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101.
The past decade has seen a considerable development of techniques designed to help decision makers faced with problems involving conflicting objectives. In particular, a family of methods known collectively as interactive multi-objective programming has come to the fore. This paper presents the underlying rationale of such methods, albeit as seen by a devil's advocate, briefly surveys some areas of application, but then questions the validity of these methods because their assumptions are not supported by the empirical results of behavioural decision theory.  相似文献   
102.
This article was originally published in French in the February 1987 issue of Pour la Science. The translation was done by the author.  相似文献   
103.
104.
A pulsed nozzle source has been installed in the electron diffraction unit at the University of Michigan. The pulsed mode of operation is found to offer several important advantages in the investigation of clusters generated in nozzle flow. These advantages, including the feasibility of operating without a skimmer, are discussed. Design features and characteristic results are briefly outlined.  相似文献   
105.
We have studied the andK systems centrally produced in proton proton collisions at 300 GeV/c and +/p proton collisions at 85 GeV/c using the CERN spectrometer. Clear evidence forS */f o(975) production is observed. An analysis performed on the + mass spectrum in the 1.0 GeV region, using a coupled channel formalism, shows that it is possible to describe theS */f o(975) effect with one single resonance once interference of theS */f o(975) with theS-wave background is introduced. The resultingS */f o(975) parameters arem o =979±4MeV,g =0.28±0.04,g K =0.56±0.18 corresponding to a pole position on sheet II at (1001±2)–i(36±4) MeV. Evidence is also found for a structure having a mass of 1472±12 MeV and a width of 195±33 MeV.  相似文献   
106.
107.
The reactionppp f (K + K -π+π-)p s , where theK + K ? π+π- system is centrally produced, has been studied at 300 GeV/c. TheK *0 \(K^{*0} \bar K^{*0} \) final state has been observed and the cross sections for its central production are found to be the same at 300 and 85 GeV/c. TheK *0 \(K^{*0} \bar K^{*0} \) final state appears to be produced as a non-resonant threshold enhancement.  相似文献   
108.
The relative availabilities of hydroxyl groups at C(2), C(3), and C(6) on the D -glucopyranosyl units of a particular, highly ordered hydrocellulose II have been studied by means of the reaction of N,N-diethylaziridinium chloride, which introduces 2-(diethyl-amino)ethyl substituents. The hydrocellulose II was formed by hydrolysis of fibrous cotton cellulose II during 40 min reflux in 2.5M hydrochloric acid and is designated EHC-II (exemplar hydrocellulose II) because it represents the most highly ordered (crystalline) particles in a series of hydrocelluloses. The deviation in the distribution of substituents among the 2-O-, 3-O-, and 6-O- positions of the D -glucopyranosyl units in EHC-II from that in a disordered cellulose, in which the three types of hydroxyl groups are equally available, is the basis for estimated availabilities of the three types of hydroxyl groups on the surfaces of elementary fibrils in EHC-II. The experimental values of relative availabilities of O(2)H:O(3)H:O(6)H for EHC-II were 1.0:0.26:0.72 compared to estimated values of 1.0:0.0:.075 for surfaces of elementary fibrils of an idealized, perfectly ordered cellulose II, a model that is based on intensities of x-ray diffraction peaks.  相似文献   
109.
The first passive mode locking of the continuous wave (cw) DCM dye laser is reported. Subpicosecond pulses as short as 0.68 ps were obtained over the spectral region from 655 to 673 nm from a simple linear cavity with no dispersion optimisation. The dye 1,3 Diethyl 4,2 quinolythiacarbocyanine iodide (DQTCI) was used as the saturable absorber.  相似文献   
110.
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