-satellites is increasing, which pushes the requirement for electrical power even higher. It is hard for the surface mounted solar cells and stationary solar arrays which were widely used by micro-satellites at early ages to satisfy these elevating power requirements of modern mini/micro-satellites. In response to these requirements, Solar Array Drive Assemblies (SADA) which used to be standard equipments of large spacecrafts have gradually been incorporated in the mini/micro-satellites to rotate the solar arrays for maximum sunlight acquisition, and tremendously reduce the size and mass of the solar arrays.

  16. Is Drunk Driving a Felony?


    Drunk driving, a major killer in China for decades, may soon incur harsher penalties for offenders. Several high-profile alcoholrelated traffic accidents in recent months have triggered a nationwide debate on

  17. Quantum effects in warp drives

    Finazzi Stefano


    Full Text Available Warp drives are interesting configurations that, at least theoretically, provide a way to travel at superluminal speed. Unfortunately, several issues seem to forbid their realization. First, a huge amount of exotic matter is required to build them. Second, the presence of quantum fields propagating in superluminal warp-drive geometries makes them semiclassically unstable. Indeed, a Hawking-like high-temperature flux of particles is generated inside the warp-drive bubble, which causes an exponential growth of the energy density measured at the front wall of the bubble by freely falling observers. Moreover, superluminal warp drives remain unstable even if the Lorentz symmetry is broken by the introduction of regulating higher order terms in the Lagrangian of the quantum field. If the dispersion relation of the quantum field is subluminal, a black-hole laser phenomenon yields an exponential amplification of the emitted flux. If it is superluminal, infrared effects cause a linear growth of this flux.

  18. Alzheimer's: When to Stop Driving

    Healthy Lifestyle Caregivers If your loved one has Alzheimer's, he or she may not be safe on ... for safe driving tends to decline with age, Alzheimer's disease accelerates this process dramatically. If you're ...

  19. Clinical Action against Drunk Driving.

    Donald A Redelmeier


    Full Text Available In advance of a safety campaign on 17 March 2017, Donald Redelmeier and Allan Detsky call on physicians and clinical colleagues to reduce the chances that patients will drive drunk.

  20. Study of the Radiation-Hardness of VCSEL and PIN

    Gan, K K; Fernando, W; Kagan, H P; Kass, R D; Lebbai, M R M; Merritt, H; Moore, J R; Nagarkar, A; Rizatdinova, F; Skubic, P L; Smith, D S; Strang, M


    The silicon trackers of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN (Geneva) use optical links for data transmission. An upgrade of the trackers is planned for the Super LHC (SLHC), an upgraded LHC with ten times higher luminosity. We study the radiation-hardness of VCSELs (Vertical-Cavity Surface-Emitting Laser) and GaAs and silicon PINs using 24 GeV/c protons at CERN for possible application in the data transmission upgrade. The optical power of VCSEL arrays decreases significantly after the irradiation but can be partially annealed with high drive currents. The responsivities of the PIN diodes also decrease significantly after irradiation, but can be recovered by operating at higher bias voltage. This provides a simple mechanism to recover from the radiation damage.

  1. Radiation-hard/high-speed array-based optical engine

    Gan, K. K.; Buchholz, P.; Heidbrink, S.; Kagan, H. P.; Kass, R. D.; Moore, J.; Smith, D. S.; Vogt, M.; Ziolkowski, M.


    We have designed and fabricated a compact array-based optical engine for transmitting data at 10 Gb/s. The device consists of a 4-channel ASIC driving a VCSEL (Vertical Cavity Surface Emitting Laser) array in an optical package. The ASIC is designed using only core transistors in a 65 nm CMOS process to enhance the radiation-hardness. The ASIC contains an 8-bit DAC to control the bias and modulation currents of the individual channels in the VCSEL array. The DAC settings are stored in SEU (single event upset) tolerant registers. Several devices were irradiated with 24 GeV/c protons and the performance of the devices is satisfactory after the irradiation.

  2. Mulholland Drive: An Intertextual Reading

    Ebrahim Barzegar


    Full Text Available This article examines David Lynch’s Mulholland Drive from Kristeva’s concept of intertextuality. To achieve this aim, this study provides a close reading of the selected film so as to trace and illustrate the polyphonic network of references, citations, quotations and intertexts of Mulholland Drive to the significant already-made films such as Sunset Boulevard, The Wizard of Oz, and Persona.


    LI Xianghua; ZHANG Jianwu


    A newly found phenomenon of carved driving wheels of a rea-wheel-drive tractor used in an airport is discussed. The circum of every driving wheel is damaged at three regions, which distribute regularly and uniformly. Everyday, the tractor tows a trailer which are times heavier than the tractor, and moves on the same road in the airport. The phenomenon is explained by the torsional self-excited vibration system of the powertrain. The simplified torsional vibration system is discribed by a 2-order ordinary differential equation, which has a limit circle. Experiments and numerical simulations show the followings: Because of the heavy trailer, the slip ratio of the tractor's driving wheels is very large. Therefore, there is severe torsional self-excited vibration in the tractor's drivetrain, and the self-excited vibration results in severe and regular fluctuations of the rear wheel's velocity. The severe fluctuations in velocity fastens the damage of the driving wheels. At the same time, the time interval in which an arbitrary point in the circum of the driving wheel contacts with the road twice is two times more than the period of the torsional self-excited vibration, and this times explained the existence of three damaged regions. At last, it points out that the phenomenon can be avoided when the torsional damping is large enough.

  4. Low backlash direct drive actuator

    Kuklo, Thomas C.


    A low backlash direct drive actuator is described which comprises a motor such as a stepper motor having at least 200 steps per revolution; a two part hub assembly comprising a drive hub coaxially attached to the shaft of the motor and having a plurality of drive pins; a driven hub having a plurality of bores in one end thereof in alignment with the drive pins in the drive hub and a threaded shaft coaxially mounted in an opposite end of the driven hub; and a housing having a central bore therein into which are fitted the drive hub and driven hub, the housing having a motor mount on one end thereof to which is mounted the stepper motor, and a closed end portion with a threaded opening therein coaxial with the central bore in the housing and receiving therein the threaded shaft attached to the driven hub. Limit switches mounted to the housing cooperate with an enlarged lip on the driven hub to limit the lateral travel of the driven hub in the housing, which also acts to limit the lateral travel of the threaded shaft which functions as a lead screw.

  5. Hard disks with SCSI interface

    Denisov, O Yu


    The testing of 20 models of hard SCSI-disks is carried out: the Fujitsu MAE3091LP; the IBM DDRS-39130, DGHS-318220, DNES-318350, DRHS-36V and DRVS-18V; the Quantum Atlas VI 18.2; the Viking 11 9.1; the Seagate ST118202LW, ST118273LW, ST118273W, ST318203LW, ST318275LW, ST34520W, ST39140LW and ST39173W; and the Western Digital WDE9100-0007, WDE9100-AV0016, WDE9100-AV0030 and WDE9180-0048. All tests ran under the Windows NT 4.0 workstation operating system with Service Pack 4, under video mode with 1024*768 pixel resolution, 32- bit colour depth and V-frequency equal to 85 Hz. The detailed description and characteristics of SCSI stores are presented. Test results (ZD Winstone 99 and ZD WinBench 99 tests) are given in both table and diagram (disk transfer rate) forms. (0 refs).

  6. ERRATUM: Work smart, wear your hard hat


    An error appeared in the article «Work smart, wear your hard hat» published in Weekly Bulletin 27/2003, page 5. The impact which pierced a hole in the hard hat worn by Gerd Fetchenhauer was the equivalent of a box weighing 5 kg and not 50 kg.

  7. Retraction of Hard, Lozano, and Tversky (2006)

    Hard, B. M.; Lozano, S. C.; Tversky, B.


    Reports a retraction of "Hierarchical encoding of behavior: Translating perception into action" by Bridgette Martin Hard, Sandra C. Lozano and Barbara Tversky (Journal of Experimental Psychology: General, 2006[Nov], Vol 135[4], 588-608). All authors retract this article. Co-author Tversky and co-author Hard believe that the research results cannot…

  8. Hard Spring Wheat Technical Committee 2016 Crop

    Seven experimental lines of hard spring wheat were grown at up to five locations in 2016 and evaluated for kernel, milling, and bread baking quality against the check variety Glenn. Wheat samples were submitted through the Wheat Quality Council and processed and milled at the USDA-ARS Hard Red Spri...

  9. Numerical Solution of Hard-Core Mixtures

    Buhot, Arnaud; Krauth, Werner


    We study the equilibrium phase diagram of binary mixtures of hard spheres as well as of parallel hard cubes. A superior cluster algorithm allows us to establish and to access the demixed phase for both systems and to investigate the subtle interplay between short-range depletion and long-range demixing.

