Complementary monostable circuits achieve low power drain and high reliability

Two-transistor multivibrator has minimum power dissipation and maximum reliability. It minimizes the use of components that are subject to environmental changes or other unpredictable behavior

Variable voltage supply uses Zener dioxide as reference

Using a zener diode as the reference element, a simple transistorized circuit provides a stable variable reference voltage

Position location and data collection system and method Patent

Development of telemetry system for position location and data acquisitio

An improved time of flight gamma-ray telescope to monitor diffuse gamma-ray in the energy range 5 MeV - 50 MeV

A time of flight measuring device is the basic triggering system of most of medium and high energy gamma-ray telescopes. A simple gamma-ray telescope has been built in order to check in flight conditions the functioning of an advanced time of flight system. The technical ratings of the system are described. This telescope has been flown twice with stratospheric balloons, its axis being oriented at various Zenital directions. Flight results are presented for diffuse gamma-rays, atmospheric secondaries, and various causes of noise in the 5 MeV-50 MeV energy range

Learning Statistics Through Exemplars

This paper implements recent proposals for enhancing the learning of mathematics by developing statistics instruction and assessment for eighth grade students that c^italizes on the use of exemplars. The goal of instruction was for small groups to learn about statistics by engaging in hands-on activities as well as to ^ply their knowledge and skills by creating statistics projects tfiat involved designing, conducting, and presenting a mini-experimeni. Performance criteria which reflected the statistical concepts taught in the instruction were explained to students to ensure their understanding of the task (i.e., project). Groups were assigned to two treatments-exemplars and nonexemplars?Av'hich differed in the degree to which criteria modeled the processes of hypothesis generation, data collection, data analysis, and graphic representation. The effectiveness of elaborating on criteria through examples and text (i.e., exemplars) or just text (i.e., nonexemplars) for enhancing learning was examined. Both treatments demonstrated significant performance gains from pretest to posttest. However, students' understanding of representative sampling was significantly better as a result of receiving the exemplars treatment than the nonexemplars treatment. Making criteria more elaborate through examples of performance can thus enhance students' understanding of more abstfact statistical concepts such as sampling

Properties of a carbon-fibre composite modified by electrospun poly (vinylidene fluoride)

The interlaminar toughening of a carbon-fibre reinforced composite by incorporation of electrospun polyvinylidene fluoride (PVDF) nanofibrous membranes was explored in this work. The nanofibres were electrospun directly onto commercial pre-impregnated carbon fibre materials under optimised conditions and PVDF was found to primarily crystallise in its β phase polymorphic form. There is strong evidence from DMTA analysis to suggest that a partial miscibility between the amorphous phases of the PVDF nanofibres and the epoxy exists. The improved plastic deformation at the crack tip after inclusion of the nanofibres was directly translated to a 57% increase in the mode II interlaminar fracture toughness (in-plane shear failure). Conversely, the fracture toughness in mode I (opening failure) was slightly lower than the reference by approximately 20%, and the results were interpreted from the complex micromechanisms of failure arising from the changes in polymorphism of the PVDF

La réforme des retraites de 1993 : quel impact sur l'équivalent patrimonial des droits à retraite ?

Depuis 1993, la France a enregistré plusieurs réformes de son système de retraites, visant avant tout à en assurer la soutenabilité. Cette contribution a pour objectif d’évaluer l’impact de la réforme de 1993 sur l’équivalent patrimonial des droits individuels à la retraite (EPDR), c\u27est-à-dire la somme actuarielle probable des pensions à recevoir, de la date de liquidation des droits jusqu’au décès. Plus précisément, nous mesurons l’impact de cette réforme sur l’EPDR des mono-pensionnés du régime général, à l’aide des données de l’Echantillon Interrégimes de Retraités 2008. Parmi les mesures phares de la réforme de 1993 figure l’augmentation progressive de la durée de cotisation nécessaire pour obtenir une retraite à taux plein au régime général. Cette augmentation est susceptible d’engendrer deux effets opposés : un effet de report de l’âge de liquidation pour conserver un EPDR adéquat pour ses vieux jours (voire l’augmenter) ou un effet de décote, si l’assuré-e ne souhaite, ou ne peut, pas prolonger son activité et subit donc une décote sur sa pension, et partant sur son EPDR. Pour tester les effets nets de la réforme de 1993 sur l’EPDR, nous procédons à des estimations économétriques en différences premières et en doubles différences, ainsi qu’à des estimations par quantiles pour mesurer les impacts le long de la distribution de l’EPDR. Nos estimations montrent des résultats différents selon que les individus partent avant ou après 2004, date d’entrée en vigueur de la réforme. Ainsi, toutes choses égales par ailleurs, un départ en retraite avant 2004 plutôt que postérieurement, augmente l’EPDR des retraités concernés. Toutefois, l’interaction avec les autres variables nuance cette conclusion. D’une part, reporter son départ en retraite réduit l’EPDR moyen d’environ 20% : le report permet d’accumuler des droits supplémentaires, mais sur une période réduite. D’autre part, l’effet de la décote est négatif, mais son intensité est réduite quand les retraités reportent leur départ. En outre, comme les générations 1934-1943 ont subi conjointement les réformes de 1993 et 2003, nos estimations en double différence permettent d’isoler l’effet « pur » de la réforme de 1993 : lorsque les affiliés ont subi une décote, sans avoir reporté leur départ en retraite pour l’atténuer, la liquidation des droits aux conditions de 2003 par rapport aux conditions de 1993 est la plus défavorable. Enfin, les estimations par quantiles montrent que ces effets s’intensifient dans la première moitié de la distribution, et s’atténuent au-delà

Pension Wealth in France: An Assessment on Panel Data

This contribution proposes a measure of pension wealth in the French public PAYG schemes (first and second pillar schemes) and of its distribution among the population of retirees in 2008 using the Echantillon Inter régimes de Retraités (EIR) panel data. We show that aggregate pension wealth amounts to around 4765 billion Euros assuming a 2 percent discount rate. There are significant differences in the amount of individual’s pension wealth between the pension schemes of the private and public sector. Moreover, there is more inequality in the distribution of pension wealth among private sector retirees than public sectorones