Australia,uranium and nuclear power

The nuclear debate in Australia is shaped by the nation's substantial base of energy resources, including its large reserves of uranium and recent rises in the market price of uranium. But the debate also echoes Australia's past in the development of programs for nuclear weapons. The proposals include uranium enrichment, the storage of nuclear waste in Australia, and the introduction of nuclear reactors. A national inquiry has been instituted by the government. These developments, stemming from a range of factors, have revived the opposition to uranium mining and nuclear power which has for two decades held a dominant role in Australian politics. The issue of what should be Australia's energy path in a time of climate change is beginning to be examined. The importance of the decisions, whether to be a player in the nuclear club with its attendant multiple hazards, or to play a quite different leadership role in the development and adoption of sustainable energy strategies and technologies, cannot be exaggerated.     

Negotiation‐based decision support model for utility relocations in transportation infrastructure projects

Highway projects in metropolitan areas often require that adjacent utilities be relocated to accommodate new or expanded highway facilities. Traditionally, utility owners have been responsible for their own relocations prior to highway construction. However, utility relocation delay was reported as one of the root causes of overall project delays in highway construction. In the USA, one strategic approach sporadically taken over the past 15 years by some state departments of transportation (DOTs) has been to combine utility relocation work with the highway contractor's scope of work. While the combined strategy offers many benefits, it does have its own set of challenges and disadvantages. Many of these difficulties involve disagreements between DOTs and utility owners over the appropriateness of the combined strategy for particular types of relocations. Hence, a negotiation‐based decision support model (DSM) for determining whether to use the combined strategy was developed to provide guidance to both DOTs and utility decision makers during the planning and design phases of highways. A literature review and interviews with experts from both DOTs and the utility industry were conducted to identify significant factors as well as their impact levels on the decision. A DSM aiming at synthesizing the factors and orchestrating the negotiation process for the decision was proposed and verified. As suggested by the model evaluators, the proposed DSM can improve the quality of this complex decision‐making process, especially for less experienced project managers or designers.     

Modelling the dynamics of design error induced rework in construction

Rework that is experienced in construction projects is often caused by errors made during the design process. Factors that contribute to design errors are identified and used to design and develop a systems dynamics model, which is used to simulate a number of practical scenarios that can be used to reduce design errors and rework. The model presented in this paper can enable design and project managers to understand better the process of design documentation and how design errors occur in construction projects.     

Urbanization Effect on Floristic and Landscape Patterns of Green Spaces

The study explored the effects of intensive urbanization on urban plant diversity and landscape pattern. An inventory of plant species in managed green spaces in the nine urban districts of Guangzhou (south China) with varied development history was conducted. The relationships among species richness, diversity and urban development were analysed by community ecology attributes, cluster analysis, growth-form differentiation and district fidelity indices, and statistical tests. The 1055 vascular species were dominated by a small number of common evergreen species, accompanied by many rare species. By species richness, tree was the dominant growth form, followed by herb and shrub. Species richness and diversity were slightly below urban-fringe secondary forests. Old and young districts offered disparate conditions for species enrichment to establish urban landscape patterns with divergent floristic and growth-form assemblages. Urban species profile and vegetation landscapes were mainly influenced by planning and management of the urban landscape and changing landscape fashion.     

Alkaline Hydration Of C2S and C3S

This study analyzed the behavior of two laboratory‐synthesized calcium silicates, C₃S and C₂S, after hydration in 8‐M NaOH and in water as a control. Two‐ and 28‐d mechanical strength values were determined and the products were characterized with XRD, TEM, and ²⁹Si and ²³Na MAS NMR. The results showed that hydrating C₃S in a highly alkaline medium had no significant effect on the mechanical development of the material, whereas in C₂S hydration, that medium hastened hydration substantially, impacting setting and hardening times. This finding has technological implications, given the low early‐age reactivity of dicalcium silicate under normal hydration conditions.     

Hydrodynamics of pulsed spouted beds: Effects of pulsation waveform,amplitude, and frequency

The effect of flow pulsations is studied via a discrete element model on hydrodynamics of spouted bed, which is being used in many important industries like drying processes. Decreased horizontal air percolation and preserving upward momentum, increased particle circulation, increased particle traverse distance, and better homogeneity are resulted from flow pulsations in spouted beds. Among the waveforms studied, square and triangular waveforms differ most and least from steady spouting, respectively. The predictions indicate that the pulsed spouted bed has the potential to enhance both gas and particle motion, hence being useful in drying and other operations.     

增进城市地区生物多样性——以新加坡模式为例

自 1963 年以来,新加坡开展实施了绿化计划,并经历了从“花园城市”到“花园中的亲生态城市”的演变。为了在新加坡实现生物多样性保护,国家公园局制定了自然保护蓝图,重点介绍该规划实施的关键是利用技术创新。新加坡城市生物多样性指数是一种评价生物多样性成效的自我评估工具,已在全球范围内的多个城市得到应用。     

Electroactive behavior assessment of poly(acrylic acid)‐graphene oxide composite hydrogel in the detection of cadmium

Super absorbent polymers of acrylic acid‐graphene oxide (PAA‐GO) were synthesized with different percentage of chemical neutralization (0, 10, and 20%) of the acrylic acid monomer before its polymerization. The influence of their swelling and adsorption/desorption capacity of cadmium ions in aqueous solutions were studied and revealed that the GO enables greater mechanical stability in the materials. The PAA hydrogels, with the same degrees of neutralization, were also prepared without GO to compare with the composites. Additionally, carbon paste electrodes (CPE) modified with the composites PAA‐GO were used to asses and compare their adsorption properties with cadmium(II). The anodic stripping voltammetry (ASV) peak, in the differential pulse voltammetry mode, for cadmium oxidation was found to be influenced by the presence of GO into the polymer, and also by their percentage of neutralization. The accumulation of cadmium(II) on the surface of the modified CPEs was performed under open‐circuit conditions taking an account the preconcentration time of the metal cation. The presence of GO enhances the electrical signal of the electrodes in short times of immersion in cadmium(II) solutions. This property contributed to get linear responses of the CPEs modified with the composites, which were influenced by their degrees of neutralization. The PAA‐GO 10N electrode with 10% of neutralization combined the influence of GO and the degree of neutralization in the same matrix, and also showed good performance in terms of its mechanical stability, it was chosen for preliminary studies on the selectivity of the electrode toward Zn(II) and Cu(II). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40846.     

Polynomial methods for the structured singular value with real parameters

We consider the structured singular value problem with real parametric uncertainty only. Using techniques from algebraic geometry, we propose two algorithms that in principle can yield the precise value of the structured singular value at a fixed frequency. Their ability to do so depends upon their ability to find all common roots to a system of polynomial equations. The first algorithm is applicable to problems with two real parameters each of multiplicity two. The second algorithm is applicable to problems with n distinct real parameters. These algorithms have proved useful in applications to aerospace control law analysis.