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111.
Gonzalez A.F. Bhattacharya M. Kulkarni S. Mazumder P. 《Solid-State Circuits, IEEE Journal of》2001,36(6):924-932
This paper presents a fully integrated implementation of a multivalued-logic signed-digit full adder (SDFA) circuit using a standard 0.6-μm CMOS process. The radix-2 SDFA circuit, based on two-peak negative-differentiaI-resistance (NDR) devices, has been implemented using MOS-NDR, a new prototyping technique for circuits that combine MOS transistors and NDR devices. In MOS-NDR, the folded current-voltage characteristics of NDR devices such as resonant-tunneling diodes (RTDs) are emulated using only nMOS transistors. The SDFA prototype has been fabricated and correct function has been verified. With an area of 123.75 by 38.7 μm2 and a simulated propagation delay of 17 ns, the MOS-NDR prototype is more than 15 times smaller and slightly faster than the equivalent hybrid RTD-CMOS implementation 相似文献
112.
Determining the relative effectiveness of islanding detectionmethods using phase criteria and nondetection zones 总被引:1,自引:0,他引:1
Ropp M.E. Begovic M. Rohatgi A. Kern G.A. Bonn R.H. Sr. Gonzalez S. 《Energy Conversion, IEEE Transaction on》2000,15(3):290-296
Islanding of a utility-interactive photovoltaic (UIPV) system occurs if the UIPV system continues to power a section of the utility system after that section has been disconnected from the utility source. Since islanding creates hazards for personnel and equipment, UIPV systems are required to detect and prevent it. It is desirable to have a simplified method of determining which islanding detection methods (IDMs) are most effective. In this paper, a previously described method for finding the nondetection zones (NDZs) of IDMs is experimentally verified. This method is used to determine the NDZs of several common IDMs. These results indicate that, of the IDMs discussed in this paper: (1) Sandia Frequency Shift (SFS) is most effective; and (2) the worst-case loads are low-power loads that are near resonance at the line frequency and have a large capacitance and small inductance (a high value of the quality factor Q) 相似文献
113.
T. F. Gonzalez 《Algorithmica》2000,28(2):255-267
The on-line multidimensional dictionary problem consists of executing on-line any sequence of the following operations: INSERT(p) , DELETE(p) , and MEM-BER-SHIP(p) , where p is any (ordered) d -tuple (or string with d elements, or points in d -space where the dimensions have been ordered). We introduce a clean structure based on balanced binary search trees, which
we call multidimensional balanced binary search trees, to represent the set of d -tuples. We present algorithms for each of the above operations that take O(d + log n) time, where n is the current number of d -tuples in the set, and each INSERT and DELETE operation requires no more than a constant number of rotations. Our structure
requires dn words to represent the input, plus O(n) pointers and data indicating the first component where pairs of d -tuples differ. This information, which can be easily updated, enables us to test for MEMBERSHIP efficiently. Other operations
that can be performed efficiently in our multidimensional balanced binary search trees are: print in lexicographic order (O(dn) time), find the (lexicographically) smallest or largest d -tuple (O( log n) time), and concatenation (O(d + log n) time). Finding the (lexicographically) k th smallest or largest d -tuple can also be implemented efficiently (O( log n) time), at the expense of adding an integer value at each node.
Received June 13, 1997; revised September 3, 1998. 相似文献
114.
The Guggenheim model of the interphase has been used to study ionic adsorption at electrode interphases from constant ionic strength solutions. Starting with an experimental adsorption isotherm, we deduce the electric equation of state and this equation can help to know what kind of systems respond to the adsorption isotherm. Interphase electrochemical potentials are also obtianed and the stardard state guage is comented. Results can be transferred to understand some trends of ionic adsorption at varying ionic strength solutions. 相似文献
115.
Over the last few decades, vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) have emerged as multifaceted players in not only the pathogenesis, but potential treatment, of numerous diseases. They activate diverse intracellular signaling cascades known to have extensive crosstalk, and have been best studied for their effects in cardiology and cancer biology. Recent work with the two factors indicates that the activity of one growth factor is often directly related to the action of the other. Their respective neuroprotective effects, in particular, raise important questions regarding the treatment of neurodegenerative disorders, including Parkinson's disease. 相似文献
116.
J. Martin-Martinez E. Amat M.B. Gonzalez P. Verheyen R. Rodríguez M. Nafría X. Aymerich E. Simoen 《Microelectronics Reliability》2010,50(9-11):1263-1266
Hot-carrier degradation in pMOS transistors with Si1–xGex implantations in the source and drain areas is analyzed (SiGe S/D). A simulation methodology is developed to translate the effects to circuit simulators. This methodology is applied to study hot-carrier degradation in CMOS inverters designed with SiGe S/D pMOS transistors. The results show that although pMOS transistors with embedded SiGe S/D have a better device performance, these devices are more sensitive to hot-carrier degradation at both the device and circuit levels. 相似文献
117.
L H Molina M Casanova L A Gonzalez M Pinto E Carrasco C Brito 《International Journal of Dairy Technology》2003,56(4):211-214
The genetic variants of κ-casein (κ-CN) A and B were analysed in milk from Holstein–Friesian (HF) and Jersey cows by means of isoelectric focusing (IEF) electrophoresis. Milk samples were obtained in triplicate from pure-breed HF and Jersey cows (three of each) to estimate the protein content, casein and purify κ-CN. The protein and casein contents in the milk from both breeds were statistically different ( P < 0.05). The κ-CN A migrates first with an isoelectric point (pI) of 7.2–7.3 and then B with a pI of 7.5–7.7. Differences in the expression proportion of both variants were detected. 相似文献
118.
Electromagnetic fields close to radiant structures can be measured quickly using an infrared camera. Examples of induced fields by wire antennas over a detection screen at distances shorter than one wavelength are presented. The measured thermograms agree with simulations that take into account heat propagation on the detection screen. 相似文献
119.
Norma Yadira Mendoza Gonzalez Mbark El Morsli Pierre Proulx 《Journal of Thermal Spray Technology》2008,17(4):533-550
In this work a coupled model for the production of nanoparticles in an inductively coupled plasma reactor is proposed. A Lagrangian
approach is used to describe the evaporation of precursor particles and an Eulerian model accounting for particle nucleation,
condensation, and fractal aggregation. The models of the precursor and nanoparticles are coupled with the magneto-hydrodynamic
equations describing the plasma. The purpose of this study is to develop a model for the synthesis of particles in a thermal
plasma reactor, which can be used to optimize industrial reactors. The growth of aggregates is considered by introducing a
power law exponent D
f. Results are compared qualitatively and quantitatively with existing experimental data from plasma reactors at a relatively
large laboratory scale. The results obtained from the model confirm the previously observed importance of the quench strategy
in defining the morphology of the nanoparticles. 相似文献
120.
Antonio Lopez Martin Jose Maria Algueta Miguel Lucia Acosta Jaime Ramírez‐Angulo Ramón Gonzalez Carvajal 《ETRI Journal》2011,33(3):393-400
A systematic approach for the design of two‐stage class AB CMOS unity‐gain buffers is proposed. It is based on the inclusion of a class AB operation to class A Miller amplifier topologies in unity‐gain negative feedback by a simple technique that does not modify quiescent currents, supply requirements, noise performance, or static power. Three design examples are fabricated in a 0.5 µm CMOS process. Measurement results show slew rate improvement factors of approximately 100 for the class AB buffers versus their class A counterparts for the same quiescent power consumption (< 200 µW). 相似文献