  10. Study of fast electrons from hard-X radiation; Etude des electrons rapides a partir du rayonnement X-dur

    Arslanbekov, R.


    The goal of this thesis is the study of fast electron dynamics by means of the hard X-ray diagnosis installed in TORE SUPRA and numerical simulations. Fast electrons are generated in the plasma in the presence of the injected lower hybrid (LH) waves. Two aspects are studied in detail: the lower hybrid wave propagation and absorption in a periodically perturbed media and 2-D Fokker-Planck modelling of the fast electron dynamics in the presence of the LH power. Ripple effects on lower hybrid wave propagation and absorption are investigated using the ray tracing technique. A cylindrical equilibrium is first studied and a strong modification of the ray dynamics is predicted. Calculations are carried out in a real toroidal geometry corresponding to TORE SUPRA. It is shown that the lack of toroidal axisymmetry of the magnetic field may result in a modification of the ray evolution even if the global ray evolution is governed by the larger poloidal inhomogeneity. Simulation of LH experiments are performed for TORE SUPRA tokamak which has a large magnetic ripple (7% at the plasma edge). By considering ripple perturbation in LH current drive simulations, a better agreement is found with experimental results, in particular with the hard-X spectra and the current density profiles. In the second part of the thesis, a 2-D modeling of the fast electron dynamics in the velocity phase space is considered, based on the 2-D relativistic electron Fokker-Planck equation. Electron distribution functions obtained are used to calculate non-thermal Bremsstrahlung emission for different TORE SUPRA shots in a wide range of experimental conditions. (J.S.). 168 refs., 93 figs., 1 tab., 3 appendix.

  11. Solar cell nanotechnology for improved efficiency and radiation hardness

    Fedoseyev, Alexander I.; Turowski, Marek; Shao, Qinghui; Balandin, Alexander A.


    Space electronic equipment, and NASA future exploration missions in particular, require improvements in solar cell efficiency and radiation hardness. Novel nano-engineered materials and quantum-dot array based photovoltaic devices promise to deliver more efficient, lightweight solar cells and arrays which will be of high value to long term space missions. In this paper, we describe issues related to the development of the quantum-dot based solar cells and comprehensive software tools for simulation of the nanostructure-based photovoltaic cells. Some experimental results used for the model validation are also reviewed. The novel modeling and simulation tools for the quantum-dot-based nanostructures help to better understand and predict behavior of the nano-devices and novel materials in space environment, assess technologies, devices, and materials for new electronic systems as well as to better evaluate the performance and radiation response of the devices at an early design stage. The overall objective is to investigate and design new photovoltaic structures based on quantum dots (QDs) with improved efficiency and radiation hardness. The inherently radiation tolerant quantum dots of variable sizes maximize absorption of different light wavelengths, i.e., create a "multicolor" cell, which improves photovoltaic efficiency and diminishes the radiation-induced degradation. The QD models described here are being integrated into the advanced photonic-electronic device simulator NanoTCAD, which can be useful for the optimization of QD superlattices as well as for the development and exploring of new solar cell designs.

  12. Hardness methods for testing maize kernels.

    Fox, Glen; Manley, Marena


    Maize is a highly important crop to many countries around the world, through the sale of the maize crop to domestic processors and subsequent production of maize products and also provides a staple food to subsistance farms in undeveloped countries. In many countries, there have been long-term research efforts to develop a suitable hardness method that could assist the maize industry in improving efficiency in processing as well as possibly providing a quality specification for maize growers, which could attract a premium. This paper focuses specifically on hardness and reviews a number of methodologies as well as important biochemical aspects of maize that contribute to maize hardness used internationally. Numerous foods are produced from maize, and hardness has been described as having an impact on food quality. However, the basis of hardness and measurement of hardness are very general and would apply to any use of maize from any country. From the published literature, it would appear that one of the simpler methods used to measure hardness is a grinding step followed by a sieving step, using multiple sieve sizes. This would allow the range in hardness within a sample as well as average particle size and/or coarse/fine ratio to be calculated. Any of these parameters could easily be used as reference values for the development of near-infrared (NIR) spectroscopy calibrations. The development of precise NIR calibrations will provide an excellent tool for breeders, handlers, and processors to deliver specific cultivars in the case of growers and bulk loads in the case of handlers, thereby ensuring the most efficient use of maize by domestic and international processors. This paper also considers previous research describing the biochemical aspects of maize that have been related to maize hardness. Both starch and protein affect hardness, with most research focusing on the storage proteins (zeins). Both the content and composition of the zein fractions affect

  13. Theoretical Hardness of Wurtzite-Structured Semiconductors

    GUO Xiao-Ju; XU Bo; LIU Zhong-Yuan; YU Dong-Li; HE Ju-Long; GUO Li-Cong


    Vickers hardness calculations of eleven wurtzite-structured semiconductors are performed based on the microscopic hardness model All the parameters are obtained from first-principles calculations. There axe two types of chemical bonds in wurtzite-structured crystals. The overlap populations of the two types of chemical bonds in lonsdaleite are chosen as Pc for wurtzite structure. The calculated bond ionicity values of the wurtzite-structured semiconductors are in good agreement with the ionicities from the dielectric definition. When the hardness of wurtzite-structured crystal is higher than 20GPa, our calculated Vickers hardness is within 10% accuracy. Therefore, the hardness of novel wurtzite-structured crystal could be estimated from first-principles calculations.


    Kazi Takpaya


    A wireless floppy disk drive is proposed for home and office wireless local area network. The proposed floppy drive uses turbo coding-decoding in the transceiver PHYsical layer (PHY) to improve system performance. The data transmission rate is about 11 Mbps. The covered distance is 30 meters in obstructed environment and 100 m in free space.

  15. Active damping technique for small DC-link capacitor based drive system

    Maheshwari, Ram Krishan; Munk-Nielsen, Stig; Henriksen, Bjarne


    A detailed model of Adjustable Speed Drive (ASD) is discussed, which yield a general rule for active damping in a small DC link based drive. A desired value of input LC resonance damping coefficient can be achieved by changing gain parameters. The modified state space matrix due to active damping...

  16. Efficient Driving of Piezoelectric Transducers Using a Biaxial Driving Technique.

    Samuel Pichardo

    Full Text Available Efficient driving of piezoelectric materials is desirable when operating transducers for biomedical applications such as high intensity focused ultrasound (HIFU or ultrasound imaging. More efficient operation reduces the electric power required to produce the desired bioeffect or contrast. Our preliminary work [Cole et al. Journal of Physics: Condensed Matter. 2014;26(13:135901.] suggested that driving transducers by applying orthogonal electric fields can significantly reduce the coercivity that opposes ferroelectric switching. We present here the experimental validation of this biaxial driving technique using piezoelectric ceramics typically used in HIFU. A set of narrow-band transducers was fabricated with two sets of electrodes placed in an orthogonal configuration (following the propagation and the lateral mode. The geometry of the ceramic was chosen to have a resonance frequency similar for the propagation and the lateral mode. The average (± s.d. resonance frequency of the samples was 465.1 (± 1.5 kHz. Experiments were conducted in which each pair of electrodes was driven independently and measurements of effective acoustic power were obtained using the radiation force method. The efficiency (acoustic/electric power of the biaxial driving method was compared to the results obtained when driving the ceramic using electrodes placed only in the pole direction. Our results indicate that the biaxial method increases efficiency from 50% to 125% relative to the using a single electric field.

  17. High-power converters and AC drives

    Wu, Bin


    This new edition reflects the recent technological advancements in the MV drive industry, such as advanced multilevel converters and drive configurations. It includes three new chapters, Control of Synchronous Motor Drives, Transformerless MV Drives, and Matrix Converter Fed Drives. In addition, there are extensively revised chapters on Multilevel Voltage Source Inverters and Voltage Source Inverter-Fed Drives. This book includes a systematic analysis on a variety of high-power multilevel converters, illustrates important concepts with simulations and experiments, introduces various megawatt drives produced by world leading drive manufacturers, and addresses practical problems and their mitigations methods.

