Responding to Negative Public Attitudes towards Immigration through Analysis and Policy: regional and unemployment dimensions

This paper examines two key dimensions of the impact of immigration for Australia and related policy aspects. One is sub-national and the other is national. They are, first, the regional location aspects of immigration and, second, the aggregate unemployment implications of immigration. These are chosen so as to focus on two important issues that condition public attitudes towards immigration. In relation to the first, there is a common positive view that channelling migration towards regional areas assists regional development and reduces pressure on metropolitan areas. The paper reviews regional concepts embodied in Australian immigration policy and the ways in which visa arrangements have implemented policies geared towards the regional dispersal of immigrants. Using official data, it discusses the demographic impacts of these policies and, in particular, considers the extent to which immigrants to regional Australia remain there over the longer term. In relation to unemployment, a common concern is that immigrants take jobs from local workers. The paper examines—using statistical regression methodology—the relationship between immigration and national aggregate unemployment in Australia. It evaluates the net consequences of immigration for both existing residents and new arrivals together. The paper concludes that, with good policy design in each case, regional location encouragement can be effective for immigrants and that immigrants need not take more jobs than they create. The analysis demonstrates that mixed-methods approaches to important social science issues can be productive, and helpful also for policy. Evidence, such as that presented in this paper, offers a powerful basis from which to counter negative public and political discourses surrounding immigration in contemporary Australia.This work was partly supported by the Australian Council of Learned Academies from the Australian Research Council Grant [LS120100001 “Securing Australia’s Future: Project 1 – Australia’s Comparative Advantage”]

R&D, Innovation and Productivity: The Role of Public Support

Research and innovation are widely agreed to be major driving forces behind long-term productivity and economic growth. However, the relationships have proven to be difficult to quantify. We make reference to the international literature and draw on recenI. Productivity Performance: The Australian Experience 　II. Innovation and Productivity 　III. Knowledge and Other Intangibles 　IV. Public Funding 　V. Public R&D Capital and Productivity Growth 　VI. Conclusions 　REFERENCE

From binder to mixture: experimental programme on permanent deformation behaviour

Asphalt mixture, the most common road construction material, comprises bitumen, filler, fine and coarse aggregates, and air voids. Traditionally and for simplification, the mixture is treated as a continuous and homogenous material confined in the domain of linear behaviour. The demand for more durable roads, particularly with the progressive growth in traffic volumes and loads, has raised the requirement for improved design methods. Wisely, before the complex adoption of the nonlinear behaviour, understanding the nature of the internal stress-strain relationships at different scales and determining their linearity limits is essentially required taking into consideration the time and temperature dependency. So far, most experimental programs have been concerned with testing either asphalt mixture or bitumen in isolation. This thesis is intended to establish a systematic experimental investigation from binder to the asphalt mixture scale in terms of permanent deformation behaviour. Preliminary conclusions of the components contributions, their interactions, and the effect on the total macroscopic response are drawn from the experimental observations. Investigation of the fillers influence on the viscoelastic property of the mastic (filler +bitumen) binder in the dynamic shear rheometer (DSR), results exhibited that binder behave nonlinearly at high shear stress levels and the linearity range reduces with increasing filler content and/or raising the temperature. Although filler inclusion increased the deformation resistance (stiffness) of the binder, its recoverability decreased. Consequently, a new binder rutting evaluation test was designed to distinguish between the two rutting resistance mechanisms; stiffness and recovery. Results from the new test indicated that the linearity of the modified binders begins after an initial inherent nonlinearity stage and before a secondary nonlinearity stage triggered by the applied state of stresses in the DSR. A new designed mortar type was developed from the mastic and originated from a standard asphalt mixture. The focus of this part in the research emphasised on measuring the stiffening effect of fine aggregates utilising a constitutive stress-strain relationship and determining the influence on the viscoelastic behaviour. Results indicated that the stiffening effect varies depending on the stress condition (uniaxial, triaxial, or shear), temperature, fine aggregate gradation, and binder with filler content. The stress linearity limit was also found to vary at different degrees with the previous parameters. Uniaxial compression constant stress and strain rate tests were conducted on asphalt mixtures of different aggregate gradations at 30 and 500C. X-ray CT was incorporated to characterise the coarse aggregates and air voids through advanced image analysis techniques. The test was shown to be insensitive to the asphalt mixture type in terms of air voids uniformity. Mixtures of coarse aggregates produced larger size and smaller number of air voids, opposite to the fine aggregate ones. Comparing the stiffening effect between fine and coarse aggregates, it was revealed that the air void content is a key factor. Finally, the radial strain as measured along the height followed the pattern of air void distribution in the specimen and exhibited both tensile and compressive forms

