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1.
Journal of Signal Processing Systems - With the latest development of automation technology, object detection technology has received more and more research attention. Automated object detection...  相似文献   
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This paper analyses the performance of the anaerobic selector (A/O process) in a full-scale activated sludge process receiving mostly industrial sewage discharge (> 60%) in Singapore. In addition to the sludge settleability, enhanced biological phosphorus removal (EBPR) was studied. The sludge volume index (SVI) reduced from 200 to 80 ml g(-1) and foaming was suppressed significantly, indicating the effectiveness of the anaerobic selector in improving sludge settleability. The phosphorus removal efficiency was 66%, and 7.5 mg HAc-COD was consumed per mg PO4(3-) -P removed. In the anaerobic compartment, 31% of the SCOD and 73% of the acetic acid in the settled sewage were removed with PO4(3-) -P release of 14.1 mg PO4(3-)-P l(-1). The linear correlation between PO4(3-) -P release in the anaerobic compartment and PO4(3-) -P uptake in the aerobic compartment indicates that there is about 0.8 mg PO4(3-) -P release in the anaerobic compartment per mg PO34(3-) -P uptake in the aerobic compartment. The fates of volatile fatty acids (VFAs) and its short chain acids (SCAs) in the process were studied and discussed.  相似文献   
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Ho  Y. S.  Chiu  C. H.  Tseng  T. M.  Chiu  W. T. 《Scientometrics》2003,57(3):369-376
Honour Index (HoI), a method to evaluate research performance within different research fields, was derived from the impact factor (IF). It can be used to rate and compare different categories of journals. HoI was used in this study to determine the scientific productivity of stem cell research in the Asian Four Dragons (Hong Kong, Singapore, South Korea and Taiwan) from 1981 to 2001. The methodology applied in this study represents a synthesis of universal indicator studies and bibliometric analyses of subfields at the micro-level. We discuss several comparisons, and conclude the developmental trend in stem cell research for two decades. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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Polyaryloxydiphenylsilanes were prepared from phosphorus‐containing diols and diphenydichlorolsilane through solution polymerization. With a stoichiometric imbalance in feed monomers, the resulting polymers exhibited moderate melting points and good processing properties. The polymers prepared showed initial decomposition temperatures above 340 °C, excellent thermal stability, high char yields at 850 °C and very high limited oxygen index values of 56–59. The polymers' char yields and their (P + Si) contents showed linear relationships. © 2003 Society of Chemical Industry  相似文献   
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Dynamic cardiomyoplasty (DCM) involves the electrical stimulation of a pedicled latissimus dorsi muscle flap wrapped around the falling ventricle as a means of cardiac assist. To further elucidate a potential neurohumoral mechanism for improvement of cardiac output after myoplasty, we evaluated the hemodynamic effects of in situ stimulation of the latissimus dorsi muscle (in the absence of cardiomyoplasty). In seven mongrel dogs, a nerve cuff electrode (Medtronic 6901) was placed around the left thoracodorsal nerve (TDN). This was attached to a pulse generator (Medtronic, Itrel 7420), delivering a 4.0 volt, 0.19 second on, 0.81 second off, 33 Hz, 210 microsecond pulse width, cyclic bursts similar to that used in DCM. Stroke volume index (SVI) and other hemodynamic parameters as well as plasma norepinephrine (NE) levels were measured at five stages: baseline, stimulator on at 0, 2, and 5 minutes, and stimulator off at 30 minutes after. The animals were then subjected to 4 weeks of rapid pacing at 240 beats/min (Medtronic 8329) to induce heart failure, and as the rapid pacing was discontinued, measurements were repeated as above. After rapid pacing, cardiac function was significantly depressed, and NE was elevated (133 +/- 69 versus 500 +/- 353 pg/mL, p < 0.05). In the normal hearts, TDN stimulation increased SVI, heart rate, systemic pressure, and NE levels. In heart failure, however, no significant changes in cardiac function and NE levels were noted. In conclusion, our data indicate that in the normal hearts, afferent impulses from TDN stimulation alone may augment cardiac function by means of a neurohumoral effect that is not seen in severe heart failure. The implications of these findings in DCM are discussed.  相似文献   
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In this paper we propose a novel built-in self-test (BIST) design for embedded SRAM cores. Our contribution includes a compact and efficient BIST circuit with diagnosis support and an automatic diagnostic system. The diagnosis module of our BIST circuit can capture the error syndromes as well as fault locations for the purposes of repair and fault/failure analysis. In addition, our design provides programmability for custom March algorithms with lower hardware cost. The combination of the on-line programming mode and diagnostic system dramatically reduces the effort in design debugging and yield enhancement. We have designed and implemented test chips with our BIST design. Experimental results show that the area overhead of the proposed BIST design is only 2.4% for a 128 KB SRAM, and 0.65% for a 2 MB one.  相似文献   
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Oxygen injection has been proposed and experimentally demonstrated as an effective control measure for limiting the rate of heat release and altering the rate of polymerization in emulsion processes. A detailed mathematical model has been previously developed to describe the system behavior with and without oxygen injection. A simple lab scale apparatus was constructed and run extensively. Only trace quantities of oxygen are needed to inhibit the reaction completely. The facile response makes this method attractive for fast temperature control. However, because of the rapid penetration of dissolved oxygen into the polymer particles, growing radical chains are terminated prematurely, lowering product molecular weights. To minimize this detrimental effect, pulsed oxygen control is used and extensive experimental work was performed to determine the effects of controller set points on molecular weight. Moderate oxygen flows and moderate set point temperatures are found to give the optimal response without significant lowering of the final molecular weight. Injected quantities agree well with the order-of-magnitude sparging calculations needed to completely stop initiation. However, complete agreement between model simulations and experimental results was not reached due to an unmeasured loss of monomer from the reactor. Chain transfer to monomer is found to be important in modeling the polymer molecular weight. It has, however, a negligible effect on the reaction rate.  相似文献   
10.
A novel traveling-wave electrode utilizing capacitively loaded T-rail elements was developed for low-voltage high-speed substrate-removed GaAs/AlGaAs electrooptic modulators. Electrodes with varying dimensions were fabricated and characterized. Electrode phase velocity, characteristic impedance, loss coefficient, and capacitive loading were extracted from the measured s-parameters up to 40 GHz. Electrode was also simulated using a finite-element solver. The measured and calculated electrode capacitance values were found to be in excellent agreement, showing that the electrode can be precisely designed. Approaches were outlined to provide a group velocity-matched very high-speed modulator electrode suitable for a low drive-voltage substrate-removed GaAs/AlGaAs electro-optic modulator  相似文献   
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