基于改进遗传算法投影寻踪的大城市郊区耕地安全综合评价

针对耕地安全高维评价体系指标权重难以赋值、客观性差的问题,构建了实码加速的遗传算法投影寻踪（RAGA-PP）模型,对快速城市化的大城市郊区耕地安全进行综合评价。以广州城市发展的南拓与北优两个郊区——番禺区与从化市为例,建立4个子系统共32个指标的耕地安全评价指标体系,对大城市郊区耕地的数量结构安全、质量安全、经济社会安全和生态安全进行综合评价。结果表明:（1）RAGA-PP模型在多目标、多因素的耕地安全综合评价中取得了满意的效果;（2）广州市郊区耕地安全评价的影响因子权重在远郊区和近郊区存在较大差别,开展不同区域对比研究更适合采用总投影方向确定的权重值。（3）由于近郊区与远郊区发展定位与发展战略迥异,城市化进程速度不同,区域耕地安全等级差别较大,近郊的番禺区耕地综合安全水平低于远郊的从化市,其中番禺区仅耕地经济社会安全水平高于从化市,而耕地的质量安全、数量安全和生态安全方面均低于从化市。     

Style Wars: revolution in the suburbs?

Is there a revolution occurring in the Australian suburb? From a brief examination of demographic, economic, political and aesthetic changes, it appears that the suburbs of the new century are very different from those of the last. With the demise of key underpinnings of the older suburban form—the sexual division of labour, particular family forms, localised communities and bucolic private gardens—has gone an end to official support of the expansive suburb and a major shift in their politics, planning, economies and relationship to the CBD and other centres. With falling household sizes has gone a seemingly contradictory trend toward larger houses on smaller blocks of land. In the context of these many changes along with urban containment and consolidation, this paper argues that there is a convergence occurring between the design of inner, middle and outer suburban dwellings. The negativity long heaped upon the suburban bungalow by the custodians of taste is being revisited. The style wars are easing, as suburban homes increasingly resemble those appearing in densified cities across the nation.     

Prosperity and the Suburban Dream: Quality of life and affordability in western Sydney

Over the past 10 years Sydney has experienced a remarkable wave of economic prosperity and growth, partly due to its developing role as a regionally significant global city. Through this period, maintaining the quality of life in the city has been regarded as particularly important. Yet traditional accounts of the global city have stressed quality-of-life features of the inner city. In this paper I examine the implications of the prosperity of global Sydney for the quality of life of western Sydney, paying particular attention to environmental amenity and the affordability of housing. The paper argues, first, that growth in the Sydney region has depended upon continued growth in western Sydney. It highlights key instances in which residents have resisted developments associated with this growth and regarded as major threats to the environmental amenity of the region. Second, the paper argues that the prosperity of Sydney, combined with changes to government policy, have impacted upon the supply of affordable rental housing in western Sydney. This is particularly significant in the case of public housing. Managing growth in the city will require attention to managing quality-of-life issues in the metropolis as a whole.