  18. Assembly of body-centered cubic crystals in hard spheres.

    Xu, W-S; Sun, Z-Y; An, L-J


    We investigate the crystallization of monodisperse hard spheres confined by two square patterned substrates (possessing the basic character of the body-centered cubic (bcc) crystal structure) at varying substrate separations via molecular dynamics simulation. Through slowly increasing the density of the system, we find that crystallization under the influence of square patterned substrates can set in at lower densities compared with the homogeneous crystallization. As the substrate separation decreases, the density, where crystallization occurs (i.e., pressure drops), becomes small. Moreover, two distinct regimes are identified in the plane of bcc particle fraction and density for the separation range investigated. For large substrate separations, the bcc particle fraction displays a local maximum as the density is increased, and the resulting formed crystals have a polycrystalline structure. However, and more importantly, another situation emerges for small substrate separations: the capillary effects (stemming from the presence of two substrates) overwhelm the bulk driving forces (stemming from the spontaneous thermal fluctuations in the bulk) during the densification, eventually resulting in the formation of a defect-free bcc crystal (unstable with respect to the bulk hard-sphere crystals) by using two square patterned substrates.

  19. Radiation Hardness Assurance (RHA): Challenges and New Considerations

    Campola, Michael J.


    Radiation Hardness Assurance (RHA) challenges associated with the use of commercial-off-the-shelf (COTS) components and emerging technologies are cause for risk acceptance in space flight missions. The RHA flow includes environment definition, hazard evaluation, requirements definition, evaluation of design, and design trades to accommodate the risk a project or program takes. The varied missions profiles and environments don't necessarily benefit from the same risk reduction efforts or cost reduction attempts. The level of effort within the RHA flow can be tailored to minimize risk based on the environment or design criticality.

  20. Servo-Drive Amplifier for Micro-Satellite Superconductor-Levitated Flywheels Project

    National Aeronautics and Space Administration — A new servo-drive technology is available to support energy storage and navigation for micro-satellites. Exploiting the ?pinning? effect of high-temperature...

  1. A rough terrain traction control technique for all-wheel-drive mobile robots

    Silva, Alexandre F. Barral; Santos, Auderi Vicente; Meggiolaro, Marco Antonio; Speranza Neto, Mauro


    ... - and guaranteeing an adequate trajectory and speed control while reducing the power requirements. Traction control of all-wheel-drive robots in rough terrain was originally motivated by space exploration, such as in the case of the Mars Exploration Rovers...

  2. New Sensing Application to Diagnose Power Semiconductor Aging in Actuator Power Drive Systems

    National Aeronautics and Space Administration — This paper presents a new sensing application to diagnose power semiconductor aging in power drive systems. It has been shown previously that device parasitic...


    Aaron Mills


    Full Text Available In reflecting on the relationship between ongoing Canadian colonialism and sacred indigenous spaces, the author considers different conceptions of constitutionalism and of law from the location of Gaamitigomishkag, a sacred site for four Anishinaabe communities (including the author’s in the Boundary Waters area of Treaty #3.  The inquiry is framed by the author’s relationship with his grandmother.  In the first section he recalls what it was like learning to learn Anishinaabe law from her.  He invites his readers to join him in shifting their focus from what to how they learn something (perhaps radically new.  In the second section he shares an anecdote about learning from his grandmother on one particular summer day at Gaamitigomishkag.  In the third section, he challenges readers to deploy the interrogative shift from what to how through a narrative that begins to disclose structural differences between Canadian and Anishinaabe constitutionalisms, and thus, their respective systems of law.       Given the narrative form of much of this article, readers have to work for their meanings.  Each arc in the third section’s narrative begins at Gaamitigomishkag, but discloses very different ways that peoples might constitute themselves as political community in, near and through it.  A critical question the article poses is not what, but rather how should one think about community in this space?  The article ends in the present where Canadian constitutionalism has been smashed on top of Anishinaabe constitutionalism.  The author is left at Gaamitigomishkag reflecting on which community(ies he belongs to.  He invites the reader to consider whether he decides.   Dans le cadre de ses réflexions sur la relation entre le colonialisme canadien qui se poursuit et les espaces autochtones sacrés, l’auteur examine diverses conceptions du constitutionnalisme et du droit depuis l’emplacement de « Gaamitigomishkag », qui est un

  4. Investigating hard sphere interactions through spin echo scattering angle measurement

    Washington, Adam

    Spin Echo Scattering Angle Measurement (SESAME) allows neutron scattering instruments to perform real space measurements on large micron scale samples by encoding the scattering angle into the neutron's spin state via Larmor precession. I have built a SESAME instrument at the Low Energy Neutron Source. I have also assisted in the construction of a modular SESAME instrument on the ASTERIX beamline at Los Alamos National lab. The ability to tune these instruments has been proved mathematically and optimized and automated experimentally. Practical limits of the SESAME technique with respect to polarization analyzers, neutron spectra, Larmor elements, and data analysis were investigated. The SESAME technique was used to examine the interaction of hard spheres under depletion. Poly(methyl methacrylate) spheres suspended in decalin had previously been studied as a hard sphere solution. The interparticle correlations between the spheres were found to match the Percus-Yevick closure, as had been previously seen in dynamical light scattering experiments. To expand beyond pure hard spheres, 900kDa polystyrene was added to the solution in concentrations of less than 1% by mass. The steric effects of the polystyrene were expected to produce a short-range, attractive, "sticky" potential. Experiment showed, however, that the "sticky" potential was not a stable state and that the spheres would eventually form long range aggregates.

  5. Birhythmicity and Hard Excitation from Coupled Synthetic Feedback Loops

    Aimin Chen


    Full Text Available Synthetic biology opens up the possibility of creating circuits that would not survive in the natural world and studying their behaviors in living cells, expanding our notion of biology. Based on this, we analyze on a synthetic biological system the effect of coupling between two instability-generating mechanisms. The systems considered are two topologically equivalent synthetic networks. In addition to simple periodic oscillations and stable steady state, the system can exhibit a variety of new modes of dynamic behavior: coexistence between two stable periodic regimes (birhythmicity and coexistence of a stable periodic regime with a stable steady state (hard excitation. Birhythmicity and hard excitation have been proved to exist in biochemical networks. Through bifurcation analysis on these two synthetic cellular networks, we analyze the function of network structure for the collapse and revival of birhythmicity and hard excitation with the variation of parameters. The results have illustrated that the bifurcation space can be divided into four subspaces for which the dynamical behaviors of the system are generically distinct. Our analysis corroborates the results obtained by numerical simulation of the dynamics.

  6. Driving with hemianopia, I: Detection performance in a driving simulator.

    Bowers, Alex R; Mandel, Aaron J; Goldstein, Robert B; Peli, Eli


    This study was designed to examine the effect of homonymous hemianopia (HH) on detection of pedestrian figures in multiple realistic and hazardous situations within the controlled environment of a driving simulator. Twelve people with complete HH and without visual neglect or cognitive decline and 12 matched (age, sex, and years of driving experience) normally sighted (NV) drivers participated. They drove predetermined city and rural highway routes (total, 120 minutes) during which pedestrian figures appeared at random intervals along the roadway (R-Peds; n = 144) and at intersections (I-Peds; n = 10). Detection rates and response times were derived from participant horn presses. Drivers with HH exhibited significantly (P hazard detection.

  7. Space of Spaces

    Anderson, Edward


    Wheeler emphasized the study of Superspace - the space of 3-geometries on a spatial manifold of fixed topology. This is a configuration space for GR; knowledge of configuration spaces is useful as regards dynamics and QM.In this Article I consider furthmore generalized configuration spaces to all levels within the conventional `equipped sets' paradigm of mathematical structure used in fundamental Theoretical Physics. This covers A) the more familiar issue of topology change in the sense of topological manifolds (tied to cobordisms), including via pinched manifolds. B) The less familiar issue of not regarding as fixed the yet deeper levels of structure: topological spaces themselves (and their metric space subcase), collections of subsets and sets. Isham has previously presented quantization schemes for a number of these. I consider some classical preliminaries for this program, aside from the most obvious (classical dynamics for each). Rather, I provide I) to all levels Relational and Background Independence ...

  8. Fundamentals and hard-switching converters

    Ioinovici, Adrian


    Volume 1 Fundamentals and Hard-switching Converters introduces the key challenges in power electronics from basic components to operation principles and presents classical hard- and soft-switching DC to DC converters, rectifiers and inverters. At a more advanced level, it provides comprehensive analysis of DC and AC models comparing the available approaches for their derivation and results. A full treatment of DC to DC hard-switching converters is given, from fundamentals to modern industrial solutions and practical engineering insight. The author elucidates various contradictions and misunderstandings in the literature, for example, in the treatment of the discontinuous conduction operation or in deriving AC small-signal models of converters.

  9. High Amplitude Secondary Mass Drive



    In this paper we describe a high amplitude electrostatic drive for surface micromachined mechanical oscillators that may be suitable for vibratory gyroscopes. It is an advanced design of a previously reported dual mass oscillator (Dyck, et. al., 1999). The structure is a 2 degree-of-freedom, parallel-plate driven motion amplifier, termed the secondary mass drive oscillator (SMD oscillator). During each cycle the device contacts the drive plates, generating large electrostatic forces. Peak-to-peak amplitudes of 54 {micro}m have been obtained by operating the structure in air with an applied voltage of 11 V. We describe the structure, present the analysis and design equations, and show recent results that have been obtained, including frequency response data, power dissipation, and out-of- plane motion.

