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991.
It is shown that an N point type I odd discrete cosine transform can be reformulated as a (2N-1) point DFT of a real-symmetric sequence efficiently computed by the real-symmetric PFA-FFT. Using simple index mappings, the type II and III ODCTs are efficiently computed from the ODCT-1 of the same length. The ODCT-IV are then computed from ODCT-II or III using simple recurrence formulas.<> 相似文献
992.
In recent years, the use of software engineering tools for the process industry has increased substantially, accelerating research and development work. However, such tools are essentially limited in their connectivity to other systems and applications. It's therefore challenging to integrate the diverse, components developed using these tools so that they can seamlessly communicate locally and remotely. Accomplishing this integration is nonetheless essential, particularly as process control applications grow larger and more complex. We propose an open, nonproprietary, plug-and-play system (ONPS) for real-time process monitoring and control. Based on the object linking and embedding for process control (OPC) standard, ONPS provides a standard method for individual process monitoring and process control software to interact and share data. 相似文献
993.
994.
Tzou-Chi Huang Hui-Yin Fu Chi-Tang Ho Di Tan Yu-Ting Huang Min-Hsiung Pan 《Food chemistry》2007,103(2):434-443
The compositions of essential oils from leaves of two Cinnamomum osmophloeum clones (A and B) commercially cultivated by Taiwan Cinnamon Biotech Co. Ltd., in Taiwan were investigated. GC and GC–MS analyses showed that Cinnamomum osmophloeum clones A and B contain trans-cinnamaldehyde (91.15%) and cinnamyl acetate (46.39%), respectively, as the major component. This study demonstrated that cinnamaldehyde was able to induce apoptosis in a concentration-dependent manner. Cinnamaldehyde-induced cell death was characterized with changes in nuclear morphology, DNA fragmentation, and cell morphology. Furthermore, treatment with cinnamaldehyde caused a rapid loss of mitochondrial transmembrane potential, stimulation of reactive oxygen species (ROS) production, release of mitochondrial cytochrome c into cytosol, and subsequent induction of procaspase-9 and procaspase-3 processing. Taken together, these results suggest that ROS production and depletion of the glutathione that committed to cinnamaldehyde-induced apoptosis in K562 cells. 相似文献
995.
An alternative, rapid, and reproducible method of analysis for perchlorate in selected food products (fruit and vegetable juice, milk, and bottled water) was developed and validated. Improvements over previous methods were achieved by the use of a rugged and inexpensive C18 column, a multi-mode OASIS HLB solid-phase extraction cartridge for sample clean-up, and acetic acid for pH adjustment and protein precipitation. The hydrophobicity of the perchlorate anion gives it good retention and separation characteristics on C18 chromatographic columns. The C18 column allowed for the use of 90% of acetonitrile at a low flow rate (0.3 ml min(-1)), without splitting, and could also be regenerated with organic solvents, unlike an ion-exchange column. Perchlorate levels in selected commercial food samples were: <1.0-2.1 ng g(-1) (fruit and vegetable juices, reported here for the first time), <1.0-5.0 ng g(-1) (milk), and <1.0 ng g(-1) (bottled water). 相似文献
996.
997.
Rea M. McRobbie D. Elhawary H. Zion Tsz Ho Tse Lamperth M. Young I. 《Mechatronics, IEEE/ASME Transactions on》2008,13(3):379-382
Real-time processing of MRIs is reported as a method of 3D tracking of mechanical devices within the field of view using passive microcoil fiducials. The specific implementation described makes use of two scan planes for full 3D tracking of a 5-DOF manipulator arm used for prostate biopsy under image guidance. Real-time tracking was observed with a maximum update rate of 0.42 frames per second for a maximum probe velocity of 10 mm/s. The localization of fiducials had a mean error of 0.36 (plusmn0.17) mm (p < 0.02), leading to a mean error in the needle tip position of 2.6 (plusmn0.3) mm (p < 0.05). 相似文献
998.
C. H. Wu Y. S. Wong W. H. Ip Henry C. W. Lau C. K. M. Lee G. T. S. Ho 《The International Journal of Advanced Manufacturing Technology》2009,41(3-4):287-300
The hard disk drive is a reliable and relatively cheap mass storage device used in every computer nowadays. In this study, one major issue affecting the product quality of the fixture inside a hard disk drive is the surface contamination of the arm finger of actuator (AFA). For economical exploitation, a primary concern is to generate a model for optimizing the process parameter settings necessary to sustain the desired cleanliness level in an ultrasonic cleaning process. Two approaches were employed to identify critical process parameters, followed by the determination of the optimal parameter settings. The former approach was a statistical design of experiments (DOE) for developing regression equations for predicting the cleanliness level and finding out the dependence of each parameter and outcome. The latter approach was in using an artificial neural network (ANN) for building prediction models. A comparative study showed that both approaches have advantages over other methods. The results obtained show a reduction in contamination of the AFA; hence it provides an aid in the improvement of product quality. 相似文献
999.
Ki Hyuk Kim Hoi Ju Chung Sung Ho Yoon Sung Woo Hwang Jinwoo Park Soo-Won Kim Joongho Choi Ahn D. 《Components and Packaging Technologies, IEEE Transactions on》2000,23(1):183-189
We present a systematic analysis technique of complementary metal-oxide-semiconductor (CMOS) radio-frequency (RF) integrated circuits (ICs). A full simulation program with integrated circuit emphasis (SPICE) simulation of the whole chip including the package and the die, with the parameters extracted from purely software analysis, has been performed. It is shown that the RF impedance matching without S-parameter based techniques is possible and the measured results agree well with our SPICE-only software based technique 相似文献
1000.
The tandem of adaptive filters is common in practice. An example is the tandem of echo cancellers in telecommunication networks. This paper analyzes the convergence characteristics and tracking behavior of two adaptive filters in tandem, together with a comparison of its performance with a single adaptive filter. The adaptive algorithm considered is the LMS and the analysis is on mean-square. The coefficient errors correspond to noise, lag bias and lag variance are examined separately The theoretical results are corroborated with simulations. The study shows that the tandem of two adaptive filters decreases the convergence speed compared to a single adaptive filter. In addition, in steady state and when the step-size is small tandeming increases the coefficient variance due to noise by a factor of 2.5, the coefficient variance due to tracking lag by a factor of 1.5, but decreases the mean-square coefficient bias due to lag by a factor of 2 相似文献