Optimum design of reinforced concrete rectangular columns subjected to axial compression and biaxial bending moments

This study investigates the optimum design in terms of minimum cost of reinforced concrete rectangular columns subjected to axial compression force and biaxial bending moments about x and y axes. For the optimisation process, the Generalised Reduced Gradient (GRG) technique was implemented which is embedded within Excel Solver add-in tool. GRG method was adopted because of its robustness and efficiency in dealing with a wide range of engineering problems as demonstrated by several works available in the literature. GRG is regarded as one of the best deterministic local optimisation methods. Equally important, the GRG is part and parcel of Microsoft Excel which means that there is no need to pay for extra licence to run any optimisation problem. The formulated models for the design of reinforced concrete columns and the imposed constraints were based on the provisions of Eurocode 2 (EC2). The design variables were the cross sectional dimensions (width and depth) and reinforcing steel area. It is worthwhile to mention that the position and orientation of neutral axis were also considered as design variables in order to avoid solving the highly nonlinear simultaneous equations which is time consuming and not necessarily leading to a convergent solution. Several design parameters, such as materials cost ratios and depth to width ratios were tested. Consequently, optimum design charts were developed for a wide range of practical combination of axial compression forces and eccentricities in both x and y directions. Following a comprehensive investigation of the minimum cost problems carried out for different cases, one can conclude that variation of depth to width ratio may have noticeable effect on the optimum width, depth and area of steel only when the eccentricity in y direction (ey) is much greater than the eccentricity in x direction (ex). Furthermore, the effect of steel to concrete unit cost ratio (Cs/Cc) is more obvious at larger loads and higher eccentricities

An integrated model to evaluate water-energy-food nexus at a household scale

ArticleThis is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.To achieve a sustainable supply and effectively manage water, energy and food (WEF) demand, interactions between WEF need to be understood. This study developed an integrated model, capturing the interactions between WEF at end-use level at a household scale. The model is based on a survey of 419 households conducted to investigate WEF over winter and summer for the city of Duhok, Iraq. A bottom-up approach was used to develop this system dynamics-based model. The model estimates WEF demand and the generated organic waste and wastewater quantities. It also investigates the impact of change in user behaviour, diet, income, family size and climate. The simulation results show a good agreement with the historical data. Using the model, the impact of Global Scenario Group (GSG) scenarios was investigated. The results suggest that the ‘fortress world’ scenario (an authoritarian response to the threat of breakdown) had the highest impact on WEF.This work was financially supported by the Human Capacity Development Program in Higher Education (HCED) in Kurdistan, Iraq. We acknowledge the support for this work provided by Dr. Sarah Ward and Ziyad Ahmed

Validation of the Chinese version of the Sense of Self (SOS) Scale

published_or_final_versionSpringer Open Choice, 28 May 201

Validation of a survey tool for use in cross-cultural studies

There is a need for tools to measure the information patients need in order for healthcare professionals in general, and particularly pharmacists, to communicate effectively and play an active part in the way patients manage their medicines. Previous research has developed and validated constructs to measure patients’ desires for information and their perceptions of how useful their medicines are. It is important to develop these tools for use in different settings and countries so that best practice is shared and is based on the best available evidence. Objectives: this project sought to validate of a survey tool measuring the “Extent of Information Desired” (EID), the “Perceived Utility of Medicines” (PUM), and the “Anxiety about Illness” (AI) that had been previously translated for use with Portuguese patients. Methods: The scales were validated in a patient sample of 596: construct validity was explored in Factor analysis (PCA) and internal consistency analysed using Cronbach’s alpha. Criterion validity was explored correlating scores to the AI scale and patients’ perceived health status. Discriminatory power was assessed using ANOVA. Temporal stability was explored in a sub-sample of patients who responded at two time points, using a T-test to compare their mean scores. Results: Construct validity results indicated the need to remove 1 item from the Perceived Harm of Medicines (PHM) and Perceived Benefit of Medicines (PBM) for use in a Portuguese sample and the abandon of the tolerance scale. The internal consistency was high for the EID, PBM and AI scales (alpha>0.600) and acceptable for the PHM scale (alpha=0.536). All scales, except the EID, were consistent over time (p>0.05; p<0.01). All the scales tested showed good discriminatory power. The comparison of the AI scale with the SF-36 indicated good criterion validity (p<0.05). Conclusion: The translated tool was valid and reliable in Portuguese patients- excluding the Tolerance scale. Some of the scales may benefit from further refinement, such as the PHM subscale

The Necessary and Sufficient Conditions of Separability for Multipartite Pure States