  10. Drive: Theory and Construct Validation.

    Siegling, Alex B; Petrides, K V


    This article explicates the theory of drive and describes the development and validation of two measures. A representative set of drive facets was derived from an extensive corpus of human attributes (Study 1). Operationalised using an International Personality Item Pool version (the Drive:IPIP), a three-factor model was extracted from the facets in two samples and confirmed on a third sample (Study 2). The multi-item IPIP measure showed congruence with a short form, based on single-item ratings of the facets, and both demonstrated cross-informant reliability. Evidence also supported the measures' convergent, discriminant, concurrent, and incremental validity (Study 3). Based on very promising findings, the authors hope to initiate a stream of research in what is argued to be a rather neglected niche of individual differences and non-cognitive assessment.

  11. Extraordinarily soft, medium-hard and hard Indian wheat varieties: Composition, protein profile, dough and baking properties.

    Katyal, Mehak; Singh, Narpinder; Virdi, Amardeep Singh; Kaur, Amritpal; Chopra, Nidhi; Ahlawat, Arvind Kumar; Singh, Anju Mahendru


    Hard wheat (HW), medium-hard wheat (MHW) and extraordinarily soft wheat (Ex-SW) varieties with grain hardness index (GHI) of 83 to 95, 72 to 80, 17 to 29 were evaluated for pasting, protein molecular weight (MW) distribution, dough rheology and baking properties. Flours from varieties with higher GHI had more protein content, ash content and paste viscosities. Ex-SW had more glutenins proportion as compared to HW and MHW. Flours from Ex-SW varieties showed lower NaSRC, WA and mixographic parameters as compared to HW and MHW. Dough from flours milled from Ex-SW had higher Intermolecular-β-sheets (IM-β-sheets) than those from MHW and HW. Muffins volume increased with decrease in GHI, Ex-SW varieties had more muffin volume and less air space. The accumulation of polypeptides (PPs) varied significantly in different varieties. Ex-SW variety (QBP12-10) showed accumulation of 98, 90, 81 and 79kDa PPs, which was unique and was different from other varieties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Analysis on the Pattern of the House Price and Its Driving Forces in the Dwelling Space in the Urban District of Xi' an%西安市主城区居住空间住宅价格分布格局与驱动机制

    杨瑛; 李同昇; 冯小杰


    In this article, exploring spatial data analyze ( ESDA ) and geographical weighted regression (GWR) was adopted as research method.The spatial pattern and driving forces in Xi' an' s urban district were quantified, and some qualitative discussions were added.The results were as follows.( 1 ) The spatial pattern of density distributions for Xi' an' s new house and second-hand house prices were appeared as it dense higher in the north and south than in the east and west.The dwelling space spatial pattern for new house was organized as three groups, and for second-hand house the pattern was entirely south bias.(2) In the qualitative driving forces ana-lyze, there was not a close relationship between commercial center distance and most dwelling space distributions;the further distance from culture landscape and key middle school, the lower of house price in the dwelling space;the house price was not always higher when it closer to the traffic artery.(3) The industrial layout may affect Xi' an ' s dwelling space distribution;the promotion of city road network density may reduce the traffic factor affection to dwelling space;the house requirement in school district and scenic spot was apparently high;and the new develo-ping hot spot of dwelling space could be formed by policy guidance.In this article, advanced spatial statistic meth-ods were adopted which could efficiently raise the precision.Use the compare between new house and second-hand house was a spatial to temporal method, which could indirectly infer the dwelling space evolution by the present sit-uation of price patterns.%采用探索性空间数据分析法( ESDA)、地理加权回归( GWR)等手段,定量分析西安市主城区居住空间住宅价格分布格局与驱动机制,并辅以定性探讨. 研究结果表明:(1)西安市新房与二手房分布密度呈现城南城北大于城东城西的空间布局形式,新房居住空间呈现出二环以外大明宫—张家堡、曲江—电视塔、

  13. Research on lamellar structure and micro-hardness of directionally solidified Sn-58Bi eutectic alloy

    Hu Xiaowu


    Full Text Available In this work, the Sn-58Bi (weight percent eutectic alloy was directionally solidified at a constant temperature gradient (G = 12 K·mm-1 with different growth rates using a Bridgman type directional solidification furnace. A lamellar microstructure was observed in the Sn-58Bi samples. The lamellar spacing and micro-hardness of longitudinal and transversal sections were measured. The values of lamellar spacing of both longitudinal and transversal sections decrease with an increase in growth rate. The microhardness increases with an increase in the growth rate and decreases with an increase in the lamellar spacing. The dependence of lamellar spacing on growth rate, and micro-hardness on both growth rate and lamellar spacing were obtained by linear regression analysis. The relationships between the lamellar spacing and growth rate, microhardness and growth rate, and micro-hardness and lamellar spacing for transversal and longitudinal sections of Sn-58Bi eutectic alloy were given. The fitted exponent values obtained in this work were compared with the previous similar experimental results and a good agreement was obtained.

  14. Cooperative driving in an intelligent vehicle environment (CO-DRIVE)

    Vonk, T.; Arem, B. van; Hoedemaeker, D.M.


    The Co-Drive project is aimed at the development of an open, in-vehicle research and development ICT-platform for intelligent services. This paper focuses on two of these services: the safety interface with the driver (BIBI) and the dynamic travel guidance. BIBI is a Dutch acronym for Supremely Inte

  15. Digital control of electric drives

    Koziol, R; Szklarski, L


    The electromechanical systems employed in different branches of industry are utilized most often as drives of working machines which must be fed with electric energy in a continuous, periodic or even discrete way. Some of these machines operate at constant speed, others require wide and varying energy control. In many designs the synchronous cooperation of several electric drives is required in addition to the desired dynamic properties. For these reasons the control of the cooperation and dynamics of electromechanical systems requires the use of computers.This book adopts an unusual approach

  16. Driving and Age-Related Macular Degeneration

    Owsley, Cynthia; McGwin, Gerald, Jr.


    This article reviews the research literature on driving and age-related macular degeneration, which is motivated by the link between driving and the quality of life of older adults and their increased collision rate. It addresses the risk of crashes, driving performance, driving difficulty, self-regulation, and interventions to enhance, safety,…

  17. Polar-direct-drive simulations and experiments

    Marozas, J.A.; Marshall, F.J.; Craxton, R.S.; Igumenshchev, I.V.; Skupsky, S.; Bonino, M.J.; Collins, T.J.B.; Epstein, R.; Glebov, V.Yu.; Jacobs-Perkins, D.; Knauer, J.P.; McCrory, R.L.; McKenty, P.W.; Meyerhofer, D.D.; Noyes, S.G.; Radha, P.B.; Sangster, T.C.; Seka, W.; Smalyuk, V.A.


    Polar direct drive (PDD) will allow direct-drive ignition experiments on the National Ignition Facility (NIF) as it is configured for x-ray drive. Optimal drive uniformity is obtained via a combination of beam repointing, pulse shapes, spot shapes, and/or target design. This article describes progress in the development of standard and "Saturn" PDD target designs.

  18. Roller/Gear Drives For Robotic Manipulators

    Anderson, William J.; Shipitalo, William


    Pitch/yaw roller/gear drive and wrist-roll roller/gear drive designed to incorporate several features desirable in robotic-joint actuators. Includes zero backlash, high efficiency, smooth motion (little ripple in torque and in speed ratio), and high degree of back-drivability. Pitch/yaw drive is novel two-axis drive containing combination of gears, rollers, and springs acting together eliminating backlash and cogging. Wrist-roll drive more-conventional single-axis drive offering advantages like those of pitch/yaw drive.

  19. Electronic 4-wheel drive control device

    Hayato, S.; Takanori, S.; Shigeru, H.; Tatsunori, S.


    The internal rotation torque generated during operation of a 4-wheel drive vehicle is reduced using a control device whose clutch is attached to one part of the rear-wheel drive shaft. One torque sensor senses the drive torque associated with the rear wheel drive shaft. A second sensor senses the drive torque associated with the front wheel drive shaft. Revolution count sensors sense the revolutions of each drive shaft. By means of a microcomputer, the engagement of the clutch is changed to insure that the ratio of the torque sensors remains constant.

