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1.
This work is concerned with the prediction of visual colour difference between pairs of palettes. In this study, the palettes contained five colours arranged in a horizontal row. A total of 95 pairs of palettes were rated for visual difference by 20 participants. The colour difference between the palettes was predicted using two algorithms, each based on one of six colour-difference formulae. The best performance (r2 = 0.86 and STRESS = 16.9) was obtained using the minimum colour-difference algorithm (MICDM) using the CIEDE2000 equation with a lightness weighing of 2. There was some evidence that the order (or arrangement) of the colours in the palettes was a factor affecting the visual colour differences although the MICDM algorithm does not take order into account. Application of this algorithm is intended for digital design workflows where colour palettes are generated automatically using machine learning and for comparing palettes obtained from psychophysical studies to explore, for example, the effect of culture, age, or gender on colour associations.  相似文献   
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We propose a new semantic relation for gradable adjectives in WordNet, which enriches the present, vague, similar relation with information on the degree or intensity with which different adjectives express a shared attribute. Using lexical-semantic patterns, we mine the Web for evidence of the relative strength of adjectives like “large”, “huge” and “gigantic” with respect to their attribute (“size”). The pairwise orderings we derive allow us to construct scales on which the adjectives are located. To represent the intensity relation among gradable adjectives in WordNet, we combine ordered scales with the current WordNet dumbbells based on the relation between a pair of central adjectives and a group of undifferentiated semantically similar adjectives. A new intensity relation links the adjectives in the dumbbells and their concurrent representation on scales. Besides capturing the semantics of gradable adjectives in a way that is both intuitively clear as well as consistent with corpus data, the introduction of an intensity relation would potentially result in several specific benefits for NLP.  相似文献   
4.
基于移动网络流量日志的城市时空行为分析   总被引:1,自引:0,他引:1  
城市的空间组织和居民行为研究是城市地理学研究的重点,随着信息技术的快速发展,居民的时空行为对城市空间的组织和结构的影响呈现出日益增加的趋势,因此,对城市空间以及居民时空行为的深入分析具有很高的研究价值.通过采集杭州市区移动3G网络流量日志,首先采用空间点模式的分析方法研究了城市居民的聚集模式,并研究了居民移动的距离、方向等方面的特征;之后采用网格的方法对城市空间进行分块,并以区块为主体研究了热点区块出现的时空点、区块人流的更迭速率、工作日人流的潮汐效应;提出了区块差异指数的概念,并利用其对区块进行聚类,分析了区块间的相关性和区块间距离之间的关系.由于所研究的数据来源于移动3G网络流量日志,因此具有覆盖面广、数据量大等特点,非常适合从大时空尺度层面研究居民和城市空间活动.  相似文献   
5.
We report a11B NMR line shape and spin-lattice relaxation rate (1/(T 1 T)) study of pure and lightly carbon-doped MgB2−x C x forx=0, 0.02, and 0.04, in the vortex state and in magnetic field of 23.5 kOe. We show that while pure MgB2 exhibits the magnetic field distribution from superposition of the normal and the Abrikosov state, slight replacement of boron with carbon unveils the magnetic field distribution of the pure Abrikosov state. This indicates a considerable increase ofH c 2/c with carbon doping with respect to pure MgB2. The spin-lattice relaxation rate 1/(T 1 T) demonstrates clearly the presence of a coherence peak right belowT c in pure MgB2, followed by a typical BCS decrease on cooling. However, at temperatures lower than ≈10 K strong deviation from the BCS behavior is observed, probably from residual contribution of the vortex dynamics. In the carbon-doped systems both the coherence peak and the BCS temperature dependence of 1/(T 1 T) weaken, an effect attributed to the gradual shrinking of the σ hole cylinders of the Fermi surface with electron doping.  相似文献   
6.
