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1.
Guest Editor's Introduction 总被引:1,自引:0,他引:1
Eduard Ayguade 《International journal of parallel programming》2003,31(3):181-183
2.
We propose a method for non-uniform reconstruction of 3D scalar data. Typically, radial basis functions, trigonometric polynomials or shift-invariant functions are used in the functional approximation of 3D data. We adopt a variational approach for the reconstruction and rendering of 3D data. The principle idea is based on data fitting via thin-plate splines. An approximation by B-splines offers more compact support for fast reconstruction. We adopt this method for large datasets by introducing a block-based reconstruction approach. This makes the method practical for large datasets. Our reconstruction will be smooth across blocks. We give reconstruction measurements as error estimations based on different parameter settings and also an insight on the computational effort. We show that the block size used in reconstruction has a negligible effect on the reconstruction error. Finally we show rendering results to emphasize the quality of this 3D reconstruction technique. 相似文献
3.
An appropriate assessment of end-to-end network performance presumes highly efficient time tracking and measurement with precise time control of the stopping and resuming of program operation. In this paper, a novel approach to solving the problems of highly efficient and precise time measurements on PC-platforms and on ARM-architectures is proposed. A new unified High Performance Timer and a corresponding software library offer a unified interface to the known time counters and automatically identify the fastest and most reliable time source, available in the user space of a computing system. The research is focused on developing an approach of unified time acquisition from the PC hardware and accordingly substituting the common way of getting the time value through Linux system calls. The presented approach provides a much faster means of obtaining the time values with a nanosecond precision than by using conventional means. Moreover, it is capable of handling the sequential time value, precise sleep functions and process resuming. This ability means the reduction of wasting computer resources during the execution of a sleeping process from 100% (busy-wait) to 1-1.5%, whereas the benefits of very accurate process resuming times on long waits are maintained. 相似文献
4.
Adelina-Gabriela Niculescu Dan Eduard Mihaiescu Alexandru Mihai Grumezescu 《International journal of molecular sciences》2022,23(15)
Microfluidics is defined as emerging science and technology based on precisely manipulating fluids through miniaturized devices with micro-scale channels and chambers. Such microfluidic systems can be used for numerous applications, including reactions, separations, or detection of various compounds. Therefore, due to their potential as microreactors, a particular research focus was noted in exploring various microchannel configurations for on-chip chemical syntheses of materials with tailored properties. Given the significant number of studies in the field, this paper aims to review the recently developed microfluidic devices based on their geometry particularities, starting from a brief presentation of nanoparticle synthesis and mixing within microchannels, further moving to a more detailed discussion of different chip configurations with potential use in nanomaterial fabrication. 相似文献
5.
Karl Sauer Diemair E. Dinslage Kanitz Schwaibold Willy Lindner Haevecker Lehnartz E. Becker W. Schreiber Werner Hofmann Eduard Hofmann Steinbeck H. Süllmann Griebel Rudolf Abderhalden Lars Erlandsen Heyns O. v. Soden C. Steinhoff J. Großfeld Frey-Wyssling W. Sutthoff Bäurle Willy Lindner Ed. Rentz Bandow Gerards K. N. v. Kaulla O. v. Soden Maria Cicconi Pawletta Baars R. Grau Lerche Beckel O. Windhausen Felicitas Rolleri Jesser Karl Boresch R. W. Seuffert K. Müller Schloemer K. Höll Johannes Wolf Brüning Patzsch W. Ludorff 《European Food Research and Technology》1941,81(3):223-288
6.
Dadhichi Paretkar Marleen Kamperman Andreas S. Schneider David Martina Costantino Creton Eduard Arzt 《Materials science & engineering. C, Materials for biological applications》2011,31(6):1152-1159
We developed a dry synthetic adhesive system inspired by gecko feet adhesion that can switch reversibly from adhesion to non-adhesion with applied pressure as external stimulus. Micropatterned polydimethylsiloxane (PDMS) surfaces with pillars of 30 μm length and 10 μm diameter were fabricated using photolithography and moulding. Adhesion properties were determined with a flat probe as a function of preload. For low and moderate applied compressive preloads, measured adhesion was 7.5 times greater than on flat controls whereas for high applied preloads adhesion dropped to very low values. In situ imaging shows that the increased preload caused the pillars to deform by bending and/or buckling and to lose their adhesive contact. The elasticity of PDMS aids the pillar recovery to the upright position upon removal of preload enabling repeatability of the switch. 相似文献
7.