  20. A new technology for hard-rock tunneling based on drilling and hydraulic impact breaking

    Long Risheng; Sun Shaoni; Lian Zisheng; Liao Yaoyao; Qin Xiaofeng


    In order to realize the safety, high efficiency and rapidity of hard rock tunneling, we propose the drilling&hydraulic impact hard-rock tunneling (DHIHT) technology and method. Based on the LS-DYNA explicit module and APDL programming, the key parameters of DHIHT, including drilling spacing and drilling radius, were investigated. The simulation results show that: the drilling spacing should not exceed 0.20 m-larger distances weaken the actual breaking effect;the best drilling radius is about 0.035 m, lar-ger or smaller distances would both decrease the effect of drilling-hole free surfaces. The field impact breaking experiments were conducted in Baitaizi township granite quarry, Jinzhou, Liaoning province, China. The experiment results indicate that DHIHT is a feasible method for hard-rock tunneling, but its efficiency still needs to be further optimized and improved.

  1. Magnetic Space Launcher

    Bolonkin, Alexander


    A method and facilities for delivering payload and people into outer space are presented. This method uses, in general, engines located on a planetary surface. The installation consists of a space apparatus, power drive stations, which include a flywheel accumulator (for storage) of energy, a variable reducer, a powerful homopolar electric generator and electric rails. The drive stations accelerate the apparatus up to hypersonic speed. The estimations and computations show the possibility of making this project a reality in a short period of time (for payloads which can tolerate high g-forces). The launch will be very cheap at a projected cost of 3 - 5 dollars per pound. The authors developed a theory of this type of the launcher.

  2. Analytic studies of the hard dumbell fluid

    Morriss, G. P.; Cummings, P. T.

    A closed form analytic theory for the structure of the hard dumbell fluid is introduced and evaluated. It is found to be comparable in accuracy to the reference interaction site approximation (RISA) of Chandler and Andersen.

  3. Why Are Drugs So Hard to Quit?

    Full Text Available ... it free Find out why Close Why Are Drugs So Hard to Quit? National Institute on Drug Abuse (NIDA/NIH) Loading... Unsubscribe from National Institute on Drug Abuse (NIDA/NIH)? Cancel Unsubscribe Working... Subscribe Subscribed ...

  4. Why Are Drugs So Hard to Quit?

    Full Text Available ... navigation Sign in Search Loading... Close Yeah, keep it Undo Close This video is unavailable. Watch Queue ... changes the signals in your brain and makes it hard to feel OK without the drug. This ...

  5. Why Are Drugs So Hard to Quit?

    Full Text Available ... Feb 7, 2012 Quitting drugs is hard because addiction is a brain disease. Your brain is like ... out signals to direct your actions and choices. Addiction changes the signals in your brain and makes ...

  6. Event Driven Langevin simulations of Hard Spheres

    Scala, Antonio


    The blossoming of interest in colloids and nano-particles has given renewed impulse to the study of hard-body systems. In particular, hard spheres have become a real test system for theories and experiments. It is therefore necessary to study the complex dynamics of such systems in presence of a solvent; disregarding hydrodynamic interactions, the simplest model is the Langevin equation. Unfortunately, standard algorithms for the numerical integration of the Langevin equation require that interactions are slowly varying during an integration timestep. This in not the case for hard-body systems, where there is no clearcut between the correlation time of the noise and the timescale of the interactions. Starting first from a splitting of the Fokker-Plank operator associated with the Langevin dynamics, and then from an approximation of the two-body Green's function, we introduce and test two new algorithms for the simulation of the Langevin dynamics of hard-spheres.

  7. Hard target LIDAR calibration for SO2

    Du Plessis, A


    Full Text Available Presentation on hard target LIDAR calibration for SO2. This project aimed at measuring the concentration of the atmospheric pollutants such as gases and mobile laser system for remote detection...

  8. Why Are Drugs So Hard to Quit?

    Full Text Available ... later? Sign in to add this video to a playlist. Sign in Share More Report Need to ... 2012 Quitting drugs is hard because addiction is a brain disease. Your brain is like a control ...

  9. Optical waveguides in hard crystalline materials

    Pollnau, M.


    The recent results of our research group and collaborators in the field of fabrication, characterization, and applications of optical waveguides in hard crystalline materials, specifically in sapphire and Ti:sapphire, are reviewed.

  10. Why Is It So Hard to Quit?

    ... to quit? It’s hard to tackle the physical addiction to nicotine . Cigarettes contain nicotine, a highly addictive ... a support group can give you comfort and positive reinforcement. Cut back on caffeine . Caffeine is a ...

  11. Standard test methods for rockwell hardness of metallic materials

    American Society for Testing and Materials. Philadelphia


    1.1 These test methods cover the determination of the Rockwell hardness and the Rockwell superficial hardness of metallic materials by the Rockwell indentation hardness principle. This standard provides the requirements for Rockwell hardness machines and the procedures for performing Rockwell hardness tests. 1.2 This standard includes additional requirements in annexes: Verification of Rockwell Hardness Testing Machines Annex A1 Rockwell Hardness Standardizing Machines Annex A2 Standardization of Rockwell Indenters Annex A3 Standardization of Rockwell Hardness Test Blocks Annex A4 Guidelines for Determining the Minimum Thickness of a Test Piece Annex A5 Hardness Value Corrections When Testing on Convex Cylindrical Surfaces Annex A6 1.3 This standard includes nonmandatory information in appendixes which relates to the Rockwell hardness test. List of ASTM Standards Giving Hardness Values Corresponding to Tensile Strength Appendix X1 Examples of Procedures for Determining Rockwell Hardness Uncertainty Appendix X...

  12. Standard test methods for rockwell hardness of metallic materials

    American Society for Testing and Materials. Philadelphia


    1.1 These test methods cover the determination of the Rockwell hardness and the Rockwell superficial hardness of metallic materials by the Rockwell indentation hardness principle. This standard provides the requirements for Rockwell hardness machines and the procedures for performing Rockwell hardness tests. 1.2 This standard includes additional requirements in annexes: Verification of Rockwell Hardness Testing Machines Annex A1 Rockwell Hardness Standardizing Machines Annex A2 Standardization of Rockwell Indenters Annex A3 Standardization of Rockwell Hardness Test Blocks Annex A4 Guidelines for Determining the Minimum Thickness of a Test Piece Annex A5 Hardness Value Corrections When Testing on Convex Cylindrical Surfaces Annex A6 1.3 This standard includes nonmandatory information in appendixes which relates to the Rockwell hardness test. List of ASTM Standards Giving Hardness Values Corresponding to Tensile Strength Appendix X1 Examples of Procedures for Determining Rockwell Hardness Uncertainty Appendix X...

  13. Hardness and Methods to Solve CLIQUE

    ZHU Daming; LUAN Junfeng; MA Shaohan


    The paper briefly reviews NP-hard optimization problems and their inapproximability. The hardness of solving CLIQUE problem is specifically discussed. A dynamic-programming algorithm and its improved version for CLIQUE are reviewed and some additional analysis is presented. The analysis implies that the improved algorithm, HEWN (hierarchical edge-weighted network), only provides a heuristic or useful method, but cannot be called a polynomial algorithm.

  14. A Novel Approach to Hardness Testing

    Spiegel, F. Xavier; West, Harvey A.


    This paper gives a description of the application of a simple rebound time measuring device and relates the determination of relative hardness of a variety of common engineering metals. A relation between rebound time and hardness will be sought. The effect of geometry and surface condition will also be discussed in order to acquaint the student with the problems associated with this type of method.

  15. The Chiral Dipolar Hard Sphere Model.

    Mazars, Martial


    Abstract A simple molecular model of chiral molecules is presented in this paper : the chiral dipolar hard sphere model. The discriminatory interaction between enantiomers is represented by electrostatic (or magnetic) dipoles-dipoles interactions : short ranged steric repulsion are represented by hard sphere potential and, in each molecule, two point dipoles are located inside the sphere. The model is described in detail and some of its elementary properties are given ; in particul...

  16. Point defects in hard-sphere crystals

    Pronk, S.; Frenkel, D.


    We report numerical calculations of the concentration of interstitials in hard-sphere crystals. We find that, in a three-dimensional fcc hard-sphere crystal at the melting point, the concentration of interstitials is 2 * 10^-8. This is some three orders of magnitude lower than the concentration of vacancies. A simple, analytical estimate yields a value that is in fair agreement with the numerical results.

