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61.
Li‐Chen Ou M. Ronnier Luo Pei‐Li Sun Neng‐Chung Hu Hung‐Shing Chen Shing‐Sheng Guan Andrée Woodcock José Luis Caivano Rafael Huertas Alain Treméau Monica Billger Hossein Izadan Klaus Richter 《Color research and application》2012,37(1):23-43
Psychophysical experiments were conducted in the UK, Taiwan, France, Germany, Spain, Sweden, Argentina, and Iran to assess colour emotion for two‐colour combinations using semantic scales warm/cool, heavy/light, active/passive, and like/dislike. A total of 223 observers participated, each presented with 190 colour pairs as the stimuli, shown individually on a cathode ray tube display. The results show consistent responses across cultures only for warm/cool, heavy/light, and active/passive. The like/dislike scale, however, showed some differences between the observer groups, in particular between the Argentinian responses and those obtained from the other observers. Factor analysis reveals that the Argentinian observers preferred passive colour pairs to active ones more than the other observers. In addition to the cultural difference in like/dislike, the experimental results show some effects of gender, professional background (design vs. nondesign), and age. Female observers were found to prefer colour pairs with high‐lightness or low‐chroma values more than their male counterparts. Observers with a design background liked low‐chroma colour pairs or those containing colours of similar hue more than nondesign observers. Older observers liked colour pairs with high‐lightness or high‐chroma values more than young observers did. Based on the findings, a two‐level theory of colour emotion is proposed, in which warm/cool, heavy/light, and active/passive are identified as the reactive‐level responses and like/dislike the reflective‐level response. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2012 相似文献
62.
Th. Richter 《Journal of Modern Optics》2013,60(8):1735-1749
Abstract We consider double balanced homodyne detection schemes with and without (local oscillator) phase-randomized detection. We discuss the reconstruction of the photon statistics from phase-randomized measurements. We show how the Wigner function of a photon-number state can be synthesized from phase-randomized double homodyne measurements of two properly prepared field states. Moreover we propose a new procedure to determine the whole density matrix from the Q function. Finally we express the Q function in terms of normally ordered moments and discuss their reconstruction. 相似文献
63.
Professional order‐picking in deep cold‐storage depots (i.e., storing, picking, and dispatching of frozen groceries) requires employees to remain working at temperatures of approximately ?24°C for a whole workday. Actually, a well‐regulated organization of working times and breaks has not been established, and no competent knowledge exists as to whether an additional age‐differentiated organization is necessary. To assess the physiological effects while working in deep cold, 30 male subjects (Ss) were classified into two age groups (20‐ to 35‐year‐olds and 40‐ to 65‐year‐olds). In whole workday tests, possible age‐dependent effects on the strain were measured to guarantee the preservation of the subjects' ability to work in the long run. For the objectification of the physiological strain, heart rate and skin surface temperature were registered continuously, and blood pressure and body core temperature were measured and recorded discretely during cold exposures of 80, 100, and 120 min, separated by 20‐min warming‐up breaks. Systematic differences of blood pressure could not be found. The heart rate values indicated a high physiological strain for both younger and older Ss, with work‐related increases above the resting level of 30 bpm and more. Due to increases over time, endurance level sometimes was exceeded. Age‐related differences in skin temperature could not be recorded, but the ability to generate heat deteriorated with advancing age, which is shown by more substantial decreases of body core temperature in the group of 40‐ to 65‐year‐olds taken at the tympanum. Regarding physiological strain brought about by maximum heart rate decreasing with age and declined heat generation, correspondingly adapted workday break regimes have to be provided for older employees to ensure their ability to work in the long run. © 2011 Wiley Periodicals, Inc. 相似文献
64.
R. Neveling H. Fujita F.D. SmitT. Adachi G.P.A. BergE.Z. Buthelezi J. CarterJ.L. Conradie M. CouderR.W. Fearick S.V. FörtschD.T. Fourie Y. FujitaJ. Görres K. HatanakaM. Jingo A.M. KrumbholzC.O. Kureba J.P. MiraS.H.T. Murray P. von Neumann-CoselS. O’Brien P. Papka I. PoltoratskaA. Richter E. Sideras-HaddadJ.A. Swartz A. TamiiI.T. Usman J.J. van ZylJ. Mabiala 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2012,662(1):101
65.
66.
Flame-assisted spray pyrolysis (FASP) is a versatile process for synthesis of nanoparticles from a broad choice of precursors and solvents. Water is an attractive solvent particularly for inexpensive inorganic precursors (e.g. metal nitrates) as it can effectively reduce the process cost. Furthermore when water usage is combined with a carbon-free fuel (e.g. H2), nanoparticles can be made without forming CO2. Here such a FASP process is explored for synthesis of Bi2O3 and other oxide nanoparticles from aqueous precursor solutions. The flame temperature was measured by FTIR emission–transmission spectroscopy while powders were characterized by X-ray diffraction and N2 adsorption. At low FASP fuel gas (H2 or C2H2) flow rates or process temperatures, product powders had a bimodal crystal size distribution. Its large and small modes were made by droplet- and gas-to-particle conversion, respectively. Homogeneous Bi2O3 and CeO2 powders were obtained for sufficiently high flow rates of either C2H2 or H2. Prolonged high temperature residence times promoted precursor evaporation from the spray droplets and yielded homogeneous nanostructured powders by gas-to-particle conversion. In contrast, FASP of aqueous solutions of aluminum nitrate yielded rather large particles by droplet-to-particle conversion at all fuel flows investigated. 相似文献
67.
Alexander W. Richter Nathaniel A. Throckmorton Todd B. Walker 《Computational Economics》2014,44(4):445-476
Policy function iteration methods for solving and analyzing dynamic stochastic general equilibrium models are powerful from a theoretical and computational perspective. Despite obvious theoretical appeal, significant startup costs and a reliance on grid-based methods have limited the use of policy function iteration as a solution algorithm. We reduce these costs by providing a user-friendly suite of MATLAB functions that introduce multi-core processing and Fortran via MATLAB’s executable function. Within the class of policy function iteration methods, we advocate using time iteration with linear interpolation. We examine a canonical real business cycle model and a new Keynesian model that features regime switching in policy parameters, Epstein–Zin preferences, and monetary policy that occasionally hits the zero-lower bound on the nominal interest rate to highlight the attractiveness of our methodology. We compare our advocated approach to other familiar iteration and approximation methods, highlighting the tradeoffs between accuracy, speed and robustness. 相似文献
68.
69.
A recently introduced hierarchy of necessary and sufficient conditions for non-classicality of a quantum state [Th. Richter and W. Vogel, Phys. Rev. Lett. 89 283601 (2002)] is applied to the characterization of phase-insensitive quantum states. Even under such conditions it may be important to analyse the relation between different phase values in the quadrature distributions in order to demonstrate the non-classical nature of the state under study. 相似文献