Magnetic spring in oscillating mirror linear scanner for satellite camera

One of the main difficulties encountered in the development of a multispectral scanner is the realization of an oscillating mechanical device. A magnetic device which is characterized by the absence of friction is presented. The main developments concern the analysis of magnetic forces. A preliminary project of a device which could be used in a satellite is presented

Moving forward with combinatorial interaction testing

Combinatorial interaction testing (CIT) is an efficient and effective method of detecting failures that are caused by the interactions of various system input parameters. In this paper, we discuss CIT, point out some of the difficulties of applying it in practice, and highlight some recent advances that have improved CIT’s applicability to modern systems. We also provide a roadmap for future research and directions; one that we hope will lead to new CIT research and to higher quality testing of industrial systems

Inelastic Light Scattering Processes

Five different inelastic light scattering processes will be denoted by, ordinary Raman scattering (ORS), resonance Raman scattering (RRS), off-resonance fluorescence (ORF), resonance fluorescence (RF), and broad fluorescence (BF). A distinction between fluorescence (including ORF and RF) and Raman scattering (including ORS and RRS) will be made in terms of the number of intermediate molecular states which contribute significantly to the scattered amplitude, and not in terms of excited state lifetimes or virtual versus real processes. The theory of these processes will be reviewed, including the effects of pressure, laser wavelength, and laser spectral distribution on the scattered intensity. The application of these processes to the remote sensing of atmospheric pollutants will be discussed briefly. It will be pointed out that the poor sensitivity of the ORS technique cannot be increased by going toward resonance without also compromising the advantages it has over the RF technique. Experimental results on inelastic light scattering from I(sub 2) vapor will be presented. As a single longitudinal mode 5145 A argon-ion laser line was tuned away from an I(sub 2) absorption line, the scattering was observed to change from RF to ORF. The basis, of the distinction is the different pressure dependence of the scattered intensity. Nearly three orders of magnitude enhancement of the scattered intensity was measured in going from ORF to RF. Forty-seven overtones were observed and their relative intensities measured. The ORF cross section of I(sub 2) compared to the ORS cross section of N2 was found to be 3 x 10(exp 6), with I(sub 2) at its room temperature vapor pressure

The Effect of Metacognitive and Self-Regulatory Strategy Instruction on Impoverished Students\u27 Assessment Achievement in Physics

The purpose of this nonequivalent control group design study was to evaluate the effectiveness of metacognitive and self-regulatory strategy use on the assessment achievement of 215 9th-grade, residential physics students from low socioeconomic status (low-SES) backgrounds. Students from low-SES backgrounds often lack the self-regulatory habits and metacognitive strategies to improve academic performance. In an effort to increase these scores and to increase student self-regulation and metacognition with regard to achievement in physics, this study investigated the use of metacognitive and self-regulatory strategies specifically as they apply to students\u27 use of their own assessment data. Traditionally, student performance data is used by adults to inform instructional and curricular decisions. However, students are rarely given or asked to evaluate their own performance data. Moreover, students are not shown how to use this data to plan for or inform their own learning. It was found that students in the overall and algebra-ready treatment groups performed significantly better than their control group peers. These results are favorable for inclusion of strategies involving self-regulation and metacognition in secondary physics classrooms. Although these results may be applicable across residential, impoverished populations, further research is needed with non-residential populations

Hybrid modal realism debugged

This paper is part of a PhD project conducted thanks to a scholarship of the ‘School of Philosophical, Anthropological and Film Studies’ at the University of St Andrews and a doctoral contract at Sorbonne Université.In this paper, I support a hybrid view regarding the metaphysics of worlds. I endorse Lewisian Modal Realism for possible worlds (LMR). My aim is to come up with a hybrid account of impossible worlds that provides all the plenitude of impossibilities for all fine-grained intentional contents. I raise several challenges for such a plenitudinous hybrid theory. My version of hybrid modal realism builds impossible worlds as set-theoretic constructions out of genuine individuals and sets of them, that is, as set-theoretic constructions from parts and sets of parts of genuine Lewisian worlds. Structured worlds are defined as sets of tuples: structured entities built out of Lewisian ‘raw material’. These structured worlds are ersatz worlds, some of which are impossible. I claim that propositions must be sets of worlds rather than members of sets. Once the construction is in place, I evaluate the proposal and show that my hybrid account is able to supply a plenitude of impossibilities and thus giving the resources to make all the hyperintensional distinctions we are looking for, whilst remaining Lewisian-conservative.Publisher PDFPeer reviewe

Total synthesis of cruentaren A

Cruentaren A, a highly cytotoxic metabolite, which also inhibits F-ATPase, was synthesized using our recently developed methodology on resorcylic acid lactones natural products. [Molecular structure diagrams appear here. To view, please open pdf attachment] Alcohol A was prepared on a multigram scale in 13 steps starting from (S)-Roche ester and using highly stereoselective reactions such as Evans aldol reaction and asymmetric propargylation. [Molecular structure diagrams appear here. To view, please open pdf attachment] Key fragment B was synthesized in 11 steps from 1,3-propanediol. The 1,2-anti-configuration was installed with a Brown crotylation. Diketo-dioxinone D was generated from C-acylation between Weinreb amide B and keto-dioxinone C. Ketene generation by thermolysis followed by trapping with alcohol A and aromatization afforded resorcylate derivative E. [Molecular structure diagrams appear here. To view, please open pdf attachment] Finally after a sequence consisting of the following key steps: ring closing alkyne metathesis, coupling between amine G and acid H and Lindlar hydrogenation, cruentaren A was obtained. [Molecular structure diagrams appear here. To view, please open pdf attachment