In this paper we present the necessary and sufficient conditions of separability for multipartite pure states. These conditions are very simple, and they don't require Schmidt decomposition or tracing out operations. We also give a necessary condition for a local unitary equivalence class for a bipartite system in terms of the determinant of the matrix of amplitudes and explore a variance as a measure of entanglement for multipartite pure states.Comment: Submitted to PRL in Sep. 2004, the paper No is LV9637. Submitted to SIAM on computing, in Jan., 2005, the paper No. is SICOMP 44687. Under reviewing no

Palynomorphs and floral bloom as taxonomic characters in some species of the genus Amaranthus l. (Aamaranthaceae)

Fresh flowers of five species of Amaranthus were studied and documented in detail using light microscope to examine their morphology and pollen characteristics in relation to taxonomy. These species include Amaranthus spinosus, A. viridis, A. hybridus, A. australis and A. tricolor. The species showed close relationship in their pollen surface characteristics with some slight variations in psilate, micropitted or microrugulate ornamentations. The microscopic study of the pollens revealed the presence of 5 types of pollen apertures which include dicolpate, monolete, Inaperaturate, periporate and triporate. The analysis of mean polar and equatorial measurement i.e. the pollen sizes showed that the largest pollen was recorded in A. hybridus (61.95±2.40μm) and the smallest pollen was recorded in A. spinosus (23.70±0.65μm). The mean density of pollens was found to be highest in A. australis (12.55±1.13mm2) and the lowest mean density was recorded in A. hybridus (1.29±0.05mm2). Two diagnostic shapes were noticed in the samples studied, these are – spherical grains in A. spinosus and A. viridis and oval grains in A. hybridus, A. australis and A. tricolor. The study revealed that floral and palynological characters are of taxonomic significance in the genus.Keywords: Pollen morphology, flower, taxonomy, Amaranthus

On SUSY curves

In this note we give a summary of some elementary results in the theory of super Riemann surfaces (SUSY curves)

Quantification of respiratory parameters in patients with temporal lobe epilepsy

Dysfunction affecting cardiac or pulmonary systems has been postulated as a major factor in sudden death in epilepsy (SUDEP). Whilst the majority of studies of cardiorespiratory function have focused on changes during seizures, here we investigate whether epilepsy influences basal respiratory parameters in patients with temporal lobe epilepsy (TLE) during the interictal period. Spirometry was performed in 10 females and 10 males. Measurements of Vital Capacity (VC), Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1) and ratios of FEV1 to FVC (FEV1/FVC) were obtained, and these values were analyzed as percentages of predicted values. None of the patients had chronic obstructive pulmonary disease and no significant alterations in respiratory function tests were found among these patients. No association between seizure frequency, antiepileptic drugs and SUDEP could be found in this study. Although the study did not identify any specific respiratory abnormality in TLE patients during the interictal period, re-evaluation of clinical data on pulmonary disorders in people with epilepsy should be better investigated

Carbon flow pattern in the forest zones of Nigeria as influenced by land use change

Forest in Nigeria plays a much wider role in the overall balance of issues affecting the country than those of climate change alone. Nigeria&rsquo;s tropical forest is depleting fast, due largely to uncontrolled human activities. Poverty, urbanization, population growth and insecurity are the major causes of this trend. Tracking carbon flow in these forest life zones will help account for the effect of these activities on the environment. COPATH, an acronym for Total Carbon Flow from Conversion to Agriculture, Pasture, Harvest and OTHER land-uses including construction of dams, roads, forest fires and human settlement, etc., was used for tracking carbon flow in the forest zones. From the five forest life zones, total carbon stored was estimated to be 2.55 TgC. The four activities of agriculture, harvest, pasture and bush burning were pronounced in contributions to land use changes, particularly to forest depletion. In this paper it is shown that carbon emission was highest from harvesting activity in year 2000, principally from clear-cutting activity in the lowland rainforest as against that of 1990 study, which showed agricultural activity as the major anthropogenic activity leading to carbon release into the atmosphere. Further, it is shown that the value of carbon emission is on the increase as compared to the earlier study with 1990 as the base year. During the two periods of study, it was however, observed that the relative contribution of each of the activities that are responsible for deforestation and affects carbon flow pattern in the forest zones and invariably causes carbon emission had not changed. Though a look at the fractional contribution of each of these activities in 2000 as against that of 1990 estimates shows a marked change. The study also concludes that if there is no change in the estimated deforestation rate of 2.23% per annum of the forest formations, lowland rainforest and riparian forests are likely to disappear by 2040.Key words: Carbon flow pattern, forest life zone, land use, human activities, deforestation