基于熵权TOPSIS模型的海洋资源环境承载力评价研究——以湛江市为例

为了解和把握湛江市海洋资源环境承载力水平与演变趋势,通过建立包括海洋经济发展、海洋资源承载和海洋环境承载 3 个系统下具体 33 个指标的海洋资源环境承载力评价体系,采用熵权 TOPSIS 模型对湛江市 2007-2016 年这 10 年内海洋资源环境承载力水平及 3 个子系统水平进行动态评价。研究结果表明:湛江市海洋资源环境承载力水平在 2007-2016 年间处于波动起伏的状态,总体水平较高,但仍存在下行的风险。其中,湛江市海洋经济发展水平逐年上升;海洋资源承载水平整体较高,且与海洋资源环境承载力变化趋势较为吻合;海洋环境承载力水平整体呈现较为平稳的趋势。湛江市在制定海洋发展战略规划的同时,应在创新海洋经济发展的基础上,重点向海洋资源保护和海洋生态环境修复倾斜。

Temporal dynamics of nutrient balance, plasma biochemical and immune traits, and liver function in transition dairy cows

The objective of this study was to analyze the dynamics of nutrient balance,physiological biomarkers and comprehensive indexes associated with metabolism and function of organs in transition cows.Fourteen transition cows were used for this research.Dietary intake was recorded daily,and samples of the diet,venous blood and milk were collected for measurements.The balance values of net energy for lactation(NEL),metabolizable protein(MP),and metabolizable glucose(MG) were calculated,and regression analysis and calculation of comprehensive indexes were performed.Accordingly,the prepartum cows presented positive balances of NEL,MP,and MG,while severe negative balances were found during the postpartum period.Dynamic changes of energy metabolism,nutrient mobilization,liver function,anti-oxidative status and immune response,as indicated by blood biomarkers and modified comprehensive indexes,were out of sync with the calculated balance values,but they were closely related to the day relative to calving.Compared with the 21 d prepartum,the plasma concentrations of non-esterified fatty acids(NEFA) and β-hydroxybutyric acid(BHBA) were significantly increased around and after calving(P<0.05),and similar variation tendency was observed for most of other parameters.The occurrence of parturition and the initiation of lactation were more responsible for the negative balances of nutrients in transition dairy cows.Although negative balances of NEL,MP and MG were not observed using the assessment model,the nutritional strategies should be applied before calving,because metabolic adaptations had been validated during the prepartum period.In addition,it was plausible to conclude that the decline of hepatic metabolism,defense function and insulin sensitivity are critical causes of metabolic dysfunction.

颠覆性创新研发联盟网络特征对企业创新绩效的影响研究——制度环境的调节作用

以自动驾驶技术为例,基于资源基础理论与制度基础理论构建企业颠覆性创新研发联盟网络,并探讨其网络特征、制度环境与企业创新绩效的关系。研究结果表明:在颠覆性创新领域,研发联盟中企业的网络密度会对创新绩效产生负向影响,而关系强度对创新绩效具有正向作用;制度环境在颠覆性创新研发联盟网络特征与企业创新绩效中发挥着不同的调节作用,区域创新投入虽然缓解了网络密度对创新绩效的负向影响,但也降低了关系强度对创新绩效的正向作用;知识产权保护不仅能够降低网络密度与创新绩效之间的负向影响,还能够提升关系强度与创新绩效之间的正向作用。

基于政府驱动的区块链产业协同创新演化博弈研究

以有限理性为前提,构建政府驱动下区块链产业协同创新的演化博弈模型,探讨区块链服务企业与学研机构的协同创新策略选择问题,并对要素变动下协同创新策略选择的演化结果进行仿真分析。结果表明:不同状态下的投入成本、额外收益、政府激励、违约金以及收益分配系数等因素对区块链产业的协同创新具有显著影响。对此,从政府政策驱动、企业主体功能与市场体制作用方面提出优化区块链产业协同创新水平的对策建议。