At Philips Communications Industry (PKI), we develop embedded telecommunication-infrastructure systems. Because we must deliver each product in site-specific configurations - of which there are many - and because the ...
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At Philips Communications Industry (PKI), we develop embedded telecommunication-infrastructure systems. Because we must deliver each product in site-specific configurations - of which there are many - and because the development of such systems is a major investment, we must create a product family rather than a single produce. We organize system construction according to three design dimensions covered by the system architecture: structure, aspects, and behavior. Of the three dimensions, we consider structure to be the most important. In this dimension, reducing complexity is our main concern. We thus organize system functionality into four layers, or subsystems. These subsystems are composed of software modules - 'building blocks' - which are the basic software entities in the system architecture. The Building-Block Method is an architectural method. It does not prescribe the precise method you should use to develop the building blocks. You can use different methods within one system according to the specific requirements for each building block. You fan also use formal or informal specifications for building blocks, depending upon your application domain.
We describe a method for estimating a probability density function when some of the sufficient statistics are known. The general form of the PDF is within the exponential family and is known as the exponentially embed...
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We describe a method for estimating a probability density function when some of the sufficient statistics are known. The general form of the PDF is within the exponential family and is known as the exponentially embedded family. Using the proposed estimator new approaches to choosing features from a set of possible features become available, with the error metric being the Kullback-Liebler distance. Applications to subset selection in the context of multipath estimation as well as linear regression for machine learning are used to illustrate the practical utility of the method.
The interlayer van der Pauw (VDP) resistor alignment bridge combines the sheet resistor and registration-sensitive bridge into one unified structure. As a result of symmetry, it does not require the width corrections ...
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The interlayer van der Pauw (VDP) resistor alignment bridge combines the sheet resistor and registration-sensitive bridge into one unified structure. As a result of symmetry, it does not require the width corrections resulting from image exposure and etch variations typical of linear resistor structures. It uses minimum area and pad count and provides orthogonal registration measurements. Bridges designed for 1.5- mu m feature size with body dimensions of 18 and 21 mu m and a tap length to width ratio of 0.5 show a sensitivity of 34-38 mV/ mu m at 10 mA. Registration errors of 0.2 mu m have been measured with an error of less than 10%. A good statistical correlation has been obtained between drawn and measured registration offsets. The correlation between the VDP bridge and the optical vernier is within +or-2% using a vernier spacing of 0.125 mu m. These results clearly indicate that the VDP bridge has the potential to provide accurate measurements of photo mask registration with the precision required for very large scale integration (VLSI) processing. The application of the VDP resistor bridge for interlayer registration using standard production procedures is described. Measurement precision and accuracy are discussed along with some fundamental bridge-design considerations.< >
The authors describe a 14-ns 1-Mb CMOS SRAM (static random-access memory) with both 1M word*1-b and 256 K word*4-b organizations. The desired organization is selected by forcing the state of an external pin. The fast ...
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The authors describe a 14-ns 1-Mb CMOS SRAM (static random-access memory) with both 1M word*1-b and 256 K word*4-b organizations. The desired organization is selected by forcing the state of an external pin. The fast access time is achieved by the use of a shorter divided-word-line (DWL) structure, a highly sensitive sense amplifier, a gate-controlled data-bus driver, and a dual-level precharging technique. The 0.7- mu m double-aluminum and triple-polysilicon process technology with trench isolation offers a memory cell size of 41.6 mu m/sup 2/ and a chip size of 86.6 mm/sup 2/. The variable bit-organization function reduces the testing time while keeping the measurement accuracy of the access times.< >
We presented a calculation of the total and partial decay widths of vibrational predissociation (VP) of the HeI2 molecule for low initial vibrational excitations from the lowest van der Waals (vdW) state with total an...