Antibacterial effects of natural adsorbent prepared from two local Sudanese agricultural waste mango seeds and date's stones and their uses in removal of contamination from fluid nutrient

Background: The use of biologically activated carbon (BAC) in drinking water purification is reviewed. Aim: The study was aimed to determine the efficiency of natural adsorbent with antibacterial effects against the strains of E. coli, Shigella spp. and Faecalis bacteria which are found in stimulated water samples. Methods: This was an analytical laboratory based study. The study was carried out at laboratory of Ahfad University for Women at Omdurman in Khartoum state. Two samples of mango seeds and date’s stone were used to carry out these experiments. Mango and date were brought from the local market (Sug El Arabi ). The general process to produce activated carbon is based on carbonizing and activating the carbon aqueous precursor material.  The powder was put in crucible and 1 gram of zinc chloride was added to it. It was incinerated at 350 0C for not less than 3 hours in an oven. It was cooled in a room temperature. Results Activated carbon prepared from mango seeds and date’s stone was found to be very active as antibacterial against E.coli, Shigella and E.faecalis bacteria. The result showed zone of inhibition for each bacteria. The greater zone of inhibition was against E.faecalisdone by both samples. The more effective sample in the three strains was AC from mango seeds. Conclusions: These antibacterial results are good indicators to use natural adsorbent in food processing, sugar purification and food industry

From binder to mixture: experimental programme on permanent deformation behaviour

Asphalt mixture, the most common road construction material, comprises bitumen, filler, fine and coarse aggregates, and air voids. Traditionally and for simplification, the mixture is treated as a continuous and homogenous material confined in the domain of linear behaviour. The demand for more durable roads, particularly with the progressive growth in traffic volumes and loads, has raised the requirement for improved design methods. Wisely, before the complex adoption of the nonlinear behaviour, understanding the nature of the internal stress-strain relationships at different scales and determining their linearity limits is essentially required taking into consideration the time and temperature dependency. So far, most experimental programs have been concerned with testing either asphalt mixture or bitumen in isolation. This thesis is intended to establish a systematic experimental investigation from binder to the asphalt mixture scale in terms of permanent deformation behaviour. Preliminary conclusions of the components contributions, their interactions, and the effect on the total macroscopic response are drawn from the experimental observations. Investigation of the fillers influence on the viscoelastic property of the mastic (filler +bitumen) binder in the dynamic shear rheometer (DSR), results exhibited that binder behave nonlinearly at high shear stress levels and the linearity range reduces with increasing filler content and/or raising the temperature. Although filler inclusion increased the deformation resistance (stiffness) of the binder, its recoverability decreased. Consequently, a new binder rutting evaluation test was designed to distinguish between the two rutting resistance mechanisms; stiffness and recovery. Results from the new test indicated that the linearity of the modified binders begins after an initial inherent nonlinearity stage and before a secondary nonlinearity stage triggered by the applied state of stresses in the DSR. A new designed mortar type was developed from the mastic and originated from a standard asphalt mixture. The focus of this part in the research emphasised on measuring the stiffening effect of fine aggregates utilising a constitutive stress-strain relationship and determining the influence on the viscoelastic behaviour. Results indicated that the stiffening effect varies depending on the stress condition (uniaxial, triaxial, or shear), temperature, fine aggregate gradation, and binder with filler content. The stress linearity limit was also found to vary at different degrees with the previous parameters. Uniaxial compression constant stress and strain rate tests were conducted on asphalt mixtures of different aggregate gradations at 30 and 500C. X-ray CT was incorporated to characterise the coarse aggregates and air voids through advanced image analysis techniques. The test was shown to be insensitive to the asphalt mixture type in terms of air voids uniformity. Mixtures of coarse aggregates produced larger size and smaller number of air voids, opposite to the fine aggregate ones. Comparing the stiffening effect between fine and coarse aggregates, it was revealed that the air void content is a key factor. Finally, the radial strain as measured along the height followed the pattern of air void distribution in the specimen and exhibited both tensile and compressive forms

