108 research outputs found
Effect of Jet Reynold’s Number on Nusselt Number for Convective Impingement Air Cooling on a Hot Plate
Studies were carried out to determine the Convective Heat Transfer Coefficient, h, under multiple jets of impinging cold air on a target heated flat plate. Tests were run with air- distribution plates with hole diameters, d, of 1.5mm, 2.0mm, 2.5mm and 3.0mm. The target plate is a carbon-steel flat plate of 6mm thickness, instrumented with a total of three Chromel-Alumel K-type thermocouples. The plate is electrically heated using a variable supply current input. Test were run at various cooling air flow rate G, between 1.0kg/m3, sec to 3.0kg/m3, sec. Distribution plate-to-target plate distance Z(mm), was varied between 100mm to 200mm. Heat input to the target plate Q Watt, was varied to give a heat flux rate between 10 to 100 watts. Results obtained were reduced and analyzed by evaluating for the dependence of h on the impingement jet diameter,Jet Reynolds Number, and the coolant mass flow rate G. Correlations were done, using the dimensionless parameters of Nusselt Number, Reynolds Number and Prandtl Number. Based on the results obtained, it is proposed that within the Reynolds Number range of 1500 to 2000, correlation may be made with:-  = 0.15Re0.58Pr0.33 Keywords: Reynold’s Number, Nusselt Number, Prandtl Number, Impingement, Cooling, Heat transfer Coefficien
DEPRESSION AND STRESS AS CORRELATES OF SUICIDE THOUGHT AMONG UNDERGRADUATES OF IMO STATE UNIVERSITY, OWERRI.
This study investigated Depression, self-esteem and stress as correlates of suicide thoughts among university students of Imo State University, Owerri. Using a descriptive survey design, the study adopted a purposive sampling technique to select 402 undergraduates (208 males and 194 females) from all the 12 faculties of Imo state University, Owerri. Beck Depression Inventory, Becks’ Suicide Ideation Inventory and the Rosenberg self-esteem scale were used as instruments for data collection. Data analysis was done using Pearson Product Moment Correlation (PPMC) at a .05 level of significance. The study revealed a significant correlation between the independent variables (Depression, self-esteem and stress) and the dependent variable (Suicide thought) in the following order, Depression R=(400) = 0.216, p<.05, Self-esteem R=(400) = 0.314, p<.05 and Stress R=(400) = 0.174, p<.05). Among the recommendation is the fact that Lots of awareness and knowledge about suicidal thoughts among undergraduates should be created to provide a guideline for possible prevention program or treatments for those students who are experiencing the ideas of suicidal. This study came to existence to raise awareness about suicidal ideations' risk factors and prevention so that university students in crisis may be recognized and helped
DEPRESSION AND STRESS AS CORRELATES OF SUICIDE THOUGHT AMONG UNDERGRADUATES OF IMO STATE UNIVERSITY, OWERRI.
This study investigated Depression, self-esteem and stress as correlates of suicide thoughts among university students of Imo State University, Owerri. Using a descriptive survey design, the study adopted a purposive sampling technique to select 402 undergraduates (208 males and 194 females) from all the 12 faculties of Imo state University, Owerri. Beck Depression Inventory, Becks’ Suicide Ideation Inventory and the Rosenberg self-esteem scale were used as instruments for data collection. Data analysis was done using Pearson Product Moment Correlation (PPMC) at a .05 level of significance. The study revealed a significant correlation between the independent variables (Depression, self-esteem and stress) and the dependent variable (Suicide thought) in the following order, Depression R=(400) = 0.216, p<.05, Self-esteem R=(400) = 0.314, p<.05 and Stress R=(400) = 0.174, p<.05). Among the recommendation is the fact that Lots of awareness and knowledge about suicidal thoughts among undergraduates should be created to provide a guideline for possible prevention program or treatments for those students who are experiencing the ideas of suicidal. This study came to existence to raise awareness about suicidal ideations' risk factors and prevention so that university students in crisis may be recognized and helped
Simulation of A Mathematical Model Of Hepatitis B Virus Transmission Dynamics In The Presence Of Vaccination And Treatment
