On Fuzzy Corsini's Hyperoperations

We generalize the concept of C-hyperoperation and introduce the concept of F-C-hyperoperation. We list some basic properties of F-C-hyperoperation and the relationship between the concept of C-hyperoperation and the concept of F-C-hyperoperation. We also research F-C-hyperoperations associated with special fuzzy relations

Potential climate engineering effectiveness and side effects during a high CO2-emissions scenario

The realization that mitigation efforts to reduce CO2 emissions have, until now, been relatively ineffective has led to an increasing interest in climate engineering as a possible means of preventing potentially catastrophic consequences of climate change. While many studies have addressed the potential effectiveness of individual methods there have been few attempts to compare them. We use an Earth system model to compare the effectiveness and side effects of afforestation, artificial ocean upwelling, ocean iron fertilization, ocean alkalinization, and solar radiation management during a high CO2-emissions scenario. We find that even when applied continuously and at scales as large as currently deemed possible, all methods are, individually, either relatively ineffective with limited (<8%) warming reductions, or they have severe side effects and cannot be stopped without causing rapid climate change. Our simulations suggest that the potential for these types of climate engineering to make up for failed mitigation may be very limited

Large-time behavior of solutions for the one-dimensional infrarelativistic model of a compressible viscous gas with radiation

AbstractIn this paper, assuming suitable hypotheses on the transport coefficients, we prove the large-time behavior, as time tends to infinity, of solutions in Hi=Hi×H0i×Hi×Hi+1 (i=1,2) for the one-dimensional infrarelativistic model of a compressible viscous gas with radiation

Modeling assessments of climate engineering

Climate Engineering (CE), defined as the deliberate intervention in the Earth’s climate system in large scale to alleviate global warming, has been discussed as an important option to counter climate change challenges. In this thesis, I conducted five assessments on some specific CE technologies using the University of Victoria Earth System Climate Model (UVic_ESCM). Each individual assessment investigated the climate responses when particular CE technologies were applied under high CO2 emission scenarios from the year 2020 to 2099. The main aim of those assessments is to improve the understanding of CE technologies regarding their global warming offset efficacy, environmental side effects, simulation uncertainties, and extended usages potentially

Geoengineered ocean vertical water exchange can accelerate global deoxygenation

Ocean deoxygenation is a threat to marine ecosystems. We evaluated the potential of two ocean intervention technologies, i.e. “artificial downwelling (AD)” and “artificial upwelling (AU)”, for remedying the expansion of Oxygen Deficient Zones (ODZs). The model‐based assessment simulated AD and AU implementations for 80 years along the eastern Pacific ODZ. When AD was simulated by pumping surface seawater to the 178 ~ 457 m depth range of the ODZ, vertically integrated oxygen increased by up to 4.5% in the deployment region. Pumping water from 457 m depth to the surface (i.e. AU), where it can equilibrate with the atmosphere, increased the vertically integrated oxygen by 1.03%. However, both simulated AD and AU increased biological production via enhanced nutrient supply to the sea surface, resulting in enhanced export production and subsequent aerobic remineralization also outside of the actual implementation region, and an ultimate net decline of global oceanic oxygen

Why does the apparent mass of a coronal mass ejection increase?

Mass is one of the most fundamental parameters characterizing the dynamics of a coronal mass ejection (CME). It has been found that CME apparent mass measured from the brightness enhancement in coronagraph images shows an increasing trend during its evolution in the corona. However, the physics behind it is not clear. Does the apparent mass gain come from the mass outflow from the dimming regions in the low corona, or from the pileup of the solar wind plasma around the CME when it propagates outwards from the Sun? We analyzed the mass evolution of six CME events. Their mass can increase by a factor of 1.6 to 3.2 from 4 to 15 Rs in the field of view (FOV) of the coronagraph on board the Solar Terrestrial Relations Observatory (STEREO). Over the distance about 7 to 15 Rs, where the coronagraph occulting effect can be negligible, the mass can increase by a factor of 1.3 to 1.7. We adopted the `snow-plough' model to calculate the mass contribution of the piled-up solar wind in the height range from about 7 to 15 Rs. For 2/3 of the events, the solar wind pileup is not sufficient to explain the measured mass increase. In the height range from about 7 to 15 Rs, the ratio of the modeled to the measured mass increase is roughly larger than 0.55. Although the ratios are believed to be overestimated, the result gives evidence that the solar wind pileup probably makes a non-negligible contribution to the mass increase. It is not clear yet whether the solar wind pileup is a major contributor to the final mass derived from coronagraph observations. However, our study suggests that the solar wind pileup plays increasingly important role in the mass increase as a CME moves further away from the Sun.Comment: 27 pages, 2 tables, 9 figures, accepted by Ap

Impulsive control of nonlinear systems with impulse time window and bounded gain error

In this paper, we establish a new sufficient condition for the stability of impulsive systems with impulse time window and bounded gain error. The proposed result is more general and more applicable than some existing results. Finally, a numerical example is given to show the effectiveness of our result