Microbiological Assessment of Drinking Water Quality in Omdurman City

A study was conducted to evaluate the drinking water of Omdurman city, by looking into the microbiological aspect. Ten samples were taken randomly from different parts of Omdurman city during three seasons (winter, summer and autumn) for two successive years. Results indicated that most of the samples were contaminated by bacteria, including Coliform, Escherichia coli and Fecal streptococcus. The contamination percentage was higher in the rainy season and summer, while in winter was the least

Developing the multiple stress–strain creep recovery (MS-SCR) test

While most published work from Europe has been concerned with evaluating binders’ resistance to rutting based on their stiffness (deformation resistance), work originating in the US has mainly been concerned with ranking binders based on their recoverability in a multiple stress form. This paper details the design of a new modified multiple stress–strain creep recovery (MS-SCR) test. The test is designed to evaluate binders’ rutting resistance based on two rutting resistance mechanisms: stiffness and recoverability. A preliminary investigation is presented in this paper followed by details of the design of the new modified test. A 40/60 penetration grade bitumen and bitumen-filler mastics prepared with three filler concentrations (35%, 50%, and 65% filler content by mass of mastic) were tested. In addition, two polymer modified bitumens (PMBs) using the same base bitumen type were examined for validation. Two parameters are introduced to characterise the short and long recovery in the new test. In terms of stiffness, the test allows the behaviour of binders at different stress levels and loading cycles to be studied and produces a new parameter that can quantify the degree of modification. Finally, a relationship between nonlinearity and normal force in the test was investigated

The Effect of Seed Size and Burial Depth on the Germination, Growth and Yield of Sunflower (Helianthus annus L.)

A pot experiment was conducted in the year 2016 to evaluate the effect of seed size and burial depth of sunflower on the germination, growth and some yield components. The experiment was laid in a split plot design with seed size as main plot and burial depth as sub-plot with three replicates. The results indicated that seed size had significant effect on germination, plant height, number of leaves, leaf area, number of seeds per plant. The analysis indicated that there was no significant effect for seed size on head diameter, head weight and seed weight. A significant difference was observed between the burial depth, and the interaction between seed size and burial depth showed significant effect

Dynamic compression of foam supported plates impacted by high velocity soil

The response of back-supported buffer plates comprising a solid face sheet and foam core backing impacted by a column of high velocity particles (sand slug) is investigated via a lumped parameter model and coupled discrete/continuum simulations. The buffer plate is either resting (unattached) or attached to a rigid stationary foundation. The lumped parameter model is used to construct maps of the regimes of behaviour with axes of the ratio of the height of the sand slug to core thickness and the normalised core strength. Four regimes of behaviour are identified based on whether the core compression ends prior to the densification of the sand slug or vice versa. Coupled discrete/continuum simulations are also reported and compared with the lumped parameter model. While the model predicted regimes of behaviour are in excellent agreement with numerical simulations, the lumped parameter model is unable to predict the momentum transmitted to the supports as it neglects the role of elasticity in both the buffer plate and the sand slug. The numerical calculations show that the momentum transfer is minimised for intermediate values of the core strength when the so-called “soft-catch” mechanism is at play. In this regime the bounce-back of the sand slug is minimised which reduces the momentum transfer. For high values of the core strength, the response of the buffer plate resembles a rigid plate with nearly no impulse mitigation while at low values of core strength, a slap event occurs when the face sheet impinges against the foundation due to full densification of the foam core. This slap event results in a significant enhancement of the momentum transfer to the foundation. The results demonstrate that appropriately designed buffer plates have potential as impulse mitigators in landmine loading situations

Energy absorption in lattice structures in dynamics: Experiments

Lattice structures offer the potential to relatively easily engineer specific (meso-scale properties (cell level)), to produce desirable macro-scale material properties for a wide variety of engineering applications including wave filters, blast and impact protection systems, thermal insulation, structural aircraft and vehicle components, and body implants. The work presented here focuses on characterising the quasi-static and, in particular, the dynamic load-deformation behaviour of lattice samples. First, cubic, diamond and re-entrant cube lattice structures were tested under quasi-static conditions to investigate failure process and stress–strain response of such materials. Following the quasi-static tests, Hopkinson pressure bar (HPB) tests were carried out to evaluate the impact response of these materials under high deformation rates. The HPB tests show that the lattice structures are able to spread impact loading in time and to reduce the peak impact stress. A significant rate dependency of load-deformation characteristics was identified. This is believed to be the first published results of experimental load-deformation studies of additively manufactured lattice structures. The cubic and diamond lattices are, by a small margin, the most effective of those lattices investigated to achieve this