Jan-Bernd Hövener Eduard Y. Chekmenev Kent C. Harris William H. Perman Thao T. Tran Brian D. Ross Pratip Bhattacharya 《Magma (New York, N.Y.)》2009,22(2):123-134
Object Define MR quality assurance procedures for maximal PASADENA hyperpolarization of a biological 13C molecular imaging reagent.
Materials and methods An automated PASADENA polarizer and a parahydrogen generator were installed. 13C enriched hydroxyethyl acrylate, 1-13C, 2,3,3-d3 (HEA), was converted to hyperpolarized hydroxyethyl propionate, 1-13C, 2,3,3-d3 (HEP) and fumaric acid, 1-13C, 2,3-d2 (FUM) to hyperpolarized succinic acid, 1-13C, 2,3-d2 (SUC), by reaction with parahydrogen and norbornadiene rhodium catalyst. Incremental optimization of successive steps in
PASADENA was implemented. MR spectra and in vivo images of hyperpolarized 13C imaging agents were acquired at 1.5 and 4.7 T.
Results Application of quality assurance (QA) criteria resulted in incremental optimization of the individual steps in PASADENA implementation.
Optimal hyperpolarization of HEP of P = 20% was achieved by calibration of the NMR unit of the polarizer (B
0 field strength ± 0.002 mT). Mean hyperpolarization of SUC, P = [15.3 ± 1.9]% (N = 16) in D
2O, and P = [12.8 ± 3.1]% (N = 12) in H
2O, was achieved every 5–8 min (range 13–20%). An in vivo 13C succinate image of a rat was produced.
Conclusion PASADENA spin hyperpolarization of SUC to 15.3% in average was demonstrated (37,400 fold signal enhancement at 4.7 T). The
biological fate of 13C succinate, a normally occurring cellular intermediate, might be monitored with enhanced sensitivity. 相似文献
8.
El Mostapha Aboulhamid Younès Karkouri Eduard Cerny 《Journal of Electronic Testing》1993,4(3):237-253
This article presents a new method to generate test patterns for multiple stuck-at faults in combinational circuits. We assume the presence of all multiple faults of all multiplicities and we do not resort to their explicit enumeration: the target fault is a single component of possibly several multiple faults. New line and gate models are introduced to handle multiple fault effect propagation through the circuits. The method tries to generate test conditions that propagate the effect of the target fault to primary outputs. When these conditions are fulfilled, the input vector is a test for the target fault and it is guaranteed that all multiple faults of all multiplicities containing the target fault as component are also detected. The method uses similar techniques to those in FAN and SOCRATES algorithms to guide the search part of the algorithm, and includes several new heuristics to enhance the performance and fault detection capability. Experiments performed on the ISCAS'85 benchmark circuits show that test sets for multiple faults can be generated with high fault coverage and a reasonable increase in cost over test generation for single stuck-at faults. 相似文献
9.
Herminio Martínez Eva Vidal Eduard Alarcón Alberto Poveda 《Analog Integrated Circuits and Signal Processing》2009,61(3):231-246
Continuous-time filters with automatic tuning loops are nonlinear feedback systems that are potentially unstable. To ensure
stability, particularly if the design of the loop controllers is to be improved, the appropriate linear dynamic modeling of
the tunable filter, including control inputs, should be attained. This work aims to present a general dynamic modeling of
continuous-time analog filters with automatic tuning capability. The general analysis leads to an equivalent small-signal
linearized incremental model, from which transfer functions between output variables and control voltages are obtained. Subsequent
to the analysis, it is possible to design compensated loops with enhanced stability and dynamic performance. By way of example,
the modeling of a particular band-pass CMOS continuous-time analog filter is presented in this paper. Two transfer functions
are derived: the transfer function between the output phase shift and the central frequency control voltage, and that between
the output amplitude and the quality factor control voltage. These functions are required to properly tune the central frequency
and quality factor parameters. This modeling makes it possible to propose an adaptive controller with improved stability and
a possible implementation for such a controller. Finally, experimental results are shown for a CMOS 0.8 μm technology. 相似文献
10.
Daniel Fernández Jordi Madrenas Eduard Alarcón 《Analog Integrated Circuits and Signal Processing》2013,74(1):227-238
In this paper we present an asynchronous finite-state machine digital controller co-integrated with an on-chip non-inverting buck-boost power converter with dynamic signal-tracking capabilities. The mostly-digital controller functionally implements a non-PWM zone-wise control law through asynchronous circuitry, thus exhibiting self-timed minimum latency and ultra low power operation due to gate switching activity. Experimental results on a 0.35 μm CMOS technology demonstrate an efficiency up to 80 % with a switching frequency of 2.86 MHz. 相似文献