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The quantum Fourier transform offers an interesting way to perform arithmetic operations on a quantum computer. We review existing quantum Fourier transform adders and multipliers and comment some simple variations that extend their capabilities. These modified circuits can perform modular and non-modular arithmetic operations and work with signed integers. Among the operations, we discuss a quantum method to compute the weighted average of a series of inputs in the transform domain. One of the circuits, the controlled weighted sum, can be interpreted as a circuit to compute the inner product of two data vectors.  相似文献   
437.
The new particle formation due to the use of cleaning products containing volatile organic compounds (VOCs) in indoor environments is well documented in the scientific literature. Indeed, the physical-chemical process occurring in particle nucleation due to VOC-ozone reactions was deepened as well as the effect of the main influencing parameters (ie, temperature, ozone). Nonetheless, proper quantification of the emission under actual meteo-climatic conditions and ozone concentrations is not available. To this end, in the present paper the emission factors of newly generated ultrafine particles due to the use of different floor cleaning products under actual temperature and relative humidity conditions and ozone concentrations typical of the summer periods were evaluated. Tests in a chamber and in an actual indoor environment were performed measuring continuously particle number concentrations and size distributions during cleaning activities. The tests revealed that a significant particle emission in the nucleation mode was present for half of the products under investigation with emission factors up to 1.1 × 1011 part./m2 (8.8 × 1010 part./mLproduct), then leading to an overall particle emission comparable to other well-known indoor sources when cleaning wide surfaces.  相似文献   
438.
This work summarizes a test programme carried out in order to further knowledge of the behaviour of beams with wide compression flanges. The influences of the transverse flange reinforcement and of the transverse bending moment in the flange on the strengths of the beams were studied. On the basis of the test results, commentaries on the ACI and CEB-FIP recommendations for the design of the transverse flange reinforcement are made. An alternative design method is also proposed.
Resume Cette étude résume un programme d'essais entrepris pour améliorer la connaissance du comportement de poutres à larges membrures en compression. On a étudié influence du renforcement de membrure transversal et du moment fléchissant transversal dans la membrure sur la résistance des poutres. Sur la base des résultats d'essais, on commente les recommandations ACI et CEB/FIP sur le calcul du renforcement de membrure transversal.

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439.
This paper reports the first application of the multicriteria decision making methods, PROMETHEE and GAIA, to indoor and outdoor air quality data. Fourteen residential houses in a suburb of Brisbane, Australia were investigated for 21 air quality-influencing criteria, which included the characteristics of the houses as well as the concentrations of volatile organic compounds, fungi, bacteria, submicrometer, and supermicrometer particles in their indoor and outdoor air samples. Ranking information necessary to select one house in preference to all others and to assess the parameters influencing the differentiation of the houses was found with the aid of PROMETHEE and GAIA. There was no correlation between the rank order of each house and the health complaints of its occupants. Patterns in GAIA plots show that indoor air quality in these houses is strongly dependent on the characteristics of the houses (construction material, distance of the house from a major road, and the presence of an in-built garage). Marked similarities were observed in the patterns obtained when GAIA and factor analysis were applied to the data. This underscores the potential of PROMETHEE and GAIA to provide information that can assist source apportionment and elucidation of effective remedial measures for indoor air pollution.  相似文献   
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