  17. Space Exploration

    Gallagher, Dennis


    New range Passage Tomb may be the first structure with known astronomical significance. It was built around 3,200 B.C. in Ireland. It's central passage allows light end-to-end for about 2 weeks around winter solstice. The Sun, Moon, Planets, and Stars held significance in early times due to the seasons, significance for food crops, and mythology. Citation: Corel Photography and Windows to the Universe The Greek may be among the first to pursue analytical interpretations of what they saw in the sky. In about 280 B.C. Aristarchus suggested Earth revolves around the Sun and estimated the distance between. Around 130 B.C. Hipparchus developed the first accurate star map. Today still seek to understand how the universe formed and how we came to be and are we alone. Understanding the causes and consequences of climate change using advanced space missions with major Earth science and applications research. center dotFire the public imagination and inspire students to pursue STEM fields. Train college and graduate students to create a U.S. technical workforce with employees that embody the values of competence, innovation, and service. center dotDrive the technical innovations that enable exploration and become the engine of National economic growth. center dotPartner domestically and internationally to leverage resources to extend the reach of research.

  18. Water drives peptide conformational transitions

    Nerukh, Dmitry


    Transitions between metastable conformations of a dipeptide are investigated using classical molecular dynamics simulation with explicit water molecules. The distribution of the surrounding water at different moments before the transitions and the dynamical correlations of water with the peptide's configurational motions indicate that water is the main driving force of the conformational changes.

  19. Foreign driving licences in Switzerland

    DG Unit


    1. Persons residing in Switzerland 1.1 Holders of a B, C, D, E or P-type "carte de légitimation" For holders of a B, C, D, E or P-type "carte de légitimation" issued by the Swiss Federal Department for Foreign Affairs (DFAE), current non-Swiss national driving licences are valid in Switzerland. If they so wish, holders of such driving licences may apply to the relevant road licensing authority in the canton where they live (Service des Automobiles et de la Navigation; for Geneva call + 41 22 388 30 30, website; for Vaud call + 41 21 316 82 10, website to exchange their driving licence for an equivalent Swiss licence (they must pass a test if they are not citizens of countries with which Switzerland has concluded an agreement on this matter, e.g. Member States of the European Union, the United States and Japan). However, such an exchange is not possible if the driving licence was issued in a foreign country during a...


    Relatiopns with the Host States Service


    1. PERSONS RESIDING IN SWITZERLAND 1.1 Holders of a B, C, D or E-type carte de légitimation For holders of B, C, D or E-type cartes de légitimation issued by the Swiss Federal Department for Foreign Affairs (Département fédéral suisse des Affaires étrangères, hereinafter called DFAE), current non-Swiss national driving licences are valid in Switzerland. Should they so wish, holders of such driving licences may apply to the relevant roads authority in the canton where they live (Service des Automobiles et de la Navigation ; for Geneva call 022/343 02 00, website:, for Vaud call 021/316 82 10, website: in order to exchange their driving licence for an equivalent Swiss licence. However, exchanges are not permitted if the driving licence was issued in a foreign country during a stay there of less than six months' duration while the person concerned was officially...

  1. CLIC Drive Beam Accelerating Structures

    Wegner, Rolf


    Travelling structures for accelerating the high-current (4.2 A) CLIC Drive Beam to an energy of 2.37 GeV are presented. The structures are optimised for efficiency (full beam loading operation) and a desired filling time. Higher order modes are studied and are reduced by detuning along the structure and by damping with silicon carbide loads.

  2. Police enforcement and driving speed.


    Speed limits are violated frequently in the Netherlands. As speed is an important factor in road crashes, the surveillance of driving speeds is one of the spearheads in the policy plans of the Dutch police. Different methods of speed enforcement have proved to be effective in reducing speed and cras

  3. Death Drive in Tourism Studies

    Buda, Dorina


    The psychoanalytical concept of the death drive refers to a constant metapsychological force at the junction between life and death: it is not understood in a biological sense of physical demise of the body, nor in opposition to life. Geographies of tourist performances in places in the proximity of

  4. Heavy consumption and drink driving

    Fynbo, Lars


    on the interviewee’s risk behaviour, especially in relation to driving. The interviewees are first divided into 1) a group of young “edgeworkers” with pronounced general risk behaviour, 2) a group of middle-aged “post-edgeworkers”, most with criminal records, and 3) a group of middle-aged and older heavy consumers...

  5. Death Drive in Tourism Studies

    Buda, Dorina


    The psychoanalytical concept of the death drive refers to a constant metapsychological force at the junction between life and death: it is not understood in a biological sense of physical demise of the body, nor in opposition to life. Geographies of tourist performances in places in the proximity of

  6. Torque-Splitting Gear Drive

    Kish, J.


    Geared drive train transmits torque from input shaft in equal parts along two paths in parallel, then combines torques in single output shaft. Scheme reduces load on teeth of meshing gears while furnishing redundancy to protect against failures. Such splitting and recombination of torques common in design of turbine engines.

  7. Digital control of electrical drives

    Vukosavic, Slobodan N


    Offers insight into electric drives and their usage in motion control environment. This book provides links among electrical machine and control theory, practical hardware aspects, programming issues, and application-specific problems. It covers the key elements of motion control systems, and discrete-time speed and position controllers.

  8. Sensory drive in cichlid speciation

    Maan, Martine E.; Hofker, Kees D.; van Alphen, Jacques J. M.; Seehausen, Ole


    The role of selection in speciation is a central yet poorly understood problem in evolutionary biology. The rapid radiations of extremely colorful cichlid fish in African lakes have fueled the hypothesis that sexual selection can drive species divergence without geographical isolation. Here we prese

  9. Modular Actuators for Space Applications Project

    National Aeronautics and Space Administration — Rocketstar Robotics is proposing the development of a modern dual drive actuator. Rocketstar has put together numerous modern concepts for modular actuators that...

  10. 11th International Conference on Large Scale Applications and Radiation Hardness of Semiconductor Detectors


    The conference will focus on semiconductor detectors issues relevant to applications in accelerator and space research. Topics include: - large semiconductor systems for calorimetry and tracking applications; - radiation damage measurements and modeling; - radiation hardness of semiconductor detectors; - innovative detectors and electronic systems.

  11. Numerical Analysis and Experimental Study of Hard Roofs in Fully Mechanized Mining Faces under Sleeve Fracturing

    Zhitao Zheng


    Full Text Available Sudden falls of large-area hard roofs in a mined area release a large amount of elastic energy, generate dynamic loads, and cause disasters such as impact ground pressure and gas outbursts. To address these problems, in this study, the sleeve fracturing method (SFM was applied to weaken a hard roof. The numerical simulation software FLAC3D was used to develop three models based on an analysis of the SFM working mechanism. These models were applied to an analysis of the fracturing effects of various factors such as the borehole diameter, hole spacing, and sleeve pressure. Finally, the results of a simulation were validated using experiments with similar models. Our research indicated the following: (1 The crack propagation directions in the models were affected by the maximum principal stress and hole spacing. When the borehole diameter was fixed, the fracturing pressure increased with increasing hole spacing. In contrast, when the fracturing pressure was fixed, the fracturing range increased with increasing borehole diameter; (2 The most ideal fracturing effect was found at a fracturing pressure of 17.6 MPa in the model with a borehole diameter of 40 mm and hole spacing of 400 mm. The results showed that it is possible to regulate the falls of hard roofs using the SFM. This research may provide a theoretical basis for controlling hard roofs in mining.

  12. Inclusion of Radiation Environment Variability in Total Dose Hardness Assurance Methodology

    Xapsos, M. A.; Stauffer, C.; Phan, A.; McClure, S. S.; Ladbury, R. L.; Pellish, J. A.; Campola, M. J.; LaBel, K. A.


    Variability of the space radiation environment is investigated with regard to parts categorization for total dose hardness assurance methods. It is shown that it can have a significant impact. A modified approach is developed that uses current environment models more consistently and replaces the design margin concept with one of failure probability.

  13. Development of grazing incidence multilayer mirrors for hard X-ray focusing telescopes

    Mao, Peter H.; Harrison, Fiona A.; Platonov, Yuriy Y.


    We are developing depth-graded, multilayer-coated mirrors for astrophysical hard X-ray focusing telescopes. In this paper, we discuss the primary technical challenges associated with the multilayer coatings, and report on progress to date. We have sputtered constant d-spacing and depth-graded W...

  14. Direct observation of dynamical heterogeneities in colloidal hard-sphere suspensions

    Kegel, W.K.; Blaaderen, A. van


    The real-space dynamics in a model system of colloidal hard spheres was studied by means of time-resolved ßuorescence confocal scanning microscopy. Direct experimental evidence for the presence of dynamical heterogeneities in a dense liquid was obtained from an analysis of particle trajectories in t

  15. Multilayer coating facility for the HEFT hard x-ray telescope

    Cooper-Jensen, Carsten P.; Christensen, Finn Erland; Chen, Hubert


    A planar magnetron sputtering facility has been established at the Danish Space Research Institute (DSRI) for the production coating of depth graded multilayers on the thermally slumped glass segments which form the basis for the hard X-ray telescope on the HEFT balloon project. The facility...

