Improved coupling technique of ultracompact ring resonators in silicon-on-insulator technology

In order to improve the coupling coefficient between a bus waveguide and a bent waveguide of an ultracompact microring to obtain the critical coupling, a design using a bent bus waveguide with reduced width is provided to maintain a better phase matching and increase the coupling. A full vectorial finite difference model, specifically suited for high index contrast and smaller size waveguides, for example, a waveguide in the silicon-on-insulator (SOI) technology, is developed. As a validation, the straight and bent waveguides are simulated using this model, whose results are compared with the results deduced from the measurement results of the ultracompact ring resonators in SOI technology. Also, the model solver is performed to simulate the design, and an experiment is implemented to testify the design.     

A human motor behavior model for distal pointing tasks

Models of human motor behavior are well known as an aid in the design of user interfaces (UIs). Most current models apply primarily to desktop interaction, but with the development of non-desktop UIs, new types of motor behaviors need to be modeled. Distal pointing—pointing directly at a target that is remotely situated with respect to the input device—is such a motor behavior. A model of distal pointing would be particularly useful in the comparison of different interaction techniques, because the performance of such techniques is highly dependent on user strategy, making controlled studies difficult to perform. Inspired by Fitts’ law, we studied four possible models and concluded that movement time for a distal pointing task is best described as a function of the angular amplitude of movement and the angular size of the target. Contrary to Fitts’ law, our model shows that the angular size has a much larger effect on movement time than the angular amplitude and that the growth in the difficulty of the tasks is quadratic, rather than linear. We estimated the model's parameters experimentally with a correlation coefficient of 96%.     

Efficient global optimization for high-dimensional constrained problems by using the Kriging models combined with the partial least squares method

In many engineering optimization problems, the number of function evaluations is often very limited because of the computational cost to run one high-fidelity numerical simulation. Using a classic optimization algorithm, such as a derivative-based algorithm or an evolutionary algorithm, directly on a computational model is not suitable in this case. A common approach to addressing this challenge is to use black-box surrogate modelling techniques. The most popular surrogate-based optimization algorithm is the efficient global optimization (EGO) algorithm, which is an iterative sampling algorithm that adds one (or many) point(s) per iteration. This algorithm is often based on an infill sampling criterion, called expected improvement, which represents a trade-off between promising and uncertain areas. Many studies have shown the efficiency of EGO, particularly when the number of input variables is relatively low. However, its performance on high-dimensional problems is still poor since the Kriging models used are time-consuming to build. To deal with this issue, this article introduces a surrogate-based optimization method that is suited to high-dimensional problems. The method first uses the ‘locating the regional extreme’ criterion, which incorporates minimizing the surrogate model while also maximizing the expected improvement criterion. Then, it replaces the Kriging models by the KPLS(+K) models (Kriging combined with the partial least squares method), which are more suitable for high-dimensional problems. Finally, the proposed approach is validated by a comparison with alternative methods existing in the literature on some analytical functions and on 12-dimensional and 50-dimensional instances of the benchmark automotive problem ‘MOPTA08’.     

A family of inequalities valid for the robust single machine scheduling polyhedron

We consider the problem of sequencing a set of jobs in a single machine to minimize the maximum of the total weighted completion time of the jobs over a number of scenarios, each corresponding to a set of job processing times. We give a large family of inequalities that are valid for the convex hull of the set of feasible schedules. We then present computational experience in which some of the inequalities are added to the original formulation. We demonstrate through the computational results that their addition to the formulation can substantially improve, among other things, the time required to solve difficult instances of the problem through branch-and-cut.     

Automated cement plant quality control

Increasing production and quality demands in the cement industry have resulted in the need for improvement in the speed and accuracy of quality-control results. This need has been addressed many technological advances in quality-control automation in recent years. Two distinct methods of sampling and analysis, in-situ and extractive, have gradually developed. In-situ analysis occurs in the field at the process equipment, with the results transmitted through a computer control system. This article discusses the characteristics and differences in analyzer and control technologies that utilize the two different methods of obtaining a result.     

Some unresolved challenges facing psychology's entrance into the health care field.

Psychology has recently attempted to broaden service, research, and training opportunities. However, major differences between psychology and medicine over paradigms, training approaches, and organizational and professional practice issues may impede psychology's growth in the health science field. The hospital setting for physicians and for university and community training environments for psychologists foster the development of different analytic abilities and attitudes regarding disciplinary primacy and approaches to patient care. As such, total medical authority over all health-related professions is sought. This medical dominance is inimical to the emergence of psychology as an independent health-related discipline. These differences are further magnified at a professional level, as psychology expands the scope of its practice and threatens the economic and organizational control that medicine exerts over health care. Concern is expressed over the ability of psychology to establish itself as a major force in a field that is structurally dominated by the medical profession, which would probably resist any change that is not in its own best interest. (42 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Self-description as a predictor of rate of promotion of junior Foreign Service Officers.

An experiment to determine relationship between responses to an attitude, interests, and background questionnaire, and rate of promotion of Foreign Service Officers. Ss, who had completed an 89-item questionnaire May 1958, were divided first into an experimental group (N = 20) and a cross-validation group (N = 49), and then into high and low groups on the basis of promotions as of January 1961. Of the scales developed from previous studies, only the Social Isolation one proved to be useful. However, 2 new elements, Optimism and Self-Potency, proved to be effective measures for predicting the criterion. A correlation of .60 was found between the combined scores on these 3 elements and speed of promotion for the cross-validation group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Self-description as a predictor of success or failure in foreign service clerical jobs.

In attempting to predict success or failure in various clerical jobs in the Foreign Service, how useful are responses to questions about attitudes, interests, activities, and family background? From Spring 1954 to December 1956 1183 questionnaires were collected from clerical employees. For each of these employees numerical ratings, length of service and, for those who had terminated, reasons for leaving were determined. "Seven behavioral elements which related to ways of responding to authority, ways for dealing with people, and level of use of intellect appeared to be suggested by the data. It seems likely that the effectiveness of the questionnaire can be improved by redesigning it specifically to measure the behavioral style and capability elements which have emerged from this study." From Psyc Abstracts 36:02:2LD16W. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Low-frequency noise in single–poly bipolar transistors at low base current density

This paper deals with the low-frequency noise of single–poly bipolar transistors (SBJT) biased at low base current density. From Gummel plots and low-frequency noise measurements performed on many SBJTs made using the same process, it is clearly demonstrated that the low-frequency noise is related to generation–recombination mechanisms (GR) that occur at the periphery of the emitter–base space charge region. A model which takes into account both the diffusion noise and the GR noise is proposed. A comparison with some measurements performed on another BiCMOS technology and with some results of the literature validates this analysis.     

Quasi hermetic packaging for new generation of spaceborn microwave equipment

This paper presents the introduction of the quasi hermetic encapsulation of microwave hybrids for space application through different approaches evaluated at Thales Alenia Space – France. Thanks to the improvement for many years of microwave organic materials, it is now realistic to propose advanced packaging solutions like the chip on board approach with glob top encapsulation of active devices directly bonded on printed circuit boards for space applications. To validate this packaging approach, very significant reliability test-plans have been proposed and performed on the different technological processes and materials in agreement with standard space quality requirements. Results will be presented and a discussion on the nature of the stresses applied during the tests will be proposed.