A suitable pH value of the slurry is a key to efficient mineral flotation. Considering the control delay problem of pH value caused by offline pH measurement, an integrated prediction model for pH value in bauxite fro...A suitable pH value of the slurry is a key to efficient mineral flotation. Considering the control delay problem of pH value caused by offline pH measurement, an integrated prediction model for pH value in bauxite froth flotation is proposed, which considers the effect of ore compositions on pH value. Firstly, a regression model is obtained for alkali(Na_2CO_3) consumed by the reaction between ore and alkali. According to the first-order hydrolysis of the remaining alkali, a mechanism-based prediction model is presented for the pH value. Then, considering the complexity of the flotation mechanism, an error prediction model which uses time series of the error of the mechanism model as inputs is presented based on autoregressive moving average(ARMA) method to compensate the mechanism model. Finally, expert rules are established to correct the error compensation direction, which could reflect the dynamic changes during the process accurately and effectively. Simulation results using industrial data show that the presented model meets the needs of the industrial process, which laid the foundation for predictive control of pH regulator.展开更多
Vessel-source marine oil pollution damage is governed by an international liability regime, including the CLC treaties, 2001 Bunker Convention and the 1977 Seabed Convention. Despite that ＂pollution damage＂ in these...Vessel-source marine oil pollution damage is governed by an international liability regime, including the CLC treaties, 2001 Bunker Convention and the 1977 Seabed Convention. Despite that ＂pollution damage＂ in these treaties does not exclude damage to marine biodiversity, the fact that damage to marine biodiversity is not mentioned in this regime arouses the question of compensability of damage to marine biodiversity under the regime. This article attempts to investigate this question from the perspectives of the relationship between marine environmental damage and damage to marine biodiversity and the possibility of compensation for damage to marine biodiversity under the regime. While the findings of this article reveal that the regime cannot provide sufficient compensation for such damage, this article in the conclusion offers some suggestions for the sake of remedying of damaged marine biodiversity under the regime.展开更多
Offshore oil and gas exploration and production comes with risk of release of hydrocarbons in to sea. Today, the probability of such an event is relatively low, but the consequences are nevertheless significant and ca...Offshore oil and gas exploration and production comes with risk of release of hydrocarbons in to sea. Today, the probability of such an event is relatively low, but the consequences are nevertheless significant and can cover a vast geographical area. As such, it raises the question as to whether liability and compensation in oil ＆ gas related incidents should be covered under international law. Current international legislation addresses the issue mainly in terms of shipping. This paper attempts to shed light on the topic in relation to oil and gas exploration whilst investigating notable events in the UK and the USA. The findings show that domestic laws of these countries cover the matter sufficiently. However, the question of whether the regulation should fall under international regulation can unfortunately not be answered with confidence as it would require a test-case of a situation where an oil spill affects multiple littoral states.展开更多
Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single...Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plas- ticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes （standing genetic variation, genetic compensation） and two of which do not （standing epigenetic variation, plastic compensation）. Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for under- standing evolutionary change展开更多
基金Supported by the National Natural Science Foundation of China(61673401)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(61621062)the Fundamental Research Funds for the Central Universities of Central South University(2016zzts343)
文摘A suitable pH value of the slurry is a key to efficient mineral flotation. Considering the control delay problem of pH value caused by offline pH measurement, an integrated prediction model for pH value in bauxite froth flotation is proposed, which considers the effect of ore compositions on pH value. Firstly, a regression model is obtained for alkali(Na_2CO_3) consumed by the reaction between ore and alkali. According to the first-order hydrolysis of the remaining alkali, a mechanism-based prediction model is presented for the pH value. Then, considering the complexity of the flotation mechanism, an error prediction model which uses time series of the error of the mechanism model as inputs is presented based on autoregressive moving average(ARMA) method to compensate the mechanism model. Finally, expert rules are established to correct the error compensation direction, which could reflect the dynamic changes during the process accurately and effectively. Simulation results using industrial data show that the presented model meets the needs of the industrial process, which laid the foundation for predictive control of pH regulator.
文摘Vessel-source marine oil pollution damage is governed by an international liability regime, including the CLC treaties, 2001 Bunker Convention and the 1977 Seabed Convention. Despite that ＂pollution damage＂ in these treaties does not exclude damage to marine biodiversity, the fact that damage to marine biodiversity is not mentioned in this regime arouses the question of compensability of damage to marine biodiversity under the regime. This article attempts to investigate this question from the perspectives of the relationship between marine environmental damage and damage to marine biodiversity and the possibility of compensation for damage to marine biodiversity under the regime. While the findings of this article reveal that the regime cannot provide sufficient compensation for such damage, this article in the conclusion offers some suggestions for the sake of remedying of damaged marine biodiversity under the regime.
文摘Offshore oil and gas exploration and production comes with risk of release of hydrocarbons in to sea. Today, the probability of such an event is relatively low, but the consequences are nevertheless significant and can cover a vast geographical area. As such, it raises the question as to whether liability and compensation in oil ＆ gas related incidents should be covered under international law. Current international legislation addresses the issue mainly in terms of shipping. This paper attempts to shed light on the topic in relation to oil and gas exploration whilst investigating notable events in the UK and the USA. The findings show that domestic laws of these countries cover the matter sufficiently. However, the question of whether the regulation should fall under international regulation can unfortunately not be answered with confidence as it would require a test-case of a situation where an oil spill affects multiple littoral states.
文摘Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plas- ticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes （standing genetic variation, genetic compensation） and two of which do not （standing epigenetic variation, plastic compensation）. Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for under- standing evolutionary change