  16. Application of an EMCCD camera for calibration of hard X-ray telescopes

    Vogel, Julia K.; Pivovaro, Michael J.; Craig, William W.


    Recent technological innovations make it feasible to construct effcient hard x-ray telescopes for space-based astronomical missions. Focusing optics are capable of improving the sensitivity in the energy range above 10 keV by orders of magnitude compared to previously used instruments. The last d...

  17. Hard and Soft Multilayered SiCN Nanocoatings with High Hardness and Toughness

    S. K. Mishra


    Full Text Available Alternate hard and soft layers increase deformation accommodation as thin hard layers slide relative to each other due to shear deformation of low modulus layers. However, the processing of such multilayers is challenging. In the present paper the alternating soft and hard multilayered SiCN coating deposited by magnetron sputtering has been studied and presented. A hardness and modulus of 37 GPa and 317 GPa with elastic recovery of 62% are achieved by alternate hard and soft layer of Si–C–N by magnetron sputtering. The trilayer films sustained even 2000 gf under indentation without failure though substrate plastically deformed. The fracture toughness value KIC was measured to be 9.5–10 MPa m1/2, significantly higher than many reported hard coatings.

  18. Enhanced Lower Hybrid Current Drive Experiments on HT-7 Tokamak


    Effective Lower Hybrid Current Driving (LHCD) and improved confinement exper-iments in higher plasma parameters (Ip > 200 kA, ne> 2×1013 cm-3, Te ≥ 1 keⅤ) havebeen curried out in optimized LH wave spectrum and plasma parameters in HT-7 supercon-ducting tokamak. The dependence of current driving efficiency on LH power spectrum, plasmadensity ne and toroidal magnetic field BT has been obtained under optimal conditions. A goodCD efficiency was obtained at higher plasma current and higher electron density. The improve-ment of the energy confinement time is accompanied with the increase in line averaged electrondensity, and in ion and electron temperatures. The highest current driving efficiency reachedηCD = IpneR/PRF ≈ 1.05 × 1019 Am-2/W. Wave-plasma coupling was sustained in a good stateand the reflective coefficient was less than 5%. The experiments have also demonstrated the abilityof LH wave in the start-up and ramp-up of the plasma current. The measurement of the temporaldistribution of plasma parameter shows that lower hybrid leads to a broader profile in plasmaparameter. The LH power deposition profile and the plasma current density profile were modeledwith a 2D Fokker-Planck code corresponding to the evolution process of the hard x-ray detectorarray.

  19. Computer Tensor Codes to Design the War Drive

    Maccone, C.

    To address problems in Breakthrough Propulsion Physics (BPP) and design the Warp Drive one needs sheer computing capabilities. This is because General Relativity (GR) and Quantum Field Theory (QFT) are so mathematically sophisticated that the amount of analytical calculations is prohibitive and one can hardly do all of them by hand. In this paper we make a comparative review of the main tensor calculus capabilities of the three most advanced and commercially available “symbolic manipulator” codes. We also point out that currently one faces such a variety of different conventions in tensor calculus that it is difficult or impossible to compare results obtained by different scholars in GR and QFT. Mathematical physicists, experimental physicists and engineers have each their own way of customizing tensors, especially by using different metric signatures, different metric determinant signs, different definitions of the basic Riemann and Ricci tensors, and by adopting different systems of physical units. This chaos greatly hampers progress toward the design of the Warp Drive. It is thus suggested that NASA would be a suitable organization to establish standards in symbolic tensor calculus and anyone working in BPP should adopt these standards. Alternatively other institutions, like CERN in Europe, might consider the challenge of starting the preliminary implementation of a Universal Tensor Code to design the Warp Drive.

  20. Driver headway choice : A comparison between driving simulator and real-road driving

    Risto, M.; Martens, M.H.


    Driving simulators have become an established tool in driver behaviour research by offering a controllable, safe and cost-effective alternative to real world driving. A challenge for using driving simulators as a research tool has been to elicit driving behaviour that equals real world driving. With

  1. Driver headway choice: a comparison between driving simulator and real-road driving

    Risto, Malte; Martens, Marieke Hendrikje


    Driving simulators have become an established tool in driver behaviour research by offering a controllable, safe and cost-effective alternative to real world driving. A challenge for using driving simulators as a research tool has been to elicit driving behaviour that equals real world driving. With

  2. Developing and Studying the Methods of Hard-Facing with Heat-Resisting High-Hardness Steels

    Malushin, N. N.; Kovalev, A. P.; Valuev, D. V.; Shats, E. A.; Borovikov, I. F.


    The authors develop the methods of hard-facing of mining-metallurgic equipment parts with heat-resisting high-hardness steels on the base of plasma-jet hard-facing in the shielding-alloying nitrogen atmosphere.

  3. Why Space is Unique? The Basic Environment Challenges for EEE Parts

    LaBel, Kenneth A.; Sampson, Michael J.


    This presentation includes an introduction the space radiation environment, the effects on electronics, the environment in action, flight projects, mission needs, and radiation hardness assurance (RHA).

  4. Current drive experiments in the Helicity Injected Torus - II

    Hamp, W. T.; Redd, A. J.; Jarboe, T. R.; Nelson, B. A.; O'Neill, R. G.; Raman, R.; Sieck, P. E.; Smith, R. J.; Mueller, D.


    The HIT-II spherical torus (ST) device has demonstrated four toroidal plasma current drive configurations to form and sustain a tokamak: 1) inductive (ohmic) current drive, 2) coaxial helicity injection (CHI) current drive, 3) CHI initiated plasmas with ohmic sustainment (CHI+OH), and 4) ohmically initiated plasmas with CHI edge current drive (OH+ECD). CHI discharges with a sufficiently high ratio of injector current to toroidal field current form a closed flux core, and amplify the injector poloidal flux through magnetic reconnection. CHI+OH plasmas are more robust than unassisted ohmic discharges, with a wider operating space and more efficient use of the transformer Volt-seconds. Finally, edge CHI can enhance the plasma current of an ohmic discharge without significantly degrading the quality of the discharge. Results will be presented for each HIT-II operating regime, including empirical performance scalings, applicable parametric operating spaces, and requirements to produce these discharges. Thomson scattering measurements and EFIT simulations are used to evaluate confinement in several representative plasmas. Finally, we outline extensions to the HIT-II CHI studies that could be performed with NSTX, SUNIST, or other ST devices.

  5. Measurement of electron energy distribution from X-rays diagnostics - foil techniques used with the hard X-ray camera on PBX-M

    Goeler, S. von; Bell, R.; Bernabei, S.; Davis, W.; Ignat, D. [and others


    A half-screen foil technique is used with the Hard X-ray Camera on the PBX-M tokamak to determine the energy distribution of the suprathermal electrons generated during lower hybrid current drive. The ratio of perpendicular to parallel temperature of the suprathermal electrons is deduced from the anisotropy of the bremsstrahlung emission utilizing Abel inversion techniques. Results from lower hybrid current drive discharges are discussed.

  6. Arbitrary quantum state engineering in three-state systems via Counterdiabatic driving

    Chen, Ye-Hong; Wu, Qi-Cheng; Huang, Bi-Hua; Song, Jie; Xia, Yan


    A scheme for arbitrary quantum state engineering (QSE) in three-state systems is proposed. Firstly, starting from a set of complete orthogonal time-dependent basis with undetermined coefficients, a time-dependent Hamiltonian is derived via Counterdiabatic driving for the purpose of guiding the system to attain an arbitrary target state at a predefined time. Then, on request of the assumed target states, two single-mode driving protocols and a multi-mode driving protocol are proposed as examples to discuss the validity of the QSE scheme. The result of comparison between single-mode driving and multi-mode driving shows that multi-mode driving seems to have a wider rang of application prospect because it can drive the system to an arbitrary target state from an arbitrary initial state also at a predefined time even without the use of microwave fields for the transition between the two ground states. Moreover, for the purpose of discussion in the scheme’s feasibility in practice, a polynomial ansatz as the simplest exampleis used to fix the pulses. The result shows that the pulses designed to implement the protocols are not hard to be realized in practice. At the end, QSE in higher-dimensional systems is also discussed in brief as a generalization example of the scheme.

  7. Model Based Incipient Fault Detection for Gear Drives


    This paper presents the method of model based incipient fault detection for gear drives,this method is based on parity space method. It can generate the robust residual that is maximally sensitive to the fault caused by the change of the parameters. The example of simulation shows the application of the method, and the residual waves have different characteristics due to different parameter changes; one can detect and isolate the fault based on the different characteristics.

