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51.
A fundamental question of human society is the evolution of cooperation. Many previous studies explored this question via setting spatial background, where players obtain their payoffs by playing game with their nearest neighbors. Another undoubted fact is that the environment plays an important role in the individual development. Inspired by these phenomena, we reconsider the definition of individual fitness which integrates the environment, denoted by the average payoff of all individual neighbors, with the traditional individual payoffs by introducing a selection parameter u. Tuning u equal to zero returns the traditional version, while increasing u bears the influence of environment. We find that considering the environment, i.e., integrating neighborhoods in the evaluation of fitness, promotes cooperation. If we enhance the value of u, the invasion of defection could be resisted better. We also provide quantitative explanations and complete phase diagrams presenting the influence of the environment on the evolution of cooperation. Finally, the universality of this mechanism is testified for different neighborhood sizes, different topology structures and different game models. Our work may shed light on the emergence and persistence of cooperation in our life. 相似文献
52.
J.M. Cabello F. Ruiz B. Pérez-Gladish P. Méndez-Rodríguez 《European Journal of Operational Research》2014
Socially Responsible Investing (SRI) is broadly defined as an investment process that integrates not only financial but also social, environmental, and ethical (SEE) considerations into investment decision making. SRI has grown rapidly around the world in the last decades. In the last years, given the causes of the 2008 financial crisis, ethical, social, environmental and governance concerns have become even more relevant investment decision criteria. However, while a diverse set of models have been developed to support investment decision-making based on financial criteria, models including also social responsibility criteria are rather scarce. 相似文献
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焦黎 《新疆师范大学学报(自然科学版)》1999,(3)
环境质量评价指数方法是认识和研究环境及对环境质量优劣进行定量描述的一种科学方法。本文通过对此方法的比较分析,提出其在具体实践应用中所存在的问题与不足,同时提出了解决问题的途径和办法。 相似文献
55.
Y. Nagasoe N. Ichiyanagi H. Okabayashi S. Nave J. Eastoe C. J. O'Connor 《Colloid and polymer science》1999,277(10):947-956
A homologous series of sodium dialkylsulfosuccinates (SDAS) has been synthesized with various chain lengths (dibutyl, dihexyl,
diheptyl, dioctyl, dinonyl, didecyl, diundecyl and didodecyl). These compounds are straight-chain analogues for Aerosol-OT.
Raman scattering spectra have been recordered for these SDAS compounds, both in the solid state and in aqueous solutions.
These spectra are analyzed in detail in the CH stretch and CH2 deformation regions, and the results depend specifically on the length of the hydrocarbon chain. In particular, the longitudinal
accordion-like vibrational modes coming from the all-trans n-alkyl chains have been investigated. For the SDAS dihydrates, all hydrocarbon chains take up an extended form, whereas for
the monohydrates the tails tend to become disordered at the CH2-CH2 single bond close to the terminal methyl groups. It has also been confirmed that for the concentrated aqueous SDAS (sodium
dibutylsulfosuccinate – sodium dioctylsulfosuccinate) samples preferential stabilization of the extended conformation of the
hydrocarbon chain may occur.
Received: 23 February 1999 Accepted: 10 May 1999 相似文献
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本文从环境保护的角度出发,根据无机化学实验的特点,结合本人具体的教学实践,简要介绍了在无机化学实验教学过程中贯彻绿色化学思想的意义和方法。 相似文献
58.
In the paper machine vision, laser interferometer and coordinate measuring machine (CMM) are combined to develop a vision inspection system. The measurement capability of the developed system is investigated by measuring the distances between the lines on a standard line scale. The vision camera is used to replace the probe of the CMM to take the images of the interested lines on a line scale at two different positions. Meanwhile, the displacement of the CCD camera is measured using laser interferometer. Using subpixel edge localization and outlier-excluding least-squares regression, the distance between two interested lines is computed under an image plane coordinate system. By adding the displacement of the CCD camera measured using laser interferometer, the line space can be determined. Experiments have been performed repeatedly to measure the line space on the 1.00 and 300.0 mm line scales. Results indicate that the measured data only have a little fluctuation and are close to those obtained by the NML (National Measurement Laboratory, Taiwan). 相似文献
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南京市地铁工程环境地质评价 总被引:2,自引:0,他引:2
地下空间的开发不可避免会对周围的环境造成影响 ,本文通过结合南京工程地质水文地质情况和地铁的施工 ,就地铁工程对环境的影响进行初步研究 ,并提出解决方法 相似文献