Determination of temperature change inside IC packages during laser ablation of molding compound

In addition to chemical jet etch method, decapsulation performances of electronic packages for failure analysis are virtually enhanced using lasers. Nevertheless circuits inside package could be subjected to a local thermal elevation during the package ablation process. In this paper, we introduce an innovative technique to measure the thermal behavior of an encapsulated system in situ and in real time during laser decapsulation. Measurements of the heat elevation during ablation process in the three regions of interest for failure analysis are discussed: over IC, bonding and lead-frame.     

General and self-consistent method for the calibration of polarization modulators, polarimeters, and mueller-matrix ellipsometers

Calibration of polarization-state generators (PSG's), polarimeters, and Mueller-matrix ellipsometers (MME's) is an important factor in the practical use of these instruments. A new general procedure, the eigenvalue calibration method (ECM), is presented. It can calibrate any complete MME consisting of a PSG and a polarimeter that generate and measure, respectively, all the states of polarization of light. In the ECM, the PSG and the polarimeter are described by two 4 x 4 matrices W and A, and their 32 coefficients are determined from three or four measurements performed on reference samples. Those references are smooth isotropic samples and perfect linear polarizers. Their optical characteristics are unambiguously determined during the calibration from the eigenvalues of the measured matrices. The ECM does not require accurate alignment of the various optical elements and does not involve any first-order approximation. The ECM also displays an efficient error control capability that can be used to improve the MME behavior. The ECM is illustrated by an experimental calibration, at two wavelengths (458 and 633 nm), of a MME consisting of a coupled phase modulator associated with a prism division-of-amplitude polarimeter.     

Employment test validation for minority and nonminority clerks with work sample criteria.

10 tests of intellectual ability and perceptual speed and accuracy were validated against specially developed clerical work samples of telephone company employees, using a newly hired sample of 143 Blacks, 74 Spanish-surnamed, and 195 Whites. Most validity coefficients were statistically significant, and in only 2 out of 36 comparisons were ethnic sample validity coefficients significantly different. A combination of 4 tests was significantly predictive of clerical proficiency for each ethnic sample and for the total combined sample. Comparisons of ethnic sample regression equations indicated that the slopes were essentially the same but that the intercepts differed significantly. The total sample regression equation did not underpredict prospective proficiency levels for minority clerks. A composite predictor found to be appropriate for minority and nonminority applicants for clerical jobs is recommended for employment office use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of a method for direct quantification of cytomegalovirus antigenemia by flow cytometry

Cytomegalovirus (CMV) antigenemia was directly detected in polymorphonuclear leukocytes (PMNLs) from transplant recipients by using flow cytometry (FC). Two fixation and permeabilization methods and seven anti-CMV monoclonal antibodies (MAbs) were evaluated. 1C3, SL20, and NEA-9221 MAbs were more efficacious. The antigenemia detection threshold of FC was 0.05% positive PMNLs, and percentages correlated well with DNA viral load and the appearance of clinical symptoms.     

Power and temperature control on a 90-nm Itanium family processor

This paper describes the embedded feedback and control system on a 90-nm Itanium family processor, code-named Montecito, that maximizes performance while staying within a target power and temperature (PT) envelope. This system, referred to as Foxton Technology (FT), utilizes on-chip sensors and an embedded microcontroller to measure PT and modulate both voltage and frequency (VF) to optimize performance while meeting PT constraints. Changing both VF takes advantage of the cubic relationship of P/spl prop/CV/sup 2/F. We present measured results that show a 31% reduction in power for only a 10% drop in frequency. Montecito is able to implement FT using only 0.5% of the die area and 0.5% of the die power.     

Direct catalytic conversion of methane

Processes are being developed for the direct catalytic oxidative conversion of methane to higher hydrocarbons and oxygenates. The role of the catalyst in generating methyl radicals is established, and subsequent gas-phase reactions are well understood. However, the role of several catalyst surface species remains a subject of interest. Application of present process technology using the most promising catalysts shows that direct methane conversion is not yet competitive with conventional processes. Increased yields of desirable products using new process configurations are required to obtain an economically viable process.     

Activation of cysteine proteases in cowpea plants during the hypersensitive response--a form of programmed cell death

The matrix metalloproteinases appear to play a key role in mammary tissue remodeling during involution. By immunoprecipitation and immunoblot using antibodies against 60K gelatinase which appears during involution a 90K polypeptide has been identified as its inactive proenzyme in the early involuting rat mammary gland. 90K polypeptide was isolated from the second day involuting rat mammary gland by immunoaffinity chromatography. On proteolytic digestion, the inactive 90K polypeptide was converted to active gelatinase. Primary cultures of mammary epithelial cells secreted the 90K polypeptide. These results indicated that the 60K inducible MMP involved in mammary gland involution and remodeling is produced as a 90K proenzyme which is activated by proteolysis in the extracellular sites.     

Viscosities of aluminum-rich Al−Cu liquid alloys

Viscosity data for Al−Cu liquid alloys in the ranges of 0≤C _L≤33.1 wt pct Cu and 1173≤T ≤973 K are reviewed. It was found that Andrade's equation can be used to represent the variation of viscosity with temperature for a given composition, but that each of the two parameters in Andrade's equation shows no systematic variation with composition of the liquid-alloys. Consequently, arithmetic averages of the parameters were used and assumed to apply to all compositions in the range 0≤C _L ≤33.1 wt pct Cu. Such a procedure implies that the viscosity happens to vary with composition solely because the specific volume varies with composition. In order to establish the predictability of extrapolating such simple behavior, a more complex model was considered. The latter model was recently presented by Kucharski and relates viscosity to the structure and thermodynamics of liquid alloys. Viscosities obtained by interpolating Andrade's equation and Kucharski's model compare closely; furthermore, values obtained by extrapolations to lower temperatures also compare favorably. Finally the simpler model was used to calculate the viscosity of the interdendritic liquid during solidification.     

Numerically efficient solution of dense linear system of equationsarising in a class of electromagnetic scattering problems

In this paper we present an efficient technique for solving a dense complex-symmetric linear system of equations arising in the method of moments (MoM) formulation. To illustrate the application of the method, we consider a finite array of scatterers, which gives rise to a large number of unknowns. The solution procedure utilizes preconditioned transpose-free QMR (PTFQMR) iterations and computes the matrix-vector products by employing a compressed impedance matrix. The compression is achieved by reduced-rank representation of the off-diagonal blocks, based on a partial-QR decomposition, which is followed by an iterative refinement. Both the preconditioning and the compression steps take advantage of the block structure of the matrix. The convergence of the iterative procedure is investigated and the performance of the proposed algorithm is compared to that achieved by other schemes. The effectiveness of the preconditioner and the degree of matrix compression are quantified. Finite arrays of variable shape and sizes are considered, and it is demonstrated that the ability to solve large problems using this technique enables one to evaluate the edge effects in the finite array. Such array is basically flat and periodic, but the algorithm is still efficient when variation with strict periodicity or flatness exists     

Global managemenT : A new challenge for oil companies

The oil industry went global well before the word became fashionable. Decades ago, the majors succeeded in integrating their activities so that they achieved almost total mastery over their environment. The changes of the past 20 years, in particular, the nationalizations of the early 1970s imposed new challenges on large oil companies. They now face the complexity of a more competitive environment that they no longer control. The response of many companies has been to redesign their organizations so as to reduce the layers of command. This paper goes further, suggesting a model of organization which favours lateral relations and increases the input of country affiliates in the strategic planning process.