  8. Ontology-Based Context Awareness for Driving Assistance Systems

    Armand, Alexandre; Filliat, David; Ibañez-Guzman, Javier


    International audience; Within a vehicle driving space, different entities such as vehicles and vulnerable road users are in constant interaction. That governs their behaviour. Whilst smart sensors provide information about the state of the perceived objects, considering the spatio-temporal relationships between them with respect to the subject vehicle remains a challenge. This paper proposes to fill this gap by using contextual information to infer how perceived entities are expected to beha...

  9. Forecasting methods for occurrence and magnitude of proton storms with solar hard X rays

    Garcia, H. A.


    A hard X-ray spectrometer (HXRS) was developed jointly by the National Oceanic and Atmospheric Administration (NOAA) Space Environment Center and the Astronomical Institute of the Czech Republic to determine if proton storms could be forecast with greater accuracies than presently available by the existing methods. The HXRS experiment was conceived as a means of proof testing previously discovered empirical relationships between anomalous hard X-ray spectra of hard X-ray flares and solar energetic proton events (SEPs) for space weather forecasting applications. SEPs are showers of highly energetic electrons and ions, mostly protons, that can reach Earth's vicinity within minutes to hours following a moderate to large flare and have the potential of affecting the performance of civilian, military and research satellites as well as certain surface assets. The primary SEP predictor criterion educed during the present study is the requirement that the spectral index, γ, must decline (harden) to at least <=4 for at least 3 min. Flares meeting this criterion have a high association with SEPs. Flares that fail this criterion do not. Other SEP correlative phenomena such as depressed hard X-ray flux and anomalous low temperatures were studied to determine their utility for forecasting purposes. During the study period, March 2000 through December 2002, 107 hard X-ray flares were spectrally analyzed including 16 SEP-associated flares. Fourteen SEP flares were correctly identified, two SEPs were missed, and three false alarms (untrue predictions) were incurred.

  10. Fault Tolerant, Radiation hard DSP Project

    National Aeronautics and Space Administration — Commercial digital signal processors (DSP) are problematic for satellite computers due to damaging space radiation effects, particularly single event upsets (SEU)...

  11. Fast electron dynamics in lower hybrid current drive experiment on HT-7 tokamak

    Shi Yue-Jiang; Kuang Gang-Li; Li Jian-Gang; HT-7 Team; Wan Bao-Nian; Chen Zhong-Yong; Hu Li-Qun; Lin Shi-Yao; Ruan Huai-Lin; Qian Jin-Ping; Zhen Xiang-Jun; Ding Bo-Jiang


    The dynamic behaviour of fast electron in lower hybrid current drive (LHCD) experiments is a crucial issue in the sense of enhancing plasma performance. A new hard x-ray diagnostic system on HT-7 allows the investigation of the lower hybrid wave dynamics. The behaviour of fast electron is studied in several kinds of LHCD experiments, including long pulse discharges, high performance discharges and counter-LHCD experiments.

  12. The warp drive and antigravity

    Ellis, H G


    The warp drive envisioned by Alcubierre that can move a spaceship faster than light can, with modification, levitate it as if it were lighter than light, even allow it to go below a black hole's horizon and return unscathed. Wormhole-like versions of the author's `drainhole' (1973) might provide the drive, in the form of a by-pass of the spaceship composed of a multitude of tiny topological tunnels. The by-pass would divert the gravitational `ether' into a sink covering part of the spaceship's hull, connected by the tunnels to a source covering the remainder of the hull, to produce an ether flow like that of a river that disappears underground only to spring forth at a point downstream. This diversion would effectively shield the spaceship from external gravity.

  13. Conditional dynamics driving financial markets

    Boguñá, M.; Masoliver, J.


    We revisit the problem of daily correlations in speculative prices and report empirical evidences on the existence of what we term a conditional or dual dynamics driving the evolution of financial assets. This dynamics is detected in several markets around the world and for different historical periods. In particular, we have analyzed the DJIA database from 1900 to 2002 as well as 65 companies trading in the LIFFE market of futures and 12 of the major European and American treasury bonds. In all cases, we find a twofold dynamics driving the financial evolution depending on whether the previous price went up or down. We conjecture that this effect is universal and intrinsic to all markets.

  14. Opportunities and Cooperation Drive Prosperity


    The old industrial base is lying in Northeast China. Although boasting many advantages such as talents, resources, transportation, environment, the region still have many disadvantages that needs opening up and reform. Revitalizing the Northeast region is an important task for China to built well-off society in an all-round way in the new century. It is also a big strategy made after developing costal region and western region by Chinese leaders according to current situation, which is a driving force


    Service des relations avec les Pays Hôtes


    1. PERSONS RESIDING IN FRANCE1.1 National driving licences from countries belonging to the EEAa) ValidityCurrent national driving licences issued by a country belonging to the European Economic Area (here inafter called EEA) are, in principle, valid in France. N.B. : The countries belonging to the EEA are Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Liechtenstein, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden and the United Kingdom.b)\tRegistrationTo ensure that all the conditions of validity in France have been met, holders of driving licences issued by a country belonging to the EEA, who reside in France (i.e. hold a residence permit issued by a Préfecture, or a carte spéciale issued by the French Ministry of Foreign Affairs, which is equivalent to a residence permit), can have their licences registered with the Préfecture of the department where they live (for Ain, call 04 74 32 30 00, for Haute Savoie call 04 50 33 ...

  16. Foreign driving licences in France

    HR Department


    The following information is subject to possible amendments decided by the competent French authorities. Those wishing to undertake the necessary steps with the prefectural services of the Departments of the Ain and Haute-Savoie may obtain information by calling the following numbers: + 33 4 74 32 30 65 for the Ain and + 33 4 50 33 60 00 for Haute-Savoie. 1. PERSONS RESIDING IN FRANCE 1.1 Driving licences issued by a State belonging to the EU or the EEA a) Recognition on French territory All currently valid driving licences issued by States belonging to the European Union (EU) or to the European Economic Area (EEA) are generally valid for driving on French territory. However, if the licence was originally obtained in exchange for a licence issued by a State not belonging to the EU or to the EEA and with which France has not concluded a reciprocity agreement, it will be recognised for a maximum of one year following the date of establishment of normal residence in France ...


    DSU Unit


    The following information is provided subject to possible amendments decided by the competent French authorities. Those wishing to undertake the necessary steps with the prefectural services of the Departments of Ain and Haute-Savoie may obtain information by calling the following numbers: + 33 474 32 30 65 for Ain and + 33 450 33 60 00 for Haute-Savoie. 1. PEOPLE RESIDING IN FRANCE 1.1 Driving licences issued by a state belonging to the EU or the EEA a) Recognition on French territory All currently valid driving licences issued by States belonging to the European Union (EU) or to the European Economic Area (EEA) are generally valid for driving on French territory. However, if the licence was originally obtained in exchange for a licence issued by a State not belonging to the EU or to the EEA with which France has not concluded a reciprocity agreement, it is recognised only up to one year following the date of establishment of normal residence in France (date of the first special residence permit issu...

  18. Foreign driving licences in Switzerland


    1. Persons residing in Switzerland 1.1 Holders of a B, C, D, E or P-type "carte de légitimation" For holders of a B, C, D, E or P-type "carte de légitimation" issued by the Swiss Federal Department for Foreign Affairs (DFAE), current non-Swiss national driving licences are valid in Switzerland. (see the official news about the new "Carte de légitimation P") If they so wish, holders of such driving licences may apply to the relevant road licensing authority in the canton where they live (Service des Automobiles et de la Navigation; for Geneva call + 41 22 388 30 30, website; for Vaud call + 41 21 316 82 10, website to exchange their driving licence for an equivalent Swiss licence (they must pass a test if they are not citizens of countries with which Switzerland has concluded an agreement on this matter, e.g. Member States of the European Union, the United States and Japan). However, such an exchange is not possible...

  19. Research in the Hard Sciences, and in Very Hard "Softer" Domains

    Phillips, D. C.


    The author of this commentary argues that physical scientists are attempting to advance knowledge in the so-called hard sciences, whereas education researchers are laboring to increase knowledge and understanding in an "extremely hard" but softer domain. Drawing on the work of Popper and Dewey, this commentary highlights the relative…

  20. Hard Water and Soft Soap: Dependence of Soap Performance on Water Hardness

    Osorio, Viktoria K. L.; de Oliveira, Wanda; El Seoud, Omar A.; Cotton, Wyatt; Easdon, Jerry


    The demonstration of the performance of soap in different aqueous solutions, which is due to water hardness and soap formulation, is described. The demonstrations use safe, inexpensive reagents and simple glassware and equipment, introduce important everyday topics, stimulates the students to consider the wider consequences of water hardness and…