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991.
为探究明度与色相同步变化时不同分级设色方案在数字环境下的适宜性,基于Munsell色彩调和秩序与CIEDE2000色差公式设计了7种分级设色方案,并开展了视觉认知试验。试验结果表明:①增加各级间色差会导致颜色辨识的准确性增强;②与各级间色差相等的色阶相比,色差先增大后减小的色阶有利于读图判别;③图斑面积分布均匀程度对颜色辨识的影响并不显著;④色阶的总色差增大,会导致颜色过渡的协调性降低。色差先增大后减小的色阶能产生较好的辨识效果,同时保持较好的色彩协调性,且相关规律可以推广到图斑面积分布均匀程度不同的地图中,在分级设色中运用具有优势。 相似文献
992.
Many countries around the world respond to global warming and its consequences with various policy instruments. In the economic literature, policy instruments have typically been analysed with respect to efficiency, but little effort has been expended to understand public preferences for these instruments. In an internet-based choice experiment to address this shortcoming, Swedes were asked to choose between two alternative hypothetical policy instruments, each of which reduces CO2 emissions by the same amount. The hypothetical policy instruments were characterized by a number of specific attributes. By varying the levels of each of the attributes, respondents indirectly reveal their preferences for these attributes. Half of the respondents are faced with choices labelled ‘tax’ and ‘other’, and the other half are faced with unlabelled choices (hypothetical instruments). The results show that Swedes tend to dislike the term ‘tax’ and show a preference for instruments with a positive effect on environment-friendly technology and climate awareness. A progressive-like cost distribution is preferred to a regressive cost distribution, and the private cost is negatively related to the choice of policy. 相似文献
993.
Strategic issue framing is widely regarded as an effective communication strategy to alter public opinion and citizens’ policy support. However, it is unclear to what extent strategic framing can increase support for ambitious demand-side actions and policies that make the cost of mitigation perceptible in citizens’ everyday lives. Taking an exploratory approach, we conducted qualitative interviews and a comparative framing experiment with 9,750 survey respondents from China, Germany, and the United States. We analyzed strategic issue framing effects in two areas known to be key for increasing the sustainability of consumption: meat/fish consumption, and fossil-fuel car usage. Employing both classical linear regressions and advanced Bayesian sparse estimations, we show that in all three countries widespread arguments in favor of reduced meat/fish consumption and car use are unlikely to substantially alter citizens’ concern, willingness to pay, behavioral intentions and policy support for demand-side action. Our findings suggest that in the absence of a broader behavioral change campaign, strategic issue framing alone is unlikely to be effective in changing entrenched attitudes and behaviors. On its own, it is also unlikely to substantially increase public support for demand-side policies to reduce consumption. More careful research is needed to help policymakers understand the role and limits of different strategic framing techniques. 相似文献
994.
995.
PS剂驱油矿场先导性试验研究 总被引:1,自引:1,他引:1
PS碱木素磺酸盐 (简称 PS剂 )是由造纸废液经浓缩加入酚、醛和硫酸等在高温下复配或反应后提炼出的 1种新型表面活性剂。由于其具有降低原油粘度和油水界面张力的特性[1 -2 ] ,因而可作为提高原油采收率的驱替剂应用到油田开采中。本文通过室内实验和 W31断块的现场驱替试验 ,进一步探讨了 PS剂的驱替机理和驱油效果、探索了注 PS剂驱油的现场经验。 相似文献
996.
A major goal of the BepiColombo mission to Mercury is the determination of the structure and state of Mercury's interior. Here the BepiColombo rotation experiment has been simulated in order to assess the ability to attain the mission goals and to help lay out a series of constraints on the experiment's possible progress. In the rotation experiment pairs of images of identical surface regions taken at different epochs are used to retrieve information on Mercury's rotation and orientation. The idea is that from observations of the same patch of Mercury's surface at two different solar longitudes of Mercury the orientation of Mercury can be determined, and therefore also the obliquity and rotation variations with respect to the uniform rotation.The estimation of the libration amplitude and obliquity through pattern matching of observed surface landmarks is challenging. The main problem arises from the difficulty to observe the same landmark on the planetary surface repeatedly over the MPO mission lifetime, due to the combination of Mercury's 3:2 spin-orbit resonance, the absence of a drift of the MPO polar orbital plane and the need to combine data from different instruments with their own measurement restrictions.By assuming that Mercury occupies a Cassini state and that the spacecraft operates nominally we show that under worst case assumptions the annual libration amplitude and obliquity can be measured with a precision of, respectively, 1.4 arcseconds (as) and 1.0 as over the nominal BepiColombo MPO lifetime with about 25 landmarks for rather stringent illumination restrictions. The outcome of the experiment cannot be easily improved by simply relaxing the observational constraints, or increasing the data volume. 相似文献
997.