In this paper, a mathematical model for the transmission dynamics of hepatitis B virus (HBV) infection incorporating vaccination and treatment as control parameters is presented. The basic reproduction number, , as a threshold parameter, was constructed, in terms of the given model parameters, by the next generation method.   was numerically assessed for its sensitivity to vaccination and treatment parameters. A unique disease-free equilibrium state was determined, indicating possibility of control of HBV disease. The model was solved numerically using Runge-Kutta method of order four to evaluate the effects of vaccination and treatment parameters on the prevalence of the disease. The numerical results of the sensitivity analysis show that increasing either vaccination or treatment rate has the potential of reducing  below unity. The results of the numerical simulations of the model show that effective vaccination, treatment or a combination of both of them as a control strategy can eradicate HBV disease, with the combination being far better than either of them. Finally, these findings strongly suggest that high coverage of vaccination and treatment are crucial to the success of HBV disease control
Modelling Hepatitis B Virus Transmission Dynamics In The Presence of Vaccination and Treatment
Hepatitis B is a global threat as over a billion people have been infected and about 300 million people die annually across the world. In this paper, a mathematical model for the transmission dynamics of hepatitis B virus infection considering vaccination and treatment as control parameters in the host population is presented. First, the disease-free equilibrium state of the model was determined. The next generation method was used to determine the basic reproduction number,  as a threshold parameter, in terms of the given model parameters.  was analytically evaluated for its sensitivity to vaccination and treatment parameters. It was proved that the disease-free equilibrium state is locally asymptotically stable if the  is below unity, otherwise, it is unstable. Local stability of the endemic equilibrium state was established using the centre manifold theory. The analytical results of the  show that increasing the proportion of people who receive vaccines, either at birth or later in life, reduces it below unity. Similarly, increasing the proportion of carriers who receive treatment achieves the same purpose. The result of the local stability analysis of the disease-free equilibrium state shows that the disease can be eliminated if  is below unity. The result of the centre manifold theory on the endemic equilibrium state shows that the disease can persist as the value of  increases above one. The findings of this study strongly suggest a combination of effective vaccination and treatment as a control strategy is crucial to the success of HBV disease control
Effect of intrathecal midazolam on single dose morphine-bupivacaine co-mixture for spinal analgesia in labour
Background: When spinal analgesia is used for relief of labour pain, a major challenge has been how to extend its duration without increasing the associated adverse effects. The aim of this study was to evaluate the effect of intra-thecal midazolam on pain relief by low dose bupivacaine and morphine mixture administered intrathecally to women in labour.Methods: 160 labouring women, aged between 18 and 40 years gave consent and enrolled for this comparative study. The women were randomly allocated into two equal groups, MBM and BM. Group MBM received intrathecal 2.0 mg midazolam, 2.5 mg bupivacaine and 150 mcg morphine. Group BM received intra-thecal 2.5 mg bupivacaine and 150 mcg morphine. An epidural bolus dose of bupivacaine 10 mg plus fentanyl 25 mcg was given whenever rescue analgesia was needed. Foeto-maternal parameters, were assessed and recorded.Results: Duration of effective spinal analgesia was significantly longer in group MBM than in group BM, p=0.0001. More participants in group BM had epidural rescue analgesia compared to group MBM, p=0.001. More participants in group MBM had adequate spinal analgesia till delivery compared to group BM, p=0.001. All the participants in both groups were able to ambulate without support after 30 minutes following the injection of spinal drugs. Nausea and vomiting occurred less commonly in group MBM than in BM, p=0.006.Conclusions: Addition of midazolam to bupivacaine-morphine co-mixture significantly prolonged the duration of spinal analgesia without affecting ambulation or causing any considerable maternal or neonatal adverse effect
Evaluation of A Four Stroke Compression-Ignition Engine with Load (100N).
