如何促进产业集群发展?——美国亚利桑那州产业集群发展模式分析

1980年代末至1990年代初,美国亚利桑那州经济遭遇严重衰退,地区经济发展面临转型压力。1992年,亚利桑那州实施了产业集群战略,成功推动了地区经济的复苏和转型,并使其成为之后十余年美国经济增长最快的地区之一。通过对亚利桑那州产业集群战略的制定、调整和集群发展特征的深入分析发现,亚利桑那州产业集群的发展得益于科学的战略设计和以"技术密集型中小企业+企业网络组织"为双驱动的发展模式,而政府在这一过程中只扮演着"组织者"和"协调者"的角色。这对中国产业集群的发展具有重要的借鉴意义。     

储层岩石矿物成分对酸蚀裂缝导流能力的影响

储层岩石矿物成分是酸压改造效果影响因素之一。研究认为，在储层岩石矿物成分中易溶物的含量及分布方式决定了酸蚀裂缝导流能力大小，易溶蚀物的含量越多，岩石溶蚀速率越快。室内测试了不同溶蚀速率下的灰岩和白云岩的酸蚀裂缝导流能力，研究了岩石溶蚀速率、易溶蚀物含量对酸蚀裂缝导流能力的影响，对酸压工艺设计方案提出了指导性建议。研究结果表明，储层岩石溶蚀速率与酸蚀裂缝导流能力增加倍比存在抛物线关系，易溶蚀物占30%40% 时酸蚀裂缝导流能力保持较好。     

大数据背景下基于社交网络的聚类随机游走抽样算法研究

数字经济时代,社交网络作为数字化平台经济的重要载体,受到了国内外学者的广泛关注。大数据背景下,社交网络的商业应用价值巨大,但由于其网络规模空前庞大,传统的网络分析方法 因计算成本过高而不再适用。而通过网络抽样算法获取样本网络,再推断整体网络,可节约计算资源, 因此抽样算法的好坏将直接影响社交网络分析结论的准确性。现有社交网络抽样算法存在忽略网络内部拓扑结构、容易陷入局部网络、抽样效率过低等缺陷。为了弥补现有社交网络抽样算法的缺陷,本文结合大数据社交网络的社区特征,提出了一种聚类随机游走抽样算法。该方法首先使用社区聚类算法将原始网络节点进行社区划分,得到多个社区网络,然后分别对每个社区进行随机游走抽样获取样本网 络。数值模拟和案例应用的结果均表明,聚类随机游走抽样算法克服了传统网络抽样算法的缺点,能够在降低网络规模的同时较好地保留原始网络的结构特征。此外,该抽样算法还可以并行运算,有效提升抽样效率,对于大数据背景下大规模社交网络的抽样实践具有重大现实意义。     

The intergenerational education spillovers of pension reform in China

Economic theory establishes that pension privatization weakens the link between old and young and so reduces the incentive to invest in public education in an economy with lower return rate of capital than growth rate of wage. However, empirical studies of the link change are few. In this paper, we investigate the effects of pension privatization and the central government’s subsidy to individual accounts on public education spending in a three-period overlapping generation model. And then, we take contemporary pension reforms in a number of Chinese provinces as offering natural experiment conditions. Using a difference-in-difference framework and 282 municipal districts panel data over years 1998–2009, we test the pension-education theoretical link change. Both our theoretical and empirical results confirm that pension privatization is adversely associated with local public spending on education in China. Private pension subsidies, moreover, magnify this effect. Our study supports the theoretical assertion and selective empirical findings of a negative intergenerational effect of pension privatization.     

乡约的诸属性及其文化原理认识

乡约是传统社会乡民基于一定的地缘和血缘关系,为某种共同目的而设立的生活规则及组织。乡约最初形成于中国,后传播至朝鲜半岛、日本和越南,成为东亚社会共同的法律文化传统。传统中国的乡约有其时空性、价值性和法律性。乡约不是国法,但在乡民的实际生活中发挥着法的作用,是中国传统社会秩序构造链中的重要一环,其内贯一极二元主从式多样化的文化原理,与传统中国社会的结构和文化理念相契合。近代以来,乡约总体上呈现出消解的趋势,但至今仍有各种流变形式,认真对待,合理改造,必有益于中国类型法治社会的建立。     

变态的"他者"--从《沉沦》三部曲中看日本的形象

现代文学史上的著名作家郁达夫留学日本近十载,十年的留学生活使他对日本这个民族有了深刻的了解.本文试图中从其<沉沦>三部曲中窥视郁达夫笔下的日本是怎样在文本中发生了"变态"作一尝试.     

长江三角洲南部下蜀黄土与硬粘土层关系初探

从气候变化和地形影响两个角度 ,对长江三角洲南部晚更新世地层中西部丘陵区的下蜀黄土与东部平原区的硬粘土层进行了初步探讨 ,认为二者的物质来源都是末次冰期盛冰期由风力搬运堆积而形成的。     

关于体育教育专业学生能力培养的研究

通过查阅文献资料和问卷调查反馈,研究分析发现,当前体育教育专业学生能力还不能适应社会发展的需要,且发展不平衡。我们认为,对体育教育专业学生能力的培养应从师德教育、教学表达能力、教学组织能力、教学设计能力、适应教学环境的能力、体育教学自修与改革能力、社会竞争能力等方面下手,使学生的能力在四学年的教学实践活动中,得到有序全面的锻炼和提高、达到最佳培养效果。为他们将来成为合格的、高素质的复合型人才打下坚实的基础。     

Cohabitation and commitment: partnership plans of young men and women

Popular commentators on marriage and the family often interpret the increase in heterosexual couples living together without marrying as reduced willingness to create and honour life‐long partnerships. Survey and in‐depth interviews with samples of 20–29 year olds living in an urban area of Scotland finds little support for the postulated link between growing cohabitation and a weakened sense of commitment to long‐term arrangements. Most of the cohabiting couples strongly stressed their ‘commitment’. Socially acceptable vocabularies of motive undoubtedly influenced answers but interviews helped to explore deeper meanings. Many respondents’ views were consistent with previous research predictions of a weakening sense of any added value of marriage. At the same time, some respondents continued to stress the social significance of the distinction between marriage and cohabitation, consistent with research interpreting cohabitation as a ‘try and see’ strategy part‐way to the perceived full commitment of marriage. The notion that ‘marriage is better for children’ continued to have support among respondents. While, on average, cohabiting couples had lower incomes and poorer employment situations than married couples, only very extreme adverse circumstances were presented as making marriage ‘too risky’. Pregnancy‐provoked cohabitation was not always in this category. Cohabitation was maintained because marriage would ‘make no difference’ or because they ‘had not yet got round to’ marriage. Most respondents were more wary of attempting to schedule or plan in their personal life than in other domains and cohabitees’ attitudes to partnership, including their generally ‘committed’ approach, do not explain the known greater vulnerability of this group to dissolution.