ON THE EARTHQUAKE RESPONSE OF ROTORS

In this paper, the influence of the rotation speed on the earthquake response of rotors is investigated by means of a simple model with only two degrees of freedom. Some worth noticing properties of the eigenmodes and the transfer functions in the presence of solid gyroscopic effect are discussed. In particular, the importance of the relative contribution of the forward and backward modes is evaluated using basic properties of the transfer functions. In the case of a white noise excitation the backward mode contribution dominates the response, for high values of spin velocity. Depending on the frequency content of the excitation and the rotation speed, an important amplification of the response may occur due to gyroscopic effects, as a result of the amplification of the backward mode response. Nonlinear boundary conditions reduce, to some degree, the differences between the responses of rotating and non-rotating systems, but, even in this case, the importance of the contribution of the backward mode in the response appears clearly. Rotors immersed in a dense fluid with moderate confinement exhibit different behaviour and amplification is possible in the case of resonant response of the second forward mode.     

NEIGHBORHOOD SOCIAL MIX AND ADULTS' INCOME TRAJECTORIES: LONGITUDINAL EVIDENCE FROM STOCKHOLM

We investigate the relationship between neighborhood income composition and income trajectories of adults, employing annual panel data from Stockholm over the 1991–2008 period and multiple measures of neighborhood income mix. We advance the human geography literature in three ways by quantifying neighborhood effects that: (1) are unusually precise due to our large sample size; (2) are arguably causal and unbiased due to the econometric techniques employed; (3) are potentially heterogeneous, varying according to gender, income group, and ethnicity. Our innovative, fixed‐effect change modeling indicates that neighborhood income mix affects subsequent one‐ and five‐year income trajectories of residents in highly heterogeneous ways according to gender, income and ethnicity, and for some groups this effect is substantial. The evidence supports on Pareto improvement grounds a social mix policy that attempts to reduce the incidence of lower‐income dominant neighborhood environments and replace them with more mixed or middle‐income dominant ones.     

Migration motives of gay men in the new acceptance era: a cohort study from Malmö, Sweden

Greater diversity in life courses has become both possible and real in the twenty-first century, affecting the relocation behaviours of individuals. Therefore, it is logical that the relocation patterns of minorities have been receiving increasing attention. In particular, the migration patterns of gay men have been studied, with a focus on the embodied reasons for mobility. This downsized analysis has shown the importance of identity building and identity search. However, this article argues that analysis of migration among gay men also needs to be upsized. This study aims to show how both context and embodiment has affected the mobility of gay men. Through a case study within the context of a strong welfare state (Sweden) that adopted sexual equality early, gay men’s motives for migration are studied. The results suggest that the migration patterns of gay men are becoming more similar to those of the general population. This finding shows that current conceptualisations of the migration patterns of gay men can be advanced by acknowledging contextual effects. The integration of a downsized and an upsized understanding also offers the possibility of moving beyond the identity specifics showing that populations are becoming increasingly diverse and homogeneous simultaneously.     

Regional polycentricity: an indicator framework for assessing cohesion impacts of railway infrastructures

Territorial cohesion has become one of the main objectives in transport planning. This has fostered the development of assessment methodologies to quantitatively estimate the territorial impact of major transport infrastructures, which are particularly scarce at the intra-regional level. Linked to cohesion, polycentricity has been defined as the best spatial configuration to achieve balanced regions where population and opportunities are distributed among several entities linked by functional relationships. This paper aims to present a methodology to estimate these impacts based on the use of a new regional composite polycentricity indicator. The proposed indicator is tested by comparing the effects of conventional and high-speed railway (HSR) alternatives in the territorial system of a northern region of Spain. This quantitative assessment is a ranking tool for prioritizing rail network alternatives in terms of achieving the most balanced territory, which is especially relevant in countries where HSR networks follow cohesion goals. Our results show that new HSR links should only be complementary to regional railway services, and that the suppression of secondary lines should be avoided if a reduction in polarization is to be achieved.     

Soft Transport Policies and Ground‐Level Ozone: An Evaluation of the “Clear the Air Challenge” in Salt Lake City

In recent years, communities have begun to implement both “soft” and mandatory policies designed to address worsening air quality. Voluntary or soft transportation policies have included air quality alert systems that encourage people not to drive on days when the air quality index is above a specified threshold and public education/action campaigns that focus on reducing automobile related travel. In this article, we evaluate the effectiveness of one such soft policy, the Clear the Air Challenge (CAC), in reducing ground‐level ozone during the Wasatch Front's summer ozone season. Using daily ozone data and color‐coded daily air quality designations from 2006 through 2012, we estimate a range of nonequivalent control group models. In only one of the models does the CAC generate a statistically significant but small reduction in ground‐level ozone. Future research should assess the full range of costs and benefits to the public associated with such soft transport policies.     

The dynamics of global visual effects and games development industries: lessons for Australia’s creative industries development policy

The paper critiques the focus of creative industries policy on capability development of small and medium sized firms and the provision of regional incentives. It analyses factors affecting the competitiveness and sustainability of the games development industry and visual effects suppliers to feature films. Interviews with participants in these industries highlight the need for policy instruments to take into consideration the structure and organization of global markets and the power of lead multinational corporations. We show that although forms of economic governance in these industries may allow sustainable value capture, they are interrupted by bottlenecks in which ferocious competition among suppliers is confronted by comparatively little competition among the lead firms. We argue that current approaches to creative industries policy aimed at building self-sustaining creative industries are unlikely to be sufficient because of the globalized nature of the industries. Rather, we argue that a more profitable approach is likely to require supporting diversification of the industries as ‘feeders’ into other areas of the economy.     

环南海区域16个典型沿海城市的用地空间增长规律研究

本文选取中国和东南亚十个国家16个人口 30万以上城市作为研究对象,采用1990年、2000年、2010年和2018年4期城市建成用地数据,应用城市土地密度函数和公共边测度方法,计算各时段城市空间增长速率以及用地扩张模式,并简要探讨城市空间扩张与人口、产业之间的关系.主要结论为:①1990-2018年间,广州、万象等城...     

企业主义视角下大城市保障房建设的策略选择及其社会空间后果

城市企业主义是理解地方政府行为与城市空间变迁的重要政治经济视角,在中国推进经济全球化和住房市场化的背景下,企业化的地方政府,特别是大城市政府,在保障房的建设实践中往往采取偏向性的策略选择。本文着重讨论企业主义视角下大城市政府保障房建设的策略选择及其社会空间后果。研究发现,大城市政府主要通过实施保障房政策的异化和保障房住区的边远化策略,来履行其住房保障职责。然而,这种选择性策略带来的直接的社会空间后果是低收入群体的边缘化,具体表现为外来务工人员等在保障政策上的边缘化,以及保障房居民在社会空间上的边缘化。文章进一步指出,保障房应回归其保障本位,以满足低收入群体的真实需求。     

国外区域经济研究的一个新趋势——区域经济网络研究

现代区域经济发展呈现出网络化的趋势。国外区域经济学者将复杂网络理论和方法引入到区域经济学中,逐渐开拓出区域经济网络研究这个新领域,形成了解释区域经济现象和揭示区域经济规律的网络分析路径。目前,国外的研究工作主要是运用复杂网络理论和分析方法,对区域经济中的各类网络进行规范的定义和描述,研究这些网络的形成与演化,揭示区域经济增长和发展中的网络效应,分析知识、技术等要素在网络中的流动和扩散。