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Excessive power supply noise during test can cause overkill. This article discusses two models for supply noise in delay testing and their application to test compaction. The proposed noise models avoid complicated power network analysis, making them much faster than existing power noise analysis tools. can cause performance degradation and  相似文献   
155.
The authors formulate the criteria for drawing dataflow diagrams and describe the placement and routing algorithms used in a system called MONDRIAN. A generalized approach to the question of software diagrams is proposed based on the authors' experience with MONDRIAN and a metasystem approach to the creation of CASE (computer-aided software engineering) environments. A formal approach to the definition of software objects and their graphical representation is given. The use of location constraints as a basis for generalized layout algorithms is discussed  相似文献   
156.
The photoelectric properties of cotton fibers treated with iodine were studied in the fundamental absorption range. The samples exhibit a sublinear illumination-current characteristic and a long-term relaxation of photoconductivity (PC) after UV irradiation (=5 eV) of the iodine-doped fibers. A PC mechanism is proposed which explains both the nonlinear variation of photocurrent with illumination intensity and the PC decay according to a bimolecular recombination law after UV irradiation of the iodine-doped fiber in the fundamental absorption range.  相似文献   
157.
We propose analytic procedures capable of evaluation of the orders of power singularities of magnetic fields at the edge of a composite ferromagnetic wedge bordering with a vacuum. The same procedure is used to study the singularities at the edge of a composite piezoceramic wedge. As a result, we present the plots characterizing the dependences of the order of singularities on the wedge angles of the wedges used to form the analyzed composite wedge and the combination of their physical parameters.  相似文献   
158.
For purposes of optimizing ion-optical systems, analyzer construction, and pump placement in static magnetic mass-spectrometers for isotopic analysis of uranium compounds, a comparative analysis is made and a review is given of methods described in the literature for theoretical estimates of the influence of scattering and reflection of ions on the isotopic sensitivity. Conclusions which make it possible to solve the problem are drawn.  相似文献   
159.
This study tried to investigate, by the power comsumption technique, the influence of the powder's and solvent's properties on wet granulation.

It could be shown that the required amount of granulation liquid decreases when the particle size of the powder to be granulated increases. This relationship is however only true when the particle size distribution of the powder to be granulated is rather narrow.

Powders having the same solubility in different solvents require the same optimal liquid quantity for granulation, but the properties of resulting granules depend on surface tension and wetting properties of the solvent.

When the powder to be granulated contains crystallisation water, the temperature rising in the mixer can be sufficient to liberate this water, which must be taken into account in the optimal granulation liquid requirement.

The effect of a macromolecular binder (PVP, HPMC) has also been studied: the optimal liquid quantity required changes with the kind of binder used and the manufacturing process (binder used in solution or added as dry powder).

It was also shown that in the case of lactose, the optimal quantity of PVP or HPMC can be determined from the power consumption records and from the granules friability studies  相似文献   
160.
The nature of damage produced by low energy Ar+ ion and Ar atom milling in the II–VI semiconductors CdTe, ZnS and ZnSe is studied in detail by conventional and high resolution transmission electron microscopy. It is demonstrated that the damage consists of dense arrays of small dislocation loops near to each milled surface. When ion or atom milling of this type is used for thin specimen preparation prior to microscopy the loop arrays can seriously obscure images and so complicate their interpretation. This problem concerning the presence of artifactual defects can be greatly reduced by the use of reactive I+ ion milling for specimen thinning and, in the case of CdTe, spurious dislocation loop formation can be completely suppressed.  相似文献   
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