A loaded four stroke compression ignition (Nissan Primera model) engine mounted in a heat engine laboratory of Enugu State University of Science and Technology Enugu was used for the exercise. An absorption dynamometer was attached to the engine to measure torque. As the engine was running, the speed was recorded with a digital tachometer at a time frame of 20 seconds. A lot of tests were carried out to determine a number of parameters like specific fuel consumption, mechanical efficiency, fuel mass flow rate, indicated power, brake power, brake horse power, rate of fuel consumption at different gear ratios. The data so obtained were tabulated and relationship between various parameters plotted in graphs. Results show that: volume of diesel consumed increases with increasing engine speed, increases with increasing gear; mass flow rate of diesel increases with increasing brake power, increases with increasing gear; specific fuel consumption decreases with increasing engine speed ; specific fuel consumption also decreases with increasing brake power; indicated power increases as engine speed increases. Keywords: Diesel Engine, Absorption Dynamometer, Tachometer, Engine Torque, Brake Horse Power, DOI: 10.7176/JETP/9-8-04 Publication date: November 30th 201
Design and Development of a Trapezoidal Plate Fin Heat Exchanger for the Prediction of Heat Exchanger Effectiveness
A trapezoidal plate-fin exchanger has been designed and developed, and an experimental test rig fabricated to test the plate fin heat exchanger. The heat exchanger was constructed in a 5 layer cross-flow arrangement. The length of the trapezoidal fins between the layers were 380mm and its height, thickness, top width and bottom width were 40mm, 0.5mm, 20mm, and 80mm respectively. A hot fluid test has been conducted to determine the thermo- hydraulic performance of the given heat exchanger at different mass flow rates (4.975 kg/s to 9.751 kg/s) at a hot inlet temperature of 369K. The values of the effectiveness obtained were plotted against the corresponding values mass flow rate to compare and evaluate the variation of the results. Thus, the performance of a heat exchanger with trapezoidal fins has been studied experimentally and it has been determined that: the mass flow rate of the fluids is proportional to the temperature drop of the fluids after passing through the exchanger. Also Increase in mass flow rate, increases the effectiveness of the heat exchanger. Improper insulation influenced heat transfers in heat exchanger cores and caused energy imbalance in the heat exchanger. This study suggests that the calculated effectiveness of 0.98 using trapezoidal plate fin heat exchanger result provides benchmark data to evaluate and predicts the performance of a plate-fin heat exchanger with trapezoidal fins for energy recovery application. Keywords: Heat exchanger development; trapezoidal fin, effectiveness, heat exchanger analysis; hot and cold fluids DOI: 10.7176/JETP/9-8-03 Publication date: November 30th 201
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
Knowledge, perceptions and myths regarding infertility among selected adult population in Pakistan: a cross-sectional study
<p>Abstract</p> <p>Background</p> <p>The reported prevalence of infertility in Pakistan is approximately 22% with 4% primary and 18% secondary infertility. Infertility is not only a medical but also a social problem in our society as cultural customs and perceived religious dictums may equate infertility with failure on a personal, interpersonal, or social level. It is imperative that people have adequate knowledge about infertility so couples can seek timely medical care and misconceptions can be rectified.</p> <p>We aim to assess the knowledge, perception and myths regarding infertility and suggest ways to improve it.</p> <p>Methods</p> <p>A cross-sectional survey was carried out by interviewing a sample of 447 adults who were accompanying the patients at two tertiary care hospitals in Karachi, Pakistan. They were interviewed one-on-one with the help of a pretested questionnaire drafted by the team after a thorough literature review and in consultation with infertility specialists.</p> <p>Results</p> <p>The correct knowledge of infertility was found to be limited amongst the participants. Only 25% correctly identified when infertility is pathological and only 46% knew about the fertile period in women's cycle. People are misinformed that use of IUCD (53%) and OCPs (61%) may cause infertility. Beliefs in evil forces and supernatural powers as a cause of infertility are still prevalent especially amongst people with lower level of education. Seeking alternative treatment for infertility remains a popular option for 28% of the participant as a primary preference and 75% as a secondary preference. IVF remains an unfamiliar (78%) and an unacceptable option (55%).</p> <p>Conclusions</p> <p>Knowledge about infertility is limited in the population and a lot of misconceptions and myths are prevalent in the society. Alternative medicine is a popular option for seeking infertility treatment. The cultural and religious perspective about assisted reproductive technologies is unclear, which has resulted in its reduced acceptability.</p
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