Application of the Galerkin-Vlasov method to the flexural analysis of simply supported rectangular Kirchhoff plates under uniform loads

Plates are important structural elements used to model bridge decks, retaining walls, floor slabs, spacecraft panels, aerospace structures, and ship hulls amongst. Plates have been modelled using three dimensional elasticity theory, Reissner’s theory, Kirchhoff theory, Shimpi’s theory, Von Karman’s theory, etc. The resulting plate equations have also been solved using classical and numerical techniques.In this research, the Galerkin-Vlasov variational method was used to present a general formulation of the Kirchhoff plate problem with simply supported edges and under distributed loads. The problem was then solved to obtain the displacements, and the bending moments in a Kirchhoff plate with simply supported edges and under uniform load. Maximum values of the displacement and the bending moments were found to occur at the plate center. The Galerkin Vlasov solutions for a rectangular simply supported Kirchhoff plate carrying uniform load was found to be exactly identical with the Navier double trigonometric series solution. http://dx.doi.org/10.4314/njt.v35i4.

Solution of free harmonic vibration equation of simply supported Kirchhoff plate by Galerkin-Vlasov method

This work studies the dynamic characteristics of simply supported rectangular thin plates undergoing natural transverse vibrations in harmonic motion. The governing partial differential equation for the free transverse vibration of the plate was solved by the Galerkin-Vlasov variational technique. The assumption of free harmonic motions reduced the governing equation to an algebraic eigen value eigenvector problem, which was solved in the space domain to obtain the eigen frequencies and modal shape functions of the vibrating Kirchhoff plate. The eigen frequencies and modal shape functions obtained were found to be identical with the results obtained by the classical methods of Navier and Levy for the same problem.Keywords: Kirchhoff plate, Galerkin-Vlasov method, harmonic vibration, natural vibrations, eigen frequencies

An Afro-Existential Approach to the Development of the Nigerian Society

The role of philosophy in nation building is hardly given the recognition it deserves in the African society. In this regard, philosophers are often seen as those who see problems where none exist, rather than people who inspire critical thinking. Yet, the role of philosophy in nation building cannot be dismissed with a wave of hand. The focus of this paper is basically to establish the relevance of existentialist philosophy to national development. To this end, we situate our discourse within a particular African context. The African world view would be discussed mainly from the context of the Igbo world view. This is the crux of the whole work. To this effect, the full implication of the Afro-existential approach will unfold as the work unfolds. One branch of philosophy that has made waves in various disciplines is existentialism. This paper is therefore an attempt to establish the relevance of existentialist philosophy to national development, with a particular focus on Nigeria. It understands existentialism as a trend in philosophy that lays emphasis on man's existence with regard to such themes as individual freedom and choice, and the individual creating meaning in a meaningless universe. In this connection, it examines the role of the Afro-existential discourse as a new approach in African philosophy. It addresses such questions as, why is Nigeria underdeveloped. Do we have to continue looking for historical forces or factors to blame? What can the philosopher and the existential discourse contribute to the development of Nigeria? It concludes that, confronted with the underdeveloped state of Nigeria, the existentialists do not overly ignore history. However, they are more concerned with the present situation and the choices that confront us as individuals. Making the right choices and taking the right steps today is therefore the way philosophers would establish their relevance through the existential discourse

The Impact of Intervention on Sexual Practices of HIV Positive Individuals in Southeast Nigeria

Objective. To describe the impact of repeating behavioral educational intervention on sexual practices of HIV positive individuals. Method. A prospective cohort study of HIV positive individual was conducted in southeast Nigeria from June 2007 to May 2008. Information on sexual practices was collected at initial visit; education was given and its impact was evaluated afterwards. Results. Knowledge about risk of unprotected intercourse increased by 41%, condom use by 27% (P < .001) and consistent condom use by 55% (P < .001). The significant predictors of consistent condom use include male gender, multiple sexual partner, as well as good knowledge of HIV transmission, higher educational status and being married. Non use of condom at postintervention survey were characterized by female gender (n = 4), monogamous relationship (n = 10), little or no education (n = 10), and unmarried (n = 7) respondents. Conclusion. Repeated behavioral education intervention improves consistent condom use among HIV positive individuals and will help curb the spread of HIV/AIDS

Burn-up calculation of the neutronic and safety parameters of thorium-uranium mixed oxide fuel cycle in a Westinghouse small modular reactor

