Experimental results for end-point positioning of multilink flexible manipulators are considered. This control strategy has been implemented on an experimental test-bed developed in the authors' Laboratory. The ad...
详细信息
Experimental results for end-point positioning of multilink flexible manipulators are considered. This control strategy has been implemented on an experimental test-bed developed in the authors' Laboratory. The advocated approach is based on a two-stage control design. The first stage is an inner-loop nonlinear-based controller corresponding to the rigid body motion of the manipulator. The second stage is an outer control loop based on linear output LQR design. The outer-loop control design results in a nonconvex nonlinear optimization problem. A software package has been developed to solve this problem. The outer-loop controller enhances vibration damping and robustness of the closed-loop dynamics to parameter variations. The measurement utilized for vibration suppression is through an accelerometer attached at the end point of the manipulator.< >
The reliability of copper metallization on silicon-dioxide over single crystalline silicon was studied by capacitance techniques, secondary-ion-mass spectroscopy analysis and Rutherford back scattering. The metallizat...
详细信息
The reliability of copper metallization on silicon-dioxide over single crystalline silicon was studied by capacitance techniques, secondary-ion-mass spectroscopy analysis and Rutherford back scattering. The metallization was either evaporated copper or electroless copper deposited in an alkali-free process. The barrier role of a titanium adhesion layer between the copper and the oxide has also been studied. Bias-thermal stress (BTS) studies of MOS structures were conducted at 150 degrees C, 250 degrees C, 275 degrees C and 300 degrees C. The biased samples were stressed at electric field of 1 MV/cm for a time ranging between 10 minutes for the higher temperatures up to 168 hours at the lower temperatures. The high-frequency capacitance versus voltage (CV) characteristics of the MOS devices change drastically when the copper reaches the Si/SiO/sub 2/ interface. The penetration time of copper through the oxide was characterized as a function of the temperature and was found to increase exponentially with temperature with an activation energy of about 0.85+or-0.2 eV. Without bias only a small amount of copper penetrates the oxide.< >
The advent of decentralized computing and an increasingly important role for information as a resource has prompted the development of a variety of methods and tools for managing the risk exposure of a computer system...
详细信息
A description is given of the authors' experiences in implementing a divide-and-conquer-type parallel algorithm due to J.J. Cuppen (1981) on the Alliant multivector processor. An analysis of the algorithm and its ...
详细信息
A description is given of the authors' experiences in implementing a divide-and-conquer-type parallel algorithm due to J.J. Cuppen (1981) on the Alliant multivector processor. An analysis of the algorithm and its implementation on the Alliant multivector processor are presented. To promote portability of parallel algorithms across various architectures, J.J. Dongarra and D.C. Sorenson (1987) recently developed a tool called sch.DULE. Results obtained with and without sch.DULE are compared.< >
An investigation was conducted of the recognition of difficult CV (consonant-vowel) syllables using PC-based neural network paradigms with LPC coefficients as inputs. The speech corpus consisted of 16 syllables produc...
详细信息
An investigation was conducted of the recognition of difficult CV (consonant-vowel) syllables using PC-based neural network paradigms with LPC coefficients as inputs. The speech corpus consisted of 16 syllables produced by 3 speakers. The input to the neural network was the differences in LPC coefficients sampled at each syllable's time-waveform. A fully connected three-layered back-propagation network was trained by the delta learning rule. With a relatively small number of parameters for each syllable, based on 240 tokens of 16 difficult CV syllables spoken within a sentence context by three speakers, preliminary results for test data indicated that the recognition accuracy is as high as 70.8%.< >
A dual-slope phase meter has been designed and tested to investigate its limitations. The design does not require a time standard; it offers good resolution, relative simplicity, low sensitivity to changes of internal...
详细信息
A dual-slope phase meter has been designed and tested to investigate its limitations. The design does not require a time standard; it offers good resolution, relative simplicity, low sensitivity to changes of internal circuit parameters, and microprocessor compatibility. The idea is based on a single-slope approach demonstrated by W.T. Davis (1986), but several disadvantages of the system have been eliminated. The main problem with the system, relating to the error due to the finite time of sampling, is discussed.< >
暂无评论