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We presented a calculation of the total and partial decay widths of vibrational predissociation (VP) of the HeI2 molecule for low initial vibrational excitations from the lowest van der Waals (vdW) state with total angular momentum J = 0. A time-dependent golden rule wave-packet method was employed in our numerical calculations for the decay widths. The computed total decay widths, lifetimes, and rates of VP are in fairly good agreement with those extrapolated from the experimental data available. Predicted total decay widths as a function of initial vibrational levels exhibit a highly nonlinear behavior. These results demonstrate that a quantum mechanical decay mode for low vibrational excitation remains as well. The total propagation time needed in the time-dependent golden rule wave-packet calculations is much shorter than is the lifetime of the predissociation of HeI2. It is shown that the final-state interaction between the fragments is important for determining the final rotational-state distribution (partial decay width). We find that the major peak position in the final rotational-state distribution shifts to lower rotational energy levels with increase of the initial vibrational quantum number, which is evidently different from that for higher vibrational levels. This fact can be clearly explained by the dependence of the amount of kinetic energy released to the product degrees of freedom on the initial vibrational state. (C) 1997 John Wiley a Sons, Inc.
As EDF is experiencing increasing difficulties to develop its transmission network, the time may have come to reconsider the projects selection method. In this paper, we point out that the currently used method essent...
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As EDF is experiencing increasing difficulties to develop its transmission network, the time may have come to reconsider the projects selection method. In this paper, we point out that the currently used method essentially relies on a classical discounted balance criterion. We then present a new method taking into account the impact of a project on the environment, by considering an environmental risk which may jeopardize the project's success. This method helps to evaluate the probability that each possible route of each project will be carried through. A simple probability computation then allows us to derive a global comparison of the eligible projects on the basis of an expected discounted balance criterion. Experiments now in progress will help to decide upon this method's efficiency in the context of an operational use.
Metallographic investigation of the discs used in tests to simulate gear tooth contact has revealed the occurrence of several microstructural features that are present only in fatigued specimens: e. g. dark etching re...
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Metallographic investigation of the discs used in tests to simulate gear tooth contact has revealed the occurrence of several microstructural features that are present only in fatigued specimens: e. g. dark etching regions ( DER) and white etching bands ( WEB). In addition, a new type of microstructural constituent has been observed close to the surface, below asperities. This feature is referred to as the plastic deformation region ( PDR). For the first time the hardness of these fatigue-induced phases was accurately determined by the nanoindentation technique. It has been found that DER initiates at the prior austenite grain boundaries. Fatigue cracks initiate and propagate preferentially at the boundaries of PDR and ultimately lead to the formation of micropitting. (c) 2005 Springer Science + Business Media, Inc.
The first part of this paper is a description of the design of low-pass, bandpass, high-pass, and notched filter difference equations using Z-transform techniques. The difference equation coefficient word lengths are ...
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The first part of this paper is a description of the design of low-pass, bandpass, high-pass, and notched filter difference equations using Z-transform techniques. The difference equation coefficient word lengths are significantly reduced by using a set of second-order difference equations. These equations have a form that minimizes computation. The second part of the paper contains applications of these filters to the processing of electrocardiograms (ECG). The filters are included as subroutines in a program that also includes an adaptive muscle-tremor filter, an "optimum" ECG estimator, and optimum estimators for the arrival time of various parts of the ECG waveform. Clinical results are presented.
Theoretical expressions for the noise figure F of FET mixers with HF feedback from output to input are compared with experimental data. Good agreement between theory and experiment is obtained. A noticeable improvemen...
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Theoretical expressions for the noise figure F of FET mixers with HF feedback from output to input are compared with experimental data. Good agreement between theory and experiment is obtained. A noticeable improvement in the noise figure of the mixer is possible with this type of feedback.
Carlin and Amstutz's observation that published design methods for Chebyshev impedance-matching networks do not always result in optimum impedance-matching networks, when the total number of reactive elements are ...
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Carlin and Amstutz's observation that published design methods for Chebyshev impedance-matching networks do not always result in optimum impedance-matching networks, when the total number of reactive elements are used as a basis for comparison, is confirmed and explained. Fano's method is used to obtain graphs illustrating the impedance-matching properties of fifth-order Chebyshev filters with the real zero of the reflection coefficient shifted to the right half plane. The information is useful for the solution of certain nondegenerate impedance-matching problems.
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