一种复杂载荷作用下船舶结构疲劳裂纹扩展预报方法

风暴模型是Tomita等提出的用来评估船舶结构疲劳强度的一种随机波浪载荷简化模型,它能表达波浪载荷是与时间相关的随机过程。文中介绍了风暴模型及波浪诱导应力短期分布的基本特征。将风暴模型和裂纹扩展率单一曲线模型及焊趾表面裂纹应力强度因子的计算方法结合起来,探讨了复杂载荷作用下船舶结构疲劳裂纹扩展预报方法。并用权函数法计算了给定残余应力分布的表面裂纹应力强度因子。预报了对接焊接接头焊趾处表面裂纹在风暴波浪载荷作用下的疲劳裂纹扩展行为,结果表明风暴的大小、顺序,初始裂纹尺寸及残余应力对裂纹扩展行为影响明显。合理的风暴模型参数及初始裂纹尺寸的确定对船舶结构的疲劳寿命预报是非常重要的。     

可靠性增长设计技术

介绍可靠性增长设计技术，包括可靠性增长方法、试验、计划与评估。     

十一五规划与中国经济增长模式的转变

经济学和学术界经过近两年的争论和研讨，已经就经济增长方式和工业化道路达成共识，即现代经济增长不再主要依靠投资拉动而是靠科学技术以及与此相关的生产型服务业发展。十一五规划提出要加快推进从粗放增长到集约增长的转变，规定的战略重点及主要措施有：1．加强自主创新能力；2．发展先进制造业，推进工业结构的优化升级；3．加快发展服务业，特别是生产型服务业；4．积极推进城市化的同时，稳步推进新农村的建设，建设社会主义新农村。笔者强调，要实现十一五规划，制度重于技术，关键在于改革，而关键的关键，则在于政府职能的转变。     

家族企业路在何方——关于加快我国家族企业向现代企业转变的法律思考

改革开放以来,我国私营经济获得了长足的发展,并为我国经济和社会发展做出了重要贡献,成为社会主义市场经济的重要组成部分。但随着市场外在条件和社会经济发展格局的变化,作为私营资本形式之一的家族企业,其自身的不适应性逐步凸现出来。克服家族式管理的不足,转换管理机制和管理方式,通过法律制度和资本市场的完善使家族企业完成由家庭化向专业化、由宗法化向市场化的转变,主动改造企业的产权结构和治理结构,实现家族企业制度向现代企业制度的转型,是使其真正做大做强的必由之路。     

Effects of small-scale turbulence on the growth of two diatoms of different size in a phosphorus-limited medium

The effect of turbulence on the nutrient flux towards osmotrophic cells is predicted to be size dependent. This should translate into growth. We experimentally followed and modelled the growth of two marine diatoms of different size (Thalassiosira pseudonana, 6 μm in diameter and Coscinodiscus sp., ca. 109 μm in diameter) under still water and turbulent conditions, using a shaker table. Experiments were done with phosphorus-limited cultures and lasted for ca. 5 days. Turbulence enhanced the growth of Coscinodiscus sp. in agreement with theory but not the growth of T. pseudonana, which was actually slightly lower under turbulence. At the end of the experiments there were about 1.7 times as many Coscinodiscus sp. cells in the turbulent treatment than in the still treatment, while for T. pseudonana almost the same cell concentration was found in both conditions. In addition, the Coscinodiscus sp. cells growing under still conditions presented a higher specific alkaline phosphatase activity than those growing in turbulence which indicates a higher need for phosphorus in the still cultures. A simple dynamic model, based on Michaelis–Menten nutrient uptake kinetics, needed nearly no optimisation other than using observed initial conditions of phosphate and cell concentrations. The model showed how an increased nutrient flux towards the cells translates non-linearly into cell growth, most likely by affecting the half-saturation constant (K_M). However, since Coscinodiscus sp. experienced significant mortality and cells partially settled to the bottom of the containers, unequivocal support for the size-dependent effect of turbulence on nutrient uptake will require further experiments and more sophisticated modelling. The mechanisms to connect an increased nutrient flux towards cells with population growth and whether this process is size dependent are important in parameterizing the effects of turbulence on marine plankton in coupled physical–biological models.     

瘢痕增生机理的研究

增生性瘢痕（HS）和瘢痕疙瘩（K）临床表现明显不同，为探讨瘢痕增生的机理，对17例K、55例HS及55例正常皮肤（NS）标本采用actin、bFGF及其受体flg抗体免疫组化半定量分析，结合组织学淋巴细胞、皮肤附件变化情况的动态观察。结果：K和HS早期均有许多炎性细胞浸润在残留的皮肤附件和闭塞的毛细血管周围，随着瘢痕增生，皮肤附件、淋巴细胞和毛细血管逐渐减少，但在K组滞留的时间和数量远较HS组多。bFGF和flg在三组的成纤维细胞、血管内皮细胞、单核细胞和附件上皮细胞均有表达，强度依次为：K＞HS＞NS（P＜0.01），而K组flg表达明显强于bFGF。结论：组织中残留的皮肤附件、浸润的淋巴细胞和增生的毛细血管三者互为消长，由此，促进了成纤维细胞增殖和胶原沉积，K对flg敏感性增加，可能是其侵袭性生长的重要因素。     

Growing patronage - Challenges and what has been found to work

This paper synthesizes evidence on growing public transport patronage. The paper firstly examines barriers to patronage growth before reviewing evidence on endogenous factors (those within the control of operators and regulators) and exogenous factors (those factors such as socio-economic influences which are not controlled by regulators/operators) which affect public transport patronage. Suggested barriers include capacity, network transfers, perceptions and investment/subsidy needs. Evidence is presented suggesting that reliability, service levels and fares are the principal tools to adopt in growing patronage. Car ownership, income and population growth, employment and urban sprawl are amongst the exogenous factors identified as influencing patronage.     

地铁联络线建设成本优化法的0-1规划模型

地铁联络线合理布局既是城市轨道交通线网规划的重要组成部分,又是提高线路通过能力的必要保证。通过对联络线的重要性以及建设成本优化法的基本思路和寻优过程进行分析,找出了该方法的不足,建立0-1规划模型,并用lingo编程实现最优化;最后得到一般情况下该问题的数学模型。     

军队院校学员可持续成长能力的灰色系统评价*

根据军队院校对干部学员的知识、能力、素质要求及标准，设计了可持续成长能力的评价指标体系，并结合多层次灰色系统评价模型，利用数学原理，对其可持续成长能力进行了科学合理的评估和比较。该评价模型较好将理论和实践相结合，解决了干部学员发展潜力的评估和比较问题，为其它政治军事工作的开展提供了依据。