Some basics on tolerances

In this note we deal with sensitivity analysis of combinatorial optimization problems and its fundamental term, the tolerance. For three classes of objective functions (?, ?, MAX) we prove some basic properties on upper and lower tolerances. We show that the upper tolerance of an element is well defined, how to compute the upper tolerance of an element, and give equivalent formulations when the upper tolerance is +? or > 0. Analogous results are proven for the lower tolerance and some results on the relationship between lower and upper tolerances are given.

Proposal for a contents design of a graphic engineering lecture

In this project the subject of Industrial Design from the bachelor’s degree in Industrial Technologies and Economic Analysis of the ETSEIB is reviewed considering the contents and the teaching and evaluating methods. To acquire a great level and teach the subject with great quality, this project has been developed in order to grant that some of the best methods are used to teach and evaluate the students. The contents have also been reviewed to certify that a similar structure of contents is being followed the same way as some of the more relevant engineering schools. As this subject is part of the bachelor’s degree in Industrial Technologies and Economic Analysis, some of the subjects of the bachelor’s degree in Industrial Technologies, which is another degree from the ETSEIB, are used to compare and conclude the methods that could be used to benefit the subject. This has been done since these subjects have been used as a background to develop the contents and the organization of the Industrial Design subject. Research on some of the most relevant engineering schools in the world and in similar subjects such as Graphical Expression or Computer Aided Design has been done. This has determined the differences between the relevant and prestigious schools and the subjects of Graphical Expression or CAD. Once these different methods have been identified, they are considered to be applied to the organization of the subject, as a proposal, in order to enhance its quality and its reputation. To define which universities are better and more adequate for this project, some crucial facts have been used to reduce the research to a more specific group of engineering schools. The idea behind this project is to be able to clarify and help achieving a greater quality in the subject by reviewing some of the most relevant industrial design schools worldwide to apply some of the ways that they use to achieve such quality and reputation

Simulation Studies of the NLC with Improved Ground Motion Models

The performance of various systems of the Next Linear Collider (NLC) have been studied in terms of ground motion using recently developed models. In particular, the performance of the beam delivery system is discussed. Plans to evaluate the operation of the main linac beam-based alignment and feedback systems are also outlined.Comment: Submitted to XX International Linac Conferenc

Sensitivity Analysis of a Bidirectional Wireless Charger for EV

Bidirectional chargers are required to fully integrate Electric Vehicle (EV) into the smart grids. Additionally, wireless chargers ease the charge/discharge process of the EV batteries so that they are becoming more popular to fulfill a V2G scenario. When considering the load of wireless chargers, it is a requirement to know the real output power that these systems offer. The designed output power may differ from the real one as components suffer from tolerance. This paper defines six sensitivity factors to model the severity of the effects of tolerance into the output power. To do so, an electric circuit analysis is used and a mathematical formulation is derived. The six sensitivity factors are computed for a laboratory prototype.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Federal Regulation of Pesticide Residues: A Brief History and Analysis

In the United States today, there are over 900 pesticides in use1 and over 400 are approved for use in food production, whether used as part of the growing process or in post-harvest handling. Although the history of pesticide use in food crops goes back centuries, the post-war period has seen an enormous growth in the varieties and amounts of pesticides used in our food system. As our reliance on pesticides has grown, pesticides have become a divisive issue. Pesticide advocates view them as essential to a secure and reliable food supply needed to feed a growing world population. Detractors, however, point out the public health risks—both known and not yet fully understood—that widespread pesticide use may entail. Meanwhile, consumer demand for products grown without the use of pesticides is increasing, while at the very same moment farmers are applying more and different pesticides to combat pesticide-resistant “superweeds.” These tensions are playing out both globally and locally in a variety of arenas, from debates over pesticide bans within international organizations and national governments, to the litigation of personal injury claims in American courts

A Dimension-Adaptive Multi-Index Monte Carlo Method Applied to a Model of a Heat Exchanger

We present an adaptive version of the Multi-Index Monte Carlo method, introduced by Haji-Ali, Nobile and Tempone (2016), for simulating PDEs with coefficients that are random fields. A classical technique for sampling from these random fields is the Karhunen-Lo\`eve expansion. Our adaptive algorithm is based on the adaptive algorithm used in sparse grid cubature as introduced by Gerstner and Griebel (2003), and automatically chooses the number of terms needed in this expansion, as well as the required spatial discretizations of the PDE model. We apply the method to a simplified model of a heat exchanger with random insulator material, where the stochastic characteristics are modeled as a lognormal random field, and we show consistent computational savings

Guided resonances in photonic crystals with point-defected aperiodically-ordered supercells

In this paper, we study the excitation of guided resonances (GRs) in photonic-crystal slabs based on point-defected aperiodically-ordered supercells. With specific reference to perforated-slab structures and the Ammann-Beenker octagonal lattice geometry, we carry out full-wave numerical studies of the plane-wave responses and of the underlying modal structures, which illustrate the representative effects induced by the introduction of symmetry-preserving and symmetry-breaking defects. Our results demonstrate that breaking the supercell mirror symmetries via the judicious introduction of point-defects enables for the excitation of otherwise uncoupled GRs, with control on the symmetry properties of their field distributions, thereby constituting an attractive alternative to those GR-engineering approaches based on the asymmetrization of the hole shape. In this framework, aperiodically-ordered supercells seem to be inherently suited, in view of the variety of inequivalent defect sites that they can offer.Comment: 13 pages, 12 figures, 1 table. Slight change in the title; major changes in the text and figure