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排序方式: 共有426条查询结果,搜索用时 15 毫秒
81.
Strata title was introduced in Australia over 50 years ago and offered a legal mechanism for space to be vertically subdivided and traded. Importantly, it allowed individualised property rights to be applied to multi-unit housing. In New South Wales, recent changes to the Strata Scheme Development Act allow termination of strata schemes with less than unanimous support of owners. A central feature of the discussion surrounding the implementation of these changes was to question the rights associated with ownership of strata. This paper presents findings from key-informant interviews undertaken in the lead up to the reforms to the NSW legislation governing strata termination. Analysis of these interviews demonstrates the complex ways in which property rights are understood in relation to strata termination within the broader context of housing. This paper argues that successful implementation of the new legislation impacting upon property rights in strata will require concerted engagement with wider social concepts and understanding of housing within the Australian community. 相似文献
82.
Relocating Disadvantage in Five Australian Cities: Socio-spatial Polarisation under Neo-liberalism 总被引:2,自引:0,他引:2
During the mid-1980s, the Australian political discourse shifted decisively towards a neo-liberal political agenda that has remained the dominant policy paradigm ever since. Arguably, a key outcome of this has been an increase in social inequality. However, there has been little acknowledgement of this process in Australian urban policy debates. Yet these social outcomes have been accompanied by distinctive impacts on the socio-spatial structure of the Australian city. Using Census data over a 25 year period between 1986 and 2011, this paper analyses the trend towards a marked suburbanisation of the most disadvantaged households in the five major Australian cities. Its conclusions have relevance for current metropolitan planning strategies and their capacity to address what is emerging as Australia’s version of the now more widely recognised “urban inversion” of the last quarter of a century. 相似文献
83.
A series of centrifuge model tests of the lateral response of a fixed-head single pile in soft clay is reported. Both monotonic and cyclic episodes of loading are described, with varying amplitude and with intervening periods of reconsolidation. The soil conditions are characterized by cyclic T-bar penetrometer tests. The ultimate capacity under monotonic load for virgin and for postcyclic conditions was found to be comparable with calculations based on existing design methods, including theoretical plasticity solutions and empirical methods. The lateral stiffness was observed to degrade with cycles, with the rate of degradation being greater for larger cycles. The degradation pattern has been tentatively linked to the cyclic T-bar response, by considering the ‘damage’ associated with the cumulative displacement and remolding, in each case. This approach provides a consistent interpretation of the tests. Although episodes of pile movement and soil remolding led to a reduction in lateral resistance, intervening periods of reconsolidation led to a similar magnitude of recovery and a reduction in the level of softening in subsequent cyclic episodes. During an initial episode of cyclic lateral movement, the stiffness degraded by a factor of 2.3, which is comparable with the strength sensitivity derived from a cyclic T-bar test. In contrast, after five episodes of reconsolidation, the stiffness had recovered back to within 25% of the stiffness observed in the first cycle of the first episode, and it showed negligible degradation during subsequent cycling. This observation implies that, over a long period of cyclic loading, the lateral stiffness of a pile may tend towards a value that is independent of cycle number, and that represents a balance between the damaging effects of remolding and pore pressure generation and the healing effects of time and reconsolidation. 相似文献
84.
Azin M Guggenmos DJ Barbay S Nudo RJ Mohseni P 《IEEE transactions on bio-medical engineering》2011,58(9):2589-2597
This paper reports on a miniaturized system for spike-triggered intracortical microstimulation (ICMS) in an ambulatory rat. The head-mounted microdevice comprises a previously developed application-specific integrated circuit fabricated in 0.35-μm two-poly four-metal complementary metal-oxide-semiconductor technology, which is assembled and packaged on a miniature rigid-flex substrate together with a few external components for programming, supply regulation, and wireless operation. The microdevice operates autonomously from a single 1.55-V battery, measures 3.6 cm × 1.3 cm × 0.6 cm, weighs 1.7 g (including the battery), and is capable of stimulating as well as recording the neural response to ICMS in biological experiments with anesthetized laboratory rats. Moreover, it has been interfaced with silicon microelectrodes chronically implanted in the cerebral cortex of an ambulatory rat and successfully delivers electrical stimuli to the second somatosensory area when triggered by neural activity from the rostral forelimb area with a user-adjustable spike-stimulus time delay. The spike-triggered ICMS is further shown to modulate the neuronal firing rate, indicating that it is physiologically effective. 相似文献
85.