We report a 11B NMR line shape and spin-lattice relaxation rate (1/(T1T))(1/(T_1T)) study of pure and lightly carbon-doped MgB2-xCx_{2-x}{\rm C}_x for x = 0,0.02x = 0,0.02, and 0.04, in the vortex state and in magnetic field of 23.5 kOe. We show that while pure MgB2_2 exhibits the magnetic field distribution from superposition of the normal and the Abrikosov state, slight replacement of boron with carbon unveils the magnetic field distribution of the pure Abrikosov state. This indicates a considerable increase of Hcc2H^c_{c2} with carbon doping with respect to pure MgB2_2. The spin-lattice relaxation rate 1/(T1T)1/(T_1T) demonstrates clearly the presence of a coherence peak right below TcT_{\rm c} in pure MgB2_2, followed by a typical BCS decrease on cooling. However, at temperatures lower than ?\approx 10 K strong deviation from the BCS behavior is observed, probably from residual contribution of the vortex dynamics. In the carbon-doped systems both the coherence peak and the BCS temperature dependence of 1/(T1T)1/(T_1T) weaken, an effect attributed to the gradual shrinking of the σ hole cylinders of the Fermi surface with electron doping.  相似文献   
7.
In order to determine the activities of phosphorus and iron in liquid {Cu‐Fe‐P} alloys, the two coexisting phases of liquid {Cu‐Fe‐P} alloys + <Cu‐Fe‐P> solid solutions were brought into equilibrium with a mixture of Al2O3 + AlPO4 + FexAl2O4 at temperatures of 1416K and 1526K. The oxygen partial pressures were measured with the aid of a solid‐oxide galvanic cell of the type: (+)Mo / Mo + MoO2/ ZrO2(MgO) / {Cu‐Fe‐P} + <Cu‐Fe‐P> + <Al2O3> + <AlPO4> + <FeAl2O4> / Fe(‐) The equilibrium reactions underlying the experiments can be expressed by 2[P]cu + (5/2) (O2) + <Al2O3> = 2 <AlPO4> and x[Fe]Cu + (1/2) (O2) + <Al2O3> = <FexAl2O4> The Henrian activity coefficient referred to 1 wt pct solution in pure liquid copper could be well expressed by the formula log fP° = (4.46±0.40) ‐ (8.67±0.59)/(T/K). The iron activities referred to pure solid iron could be formulated as log aFe =‐ (0.37 ± 0.12) + (500 ±200) /(T/K).  相似文献   
8.
Thermoplastic resins are typically used without any kind of physical aging treatment. For such materials, creep behavior and physical aging, which depend on time and temperature, occur simultaneously. The effects of these processes are evident after quenching and are recorded in the material as a thermal history. This history strongly influences mechanical properties and creep behavior in particular. Thus, a more thorough understanding of the physical aging process is desirable. We examined the creep deformation of polycarbonate (PC) to reveal the effects of physical aging on creep behavior. The effects were dependent on both time and temperature. The relationship between physical aging and creep behavior exemplified superposition principles with regard to time and both pre-test aging time and pre-test aging temperature. The superposition principles allowed the calculation of creep deformations at a given temperature; the calculated results were corroborated by experimental data.  相似文献   
9.
Wheat noodles were prepared using flour to which hydroxypropylated tapioca starch was added, and the effect of this addition on the moisture distribution within the noodles during cooking was examined using a digital image processing technique. The addition of the modified starch slightly increased the moisture content and narrowed the flat distribution near the noodle surface. The distribution features reflected the changes in the water absorption behaviour caused by the properties of the modified starch and the reduction in the gluten content. Addition of the modified starch lowered Young's modulus and the energy for 99% strain of the noodles in the texture analysis to, at maximum 35% and 65%, and decreased the breakability of the noodles. These changes in the moisture distribution and textural properties have been ascribed to changes in both the state of the starch granules near the surface and the structure of the gluten network.  相似文献   
10.
This study aimed at investigating the effect of drying conditions on spaghetti properties, i.e., its color, surface structure, rupture strength, rehydration characteristics, texture, and sauce retention capacity. The effects of temperature and humidity were independently examined under constant drying conditions, which were compared to those applied industrially, where the temperature and relative humidity are changed stepwise with time. The knowledge obtained in this study is considered useful for reasonably determining the drying conditions for producing spaghetti with desired properties.  相似文献   
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