Life cycle assessment and economic analysis of Reusable formwork materials considering the circular economy

Economic development and population growth have impacted on fossil-based energy consumption, contributing to environmental pollution. Adopting circular economy research is more pressing than ever to ease pressure on the environment and the economy. Evaluating the best construction materials is not new. To date, many researchers have assessed materials using various criteria. Formwork differs from other construction materials in terms of serviceability and reusability. These materials may be reused multiple times (from 7 to around 50 times). This raises the question of which material is the best from a sustainability perspective. In this paper we have evaluated four of the most widely-used formwork materials used in the construction of buildings in Malaysia. These include plastic, steel, plywood and timber. Evaluations of life cycle assessment (LCA), embodied energy, and life cycle cost (LCC) were conducted from cradle to cradle. For a single use of formwork, timber is best in all categories except human non-carcinogenic toxicity. However, when 50 reuses are considered for the same wall a completely different result arises. In the environmental category, steel formwork produces the lowest emissions and impact in all categories except global warming potential (GWP). Plastic formwork has the lowest carbon emissions. In terms of embodied energy and cost, plastic formwork presents the best option being approximately 20% lower than steel formwork. Because of the inconsistency in the results for LCA, embodied energy, and LCC for 50-cycles of usage, a multi-criteria decision-making (MCDM) tool was used to normalize the results. The MCDM shows that plastic formwork is an ideal choice for sustainability among the alternatives considered

Corruption and Economic Growth in Nigeria (1980-2013)

Corruption is as aged as the existence of man and it exists in all sphere of human life. The  persistency  of  corruption  erodes  the  social  economic  value  of  a  nation. The study investigates the relationship between corruption and economic growth in Nigeria, in the period 1980-2013, using the VAR analysis. The study finds the existence of long-term relationship between corruption and unemployment growth on the economic growth of Nigeria. Also, the study found no short-term relationship in corruption and unemployment on economic growth. Hence, the result in the analysis shows that corruption positively has a strong influence on the output of Nigeria. So the rise in growth rate experienced in Nigeria is influenced by high corruption rate in the country, which is making the few rich to be richer, eradicating the middle class and making the poor to be poorer. Therefore, there is a need to develop political will to prosecute anyone found guilty of corruption irrespective of their position, tribe, religion or party affiliation. Such a punishment would also serve as a deterrent to others and help improve real economic growth and development

Analysis of Foreign and Domestic Investment on Economic Growth in Nigeria (1980-2013)

Several factors have hampered economic growth in Nigeria, though there has been improvement in the recent times. Nevertheless, it remains fragile and is not strong enough to significantly reduce the prevailing level of poverty in the country. Against this backdrop, the study investigates the relationship between foreign and domestic investment on Economic growth in Nigeria, during the period 1980-2013, using Vector Error Correction Model (VECM). The study finds out that foreign and domestic investment have a strong influence both in short and long run, on the economic growth of Nigeria. The result shows unidirectional long-run causality between domestic investments to real GDP in Nigeria. Also, there is unidirectional long-run causality between exchange rate and real GDP in Nigeria. The result implies that change in current GDP is better explained by domestic investment and exchange rate rather than national income, foreign direct investment and credit to private sector. Hence, the government may encourage foreign investors to invest in the high risk areas, where the domestic investment lacks the technology and experiences needed

Corrosion study of pipeline material for seabed sediment in tropical climate

Corrosive environments such as marine sediments can cause corrosion to steel pipelines at any time when certain conditions are met. Seabed sediment could cause severe corrosion damage due to its corrosiveness to the pipelines buried under it. Many consequences could take place in case if there is incident in oil/gas pipelines. Successfully identifying elements of corrosion in marine sediment would enhance the future of steel structure protection and monitoring systems. This article focuses on the behaviour of corrosion rate of steel located near shore environment and the aim is to determine the effect of sediment on corrosion of steel. To investigate that, simulated near shore sediment conditions have been used where the steel coupons buried in sediments which have different characteristics. Weight loss technique has been implemented to determine the weight loss rate of the steel specimens. Based on the results of this study, metal weight loss increases as the duration of exposure to seabed sediment environment become longer. The sea sediment simulated condition has given significant levels of corrosion. Conclusively, the corrosion rate of steel in seabed sediment located in tropical region is complicated and further studies are suggested

Probing scalar-pseudoscalar mixing in the CP violating MSSM at high-energy e+e−e^+e^- colliders

We study the production processes $e^+e^-\to H^0_iZ$, $H^0_iH^0_j$ and $H^0_i\nu_e\overline \nu_e$ in the context of the CP violating MSSM. In a given channel we show that the cross-section for all i (=1,2,3) can be above 0.1 fb provided M_{H_{2,3}}\la 300 GeV. This should be detectable at a Next Linear Collider and would provide evidence for scalar-pseudoscalar mixing.Comment: 17 pages, RevTex, 4 ps figures, figure 4 changed, minor modifications to text, version to appear in PR

Unitarity analysis of general Born-Infeld gravity theories

We develop techniques of analyzing the unitarity of general Born-Infeld (BI) gravity actions in D-dimensional spacetimes. Determinantal form of the action allows us to find a compact expression quadratic in the metric fluctuations around constant curvature backgrounds. This is highly nontrivial since for the BI actions, in principle, infinitely many terms in the curvature expansion should contribute to the quadratic action in the metric fluctuations around constant curvature backgrounds, which would render the unitarity analysis intractable. Moreover in even dimensions, unitarity of the theory depends only on finite number of terms built from the powers of the curvature tensor. We apply our techniques to some four-dimensional examples.Comment: 26 pages, typos corrected, version to appear in Phys. Rev.

One-loop contributions of charginos and neutralinos to W-pair production in E+ E- collisions

We study the one-loop effects of charginos and neutralinos on the helicity amplitudes for \eeww in the minimal supersymmetric standard model. The calculation is tested by using two methods. First, the sum rule for the form factors between \eeww and the process where the external $W^\pm$ bosons are replaced by the corresponding Goldstone bosons $\omega^\pm$ is employed to test the analytic expression and the accuracy of the numerical program. Second, the decoupling property in the large mass limit is used to test the overall normalization of the amplitudes. These two tests are most effectively carried out when the amplitudes are expanded in terms of the modified minimal subtraction ($\bar{\rm MS}$) couplings of the standard model. The resulting perturbation expansion is valid at collider energies below and around the threshold of the light supersymmetric particles. We find that the corrections to the cross section of the longitudinally polarized $W$-pair production can be as large as -1.4% at the threshold of the light chargino-pair production for large scattering angles. We also study the effects of the CP-violating phase in the chargino and neutralino sectors on the helicity amplitudes. We find that the resulting CP-violating asymmetries can be at most 0.1%.Comment: 30 pages, 25 figures, Final verision, To appear in Physical Review D, Several sentences are improve