The effectiveness of a stimulus as a conditioned reinforcer depends on the temporal context of reinforcement, that is, the overall rate of reinforcement in the situation. The dominant view has been that context determines the learned value of a stimulus directly, according to delay-reduction theory. By contrast, the contextual choice model (CCM) maintains that value is independent of context and incorporates the effects of context on choice in the framework of the matching law. The authors report 2 experiments with pigeons as subjects that use transfer tests to assess the value of stimuli in the concurrent-chains procedure. Results strongly support the assumption of CCM that pigeons learn the temporal relations between events independently of context but that context modulates the expression of that learning as choice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
M. D. Richardson C. D. O’Loughlin M. F. Randolph C. Gaudin 《Canadian Metallurgical Quarterly》2009,135(4):487-496
This paper describes a series of centrifuge model tests designed to assess the increase in capacity of dynamic anchors due to setup in normally consolidated clay. The tests involved measurement of the vertical capacity of 1:200 reduced scale model anchors following various periods of postinstallation consolidation. The short-term capacity was shown to be dependent on the anchor impact velocity. Cavity expansion solutions for consolidation around a solid driven pile were found to provide agreement with the experimental results. A simplified capacity calculation technique predicted higher friction ratio values than is typically observed for driven piles; however, these calculations were complicated by the unusual dynamic anchor load–displacement response and uncertainty regarding the true sample shear strength. Dynamic anchor consolidation proceeds at a slower rate than for suction caissons and open-ended piles of similar equivalent diameter. However, the results indicate that depending on the site conditions, dynamically installed anchors remain a viable alternative to conventional deep-water mooring techniques. 相似文献
87.
Loss in Anchor Embedment during Plate Anchor Keying in Clay 总被引:2,自引:0,他引:2
Zhenhe Song Yuxia Hu Conleth O’Loughlin Mark F. Randolph 《Canadian Metallurgical Quarterly》2009,135(10):1475-1485
Vertically installed plate anchors have been investigated in this paper by numerical analysis and centrifuge modeling. In the numerical analysis, the large deformation finite-element method (remeshing and interpolation technique with small strain) was used to simulate strip plate anchor rotation. In the centrifuge model tests, transparent soils were used to observe square anchor rotation. The loss in anchor embedment during anchor keying was assessed for anchors in uniform and normally consolidated soils with anchor pullout angle varying from 30° to 90° to the horizontal. It was found that the loss in anchor embedment during anchor keying may be expressed in terms of a nondimensional anchor geometry factor, which is a function of the eccentricity of the padeye, angle of loading, and the net moment applied to the anchor at the stage where the applied load balances the anchor weight. However, once the anchor geometry factor reaches a certain value, the loss in anchor embedment stabilizes at 0.25–0.5 times the anchor width. The loss in anchor embedment decreases linearly with decreasing pullout angle. Simple formulae and design procedures have been proposed to estimate the loss in anchor embedment during keying. 相似文献
88.
89.
90.
NC Watson YM Di MS Orr FA Fornari JK Randolph KJ Magnet PT Jain DA Gewirtz 《Canadian Metallurgical Quarterly》1997,72(5):547-559
PURPOSE: To determine the capacity of ionizing radiation to inhibit proliferation, to suppress c-myc expression and to induce apoptotic cell death in the p53 wild-type MCF-7 cell line and the p53 mutated MDA-MB231 cell line. MATERIALS AND METHODS: Growth inhibition and cell killing were determined by cell number and trypan blue exclusion. Apoptosis was assessed through cell morphology and fluorescent end-labelling. c-myc expression was monitored by Northern blotting. RESULTS: Inhibition of cell proliferation by ionizing radiation was similar in both cell lines. MDA-MB231 cells accumulated in G2 while MCF-7 cells accumulated in both the G1 and G2 phases of the cell cycle after irradiation. There was no evidence of apoptosis in either cell line. In MCF-7 cells, growth inhibition correlated closely with an early dose-dependent suppression of c-myc expression; in MDA-MB231 cells, there was no correspondence between growth inhibition and a transient, dose-independent reduction in c-myc message. CONCLUSIONS: These findings suggest that in the absence of classical apoptotic cell death, radiosensitivity is not predictably related to the p53 status of the cell. While both p53 and c-myc may be linked to the DNA damage response pathway, neither p53 nor c-myc are essential for growth arrest in response to ionizing radiation. 相似文献