Thorium fuel is presently a globally known future nuclear fuel alternative, having good neutronic, physical and chemical properties in addition to its spent nuclear fuel characteristic proliferation resistance. This research focused on the neutronic and safety parameters of thorium‐uranium mixed oxide fuel cycle, utilising three fissile enrichment zones, a departure from the conventional single enrichment. The aim was to determine the range of three fissile zones adequate for thorium‐uranium fuel cycle; investigating the performance efficiency of the fuel neutronic and inherent safety parameters in response to temperature differentials, which determines the viability of the fuel and core composition. Use was made of the MCNPX 2.7 code integrated with the CINDER90 fuel depletion code for steady‐state and burn‐up calculations. The keff, moderator temperature coefficient (MTC) and fuel temperature coefficient (FTC) of reactivity are affected by the range of fissile enrichment and fuel temperature which decreased with their respective increases. The MTC for all the moderator temperatures was within 0 to −40 pcm/K design value for UO2 fuel. Similarly, the FTC was within −3.5 to −1 pcm/K design value for all the fuel temperatures except after 2000 days, where a positive reactivity feedback was introduced. At ~86 MWd/kgHM single discharge burn‐up, the result shows that ~90% of the initial fissile load was utilised for energy production at the normal reactor operating temperature (600 K) with a slight reduction at higher fuel temperature. The total fissile inventory ratio (FIR), 233U/kg‐232Th and 239Pu/kg‐238U inventory ratios were significantly large and increased with burn‐up. It is remarkable that the FIR and the 233U/kg‐232Th inventory ratio did not reach conversion equilibrium until exit burn‐up. The large percentage fuel utilisation supports the advantage of fissile enrichment zoning in a thermal nuclear reactor core, making the chosen novel three fissile enrichment zones for thorium‐uranium fuel cycle reliable

Multidisciplinary approach to genomics research in Africa: the AfriCRAN model

This article is an outcome of the African Craniofacial Anomalies Research Network (AfriCRAN) Human Hereditary and Health (H3A) grant planning meeting in 2012 in Lagos, Nigeria. It describes the strengths of a multidisciplinary team approach to solving complex genetic traits in the craniofacial region. It also highlights the different components and argues for the composition of similar teams to fast track the discovery of disease genes, diagnostic tools, improved clinical treatment and ultimately prevention of diseases

Symphysiotomy in Zimbabwe; Postoperative Outcome, Width of the Symphysis Joint, and Knowledge, Attitudes and Practice among Doctors and Midwives

BACKGROUND: Obstructed labour remains one of the leading causes of maternal and foetal death and morbidity in poorly resourced areas of the world, where the 24 hours availability of a caesarean section (CS) cannot be guaranteed, and the CS related mortality rate is still high. In these settings, reinstatement of symphysiotomy has been advocated. The objectives were, in1994; to study perioperative and long-term complications of symphysiotomy and compare them to those related to CS for similar indications, in 1996; to measure the symphyseal width after symphysiotomy and compare it to that after normal vaginal delivery, and, in 1998; to assess knowledge, attitudes and practice related to symphysiotomy among doctors and midwives in Zimbabwe. METHODS AND FINDINGS: Thirty-four women who had undergone symphysiotomy and 29 women who had undergone a CS for obstructed labour were interviewed. The symphyseal widths of 19 women with a previous symphysiotomy were compared to that of 92 women with previous normal vaginal deliveries, using ultrasound technique. Forty-one doctors and 39 midwives, in three central hospitals and seven district hospitals in Zimbabwe, were interviewed about symphysiotomy. None of the 34 women reported serious soft tissue injuries or infections post symphysiotomy. Long-term complications after symphysiotomy do not differ notably from those after CS for similar indications. The intra-articular width of the symphysis pubis is increased after a symphysiotomy. Seventy-nine of the 80 interviewed health care workers knew about symphysiotomy. One obstetrician had performed symphysiotomies. Two-thirds of the participants considered symphysiotomy an obsolete and second-class operation, but lifesaving and appropriate in remote areas of Zimbabwe. Ten of 13 midwives in remote areas wanted to carry out symphysiotomies themselves. CONCLUSIONS: No severe complications due to symphysiotomy were revealed in this study. The results suggest that a modest permanent enlargement of the pelvis post symphysiotomy (together with the absence of a scarred uterus) may facilitate subsequent vaginal delivery. Doctors and midwives working in district hospitals have a more positive attitude to symphysiotomies than the colleagues in central hospitals. Obstetricians (who would have to do the teaching), working in the large urban hospitals almost exclude symphysiotomy as an alternative management in Zimbabwe

Strengthening the emergency healthcare system for mothers and children in The Gambia

A system to improve the management of emergencies during pregnancy, childbirth, infancy and childhood in a region of The Gambia (Brikama) with a population of approximately 250,000 has been developed