Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show tha...Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show that mussels can accumulate Cd through seawater, food, sediment and suspended particle pathways in a short period of time. Mussels' uptake of Cd through the seawater pathway reaches the highest concentration approximately 3 and 9 times larger than through the algae and sediment pathways respectively after 7 d. This indicates that the Cd-accumulation through seawater is most efficient. Results also indicate that the uptake directly through contaminated algae, particles or sediments ingested by mussels is less important when compared with the uptake of Cd by mussels through the seawater pathway. Metal uptake pathways and mechanisms of bioaccumulation by marine bivalve are also discussed in this paper.展开更多
The cumulative prospect theory(CPT) is applied to study travelers' route choice behavior in a degradable transport network. A cumulative prospect theory-based user equilibrium(CPT-UE) model considering stochastic ...The cumulative prospect theory(CPT) is applied to study travelers' route choice behavior in a degradable transport network. A cumulative prospect theory-based user equilibrium(CPT-UE) model considering stochastic perception error(SPE) within travelers' route choice decision process is developed. The SPE is conditionally dependent on the actual travel time distribution, which is different from the deterministic perception error used in the traditional logit-based stochastic user equilibrium. The CPT-UE model is formulated as a variational inequality problem and solved by a heuristic solution algorithm. Numerical examples are provided to illustrate the application of the proposed model and efficiency of the solution algorithm. The effects of SPE on the reference point determination, cumulative prospect value estimation, route choice decision and network performance evaluation are investigated.展开更多
A series of biaxial two-level variable amplitude loading tests are conducted on smooth tubular specimens of LY12CZ alumin- ium alloy. The loading paths of 90° out-of-phase, 45° out-of-phase and 45° in-p...A series of biaxial two-level variable amplitude loading tests are conducted on smooth tubular specimens of LY12CZ alumin- ium alloy. The loading paths of 90° out-of-phase, 45° out-of-phase and 45° in-phase are utilized. The fatigue damage cumulative rules under two-level step loading of three loading paths are analyzed. By introducing a parameter a which is a function of the phase lag angle between the axial and the torsional loading, a new multiaxial nonlinear fatigue damage cumulative model is proposed. The proposed model is evaluated by the experimental aluminium alloy, and multi-level loading of 45 steel. Fatigue lives data for two-level loading, multi-level loading of LY12CZ predicted are within a factor of 2 scatter band.展开更多
Primitive accumulation refers to during industrialization. This article argues that the early phase of development this Marxist concept implicates a deeper notion of injustice, which contains logic of linearity that c...Primitive accumulation refers to during industrialization. This article argues that the early phase of development this Marxist concept implicates a deeper notion of injustice, which contains logic of linearity that can be further dissected into a trichotomous part worthy of our discussion, namely, temporal ordering, harsh treatment, and inhumane consequences. This "linearity" as assumed in this concept, nevertheless, was not unchallenged in history. As a matter of fact, in Mao's era, China deliberately sought an alternative path to the capitalist mode by attending to social welfare, physical well-being and rights protection for workers. This part of history is well worth re-investigation and re-interpretation.展开更多
文摘Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show that mussels can accumulate Cd through seawater, food, sediment and suspended particle pathways in a short period of time. Mussels' uptake of Cd through the seawater pathway reaches the highest concentration approximately 3 and 9 times larger than through the algae and sediment pathways respectively after 7 d. This indicates that the Cd-accumulation through seawater is most efficient. Results also indicate that the uptake directly through contaminated algae, particles or sediments ingested by mussels is less important when compared with the uptake of Cd by mussels through the seawater pathway. Metal uptake pathways and mechanisms of bioaccumulation by marine bivalve are also discussed in this paper.
基金Project(2012CB725400)supported by the National Basic Research Program of ChinaProjects(71271023,71322102)supported by the National Science Foundation of ChinaProject(2015JBM053)supported by the Fundamental Research Funds for the Central Universities,China
文摘The cumulative prospect theory(CPT) is applied to study travelers' route choice behavior in a degradable transport network. A cumulative prospect theory-based user equilibrium(CPT-UE) model considering stochastic perception error(SPE) within travelers' route choice decision process is developed. The SPE is conditionally dependent on the actual travel time distribution, which is different from the deterministic perception error used in the traditional logit-based stochastic user equilibrium. The CPT-UE model is formulated as a variational inequality problem and solved by a heuristic solution algorithm. Numerical examples are provided to illustrate the application of the proposed model and efficiency of the solution algorithm. The effects of SPE on the reference point determination, cumulative prospect value estimation, route choice decision and network performance evaluation are investigated.
基金supported by the National Natural Science Foundation of China(Grant No.10702027)Aviation Science Funds of China(Grant No.2011ZA52016)Program for Changjiang Scholars and Innovative Research Team in University(Grant No.Irt0906)
文摘A series of biaxial two-level variable amplitude loading tests are conducted on smooth tubular specimens of LY12CZ alumin- ium alloy. The loading paths of 90° out-of-phase, 45° out-of-phase and 45° in-phase are utilized. The fatigue damage cumulative rules under two-level step loading of three loading paths are analyzed. By introducing a parameter a which is a function of the phase lag angle between the axial and the torsional loading, a new multiaxial nonlinear fatigue damage cumulative model is proposed. The proposed model is evaluated by the experimental aluminium alloy, and multi-level loading of 45 steel. Fatigue lives data for two-level loading, multi-level loading of LY12CZ predicted are within a factor of 2 scatter band.
文摘Primitive accumulation refers to during industrialization. This article argues that the early phase of development this Marxist concept implicates a deeper notion of injustice, which contains logic of linearity that can be further dissected into a trichotomous part worthy of our discussion, namely, temporal ordering, harsh treatment, and inhumane consequences. This "linearity" as assumed in this concept, nevertheless, was not unchallenged in history. As a matter of fact, in Mao's era, China deliberately sought an alternative path to the capitalist mode by attending to social welfare, physical well-being and rights protection for workers. This part of history is well worth re-investigation and re-interpretation.