A stochastic error process of curves is proposed as the error model to describe the errors of curves in GIS. In terms of the stochastic process, four characteristics concerning the local error of curves, namely, mean error function, standard error function, absolute error function, and the correlation function of errors, are put forward. The total error of a curve is expressed by a mean square integral of the stochastic error process. The probabilistic meanings and geometric meanings of the characteristics mentioned above are also discussed. A scan digitization experiment is designed to check the efficiency of the model. In the experiment, a piece of contour line is digitized for more than 100 times and lots of sample functions are derived from the experiment. Finally, all the error characteristics are estimated, on the basis of sample functions. The experiment results show that the systematic error in digitized map data is not negligible, and the errors of points on curves are chiefly dependent on the curvature and the concavity of the curves. 相似文献
998.
以马达加斯加红土型三水铝石铝土矿为研究对象,通过矿物物理学研究、室内样品破碎、湿筛试验,研究了马达加斯加三水型铝土矿的可选性。并进一步对破碎、湿筛所得的精矿进行拜耳法溶出试验和沉降试验研究,揭示了马达加斯加红土型—三水铝石铝土矿精矿的拜耳法溶出性质和赤泥的沉降性质,为马达加斯加铝土矿选矿和冶炼提供了参考依据。 相似文献
999.
秦岭成矿带Pb、Zn化探异常与铅锌矿
常无对应关系的原因 总被引:1,自引:0,他引:1
秦岭成矿带中Pb、Zn化探异常区常无铅锌矿,而铅锌矿区又常无Pb、Zn异常,这种Pb、Zn异常与铅锌矿的不对应关系,通常导致大量的Pb、Zn异常无找矿指示意义,甚至给找矿评价、勘查部署选区工作带来了某些误导。本次的大量实验研究表明,秦岭地区水系沉积物中Pb、Zn元素主要在较粗粒级(-10~+60目)组分和细粒(小于140目)组分两端粒级中富集,而在中等粒度(80~120目)中贫化。以往所采用的统一粒度(-60目)样品分析所圈定的Pb、Zn异常,主要是细粒级吸附态的Pb、Zn在远离铅锌矿源区富集的反映,强化了远离矿源“次生富集”的信息。据此建议,在秦岭地区开展的面积性化探工作中,首先通过典型矿区粒级试验,建立区内不同背景区成矿元素的合理粒级范围,使所选用的粒度组合(粗、中、细粒)对在不同粒级中富集的元素更具代表性,改变秦岭Pb、Zn等化探异常指导找矿工作的被动局面,确保化探工作能更好地指导地质找矿和勘查部署选区工作。 相似文献
1000.
海相烃源岩二次生烃潜力定量评价新方法 总被引:1,自引:0,他引:1
烃源岩二次生烃的演化过程是残余干酪根热解演化与残留油热裂解转化两个既相互联系又完全不同的物理化学反应过程的叠加。本文利用自制高压釜热压生烃模拟实验装置,采取分阶段连续递进模拟实验方式,以海相烃源岩样品为例分别评价了残余干酪根的生烃潜力与残留可溶有机质转化油气潜力,建立了一套不同起始与终止成熟度海相烃源岩二次生烃潜力的定量评价方法,并首次明确提出了干酪根生油指数KIo、干酪根生气指数KIg、干酪根生烃指数KIh等评价烃源岩生烃潜力的参数,弥补了ROCK EVAL热解评价方法无法分别评价烃源岩在不同生烃演化阶段所生成的“油”或“烃气”潜力的不足。 相似文献