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Altitudinal variation in small mammal distribution on Mountain Afadjato
No full textThe relationship between altitudinal variation and small mammal species composition, abundance and diversity was studied at Mountain Afadjato (~ 885 m) in the Volta Region of Ghana. The study focused on a test to determine if the mid-altitudinal pattern could be applied to Mountain Afadjato. Species composition, abundance and diversity were documented across four altitudinal gradients along the mountain. Forty-five Sherman collapsible live traps were used to capture small mammals in the wet and dry seasons. Two hundred and ten individual rodents belonging to four species, Praomys tullbergi, Mastomys erythroleculus, Myomys sp. and Mus minutoides were captured for a total of 2,208 trap nights. Praomys tullbergi was the most abundant species across the four altitudinal gradients. A decreasing species richness and diversity with increasing altitude pattern prevailed. Principal Component Analysis (PCA) revealed five microhabitat variables; herbaceous species density, diameter at breast height, number of holes on the ground, number of stumps,and soil temperature correlated with the distribution of small mammals
Design of direct early detection device of Apnea for Preterm babies
No full textApnea in preterm babies is the cessation of breath for a short period usually between 6-15 seconds resulting from undeveloped lungs and respiratory centre. It is the cause of most primary disorders like cerebral palsy, sensory defects and respiratory illness. Detecting and monitoring apnea in developing countries like Ghana is usually through indirect methods. These methods give results that are normally too late for the resuscitation to revive the baby. In this paper, we designed a cost effective direct apnea detecting system at a very early stage by following the engineering principles. The system comprises of a signal acquisition unit, a central processing system and a display unit, a power source and an alert system coupled with a storage functionality. The system acquired temperature using silicon bandgap sensor LM 35 and breathing rate signal using force sensitive resistor FSR. The breathing rate signal was analyzed using MATLAB. The system followed an operational logic which is incorporated into the programming of the microcontroller. A prototype of the device was fabricated, with wood used as the casing. The device was tested on a normal adult and the temperature and breathing rate were displayed on an LCD screen
Design of Kangaroo Mother Care Device with Integrated Vitals Monitoring Systems as Alternative to Incubators
No full textPrematurity kills more than 8000 babies annually in Ghana since the organs of these babies are often underdeveloped which renders them vulnerable to various infections. In order to save the lives of these babies, they are often placed in incubators. In situations where incubators are not available, a kangaroo mother care (KMC) approach is employed. The traditional KMC lacks means of monitoring vitals such as the temperature, SPO2 level, heart rate and blood pressure of these preterm babies. The practice of the KMC might also pose some inconvenience to the mother since part of the body is exposed. In this project, we integrated the traditional KMC with electronic vitals monitoring system and also addressed the problem of inconvenience of part of the body exposure of the parent practicing KMC. The engineering design process was followed and a functional mockup was constructed. The mockup was tested by comparing the results generated to the results of an existing calibrated devices and the error margins were calculated as 0.62, 0.52, 0.41 and 0.34 for blood pressure (BP), heart rate (HR), temperature and SPO2, respectively. This device could be an alternative option to baby incubators
Impact of labour productivity factors on construction project cost and time
No full textProductivity is the dominating aspect in construction as it encourages cost savings and effective utilization of resources. Poor labour productivity is one of the major causes of cost and time overrun in construction projects and as such requires attention. Previous studies have identified factors affecting labour productivity within building projects, however, there is need to understand these factors as it relates to their impact on cost and time. In view of this, the paper aimed at assessing the impact of factors affecting labour productivity on cost and time, with a view to minimizing their effects on construction projects. The study elicits knowledge gained by project managers actively engaged in construction projects within Abuja been the Federal Capital Territory and employed the use of a survey. A well-structured questionnaire was designed to collect data with respect to degree of impact of labour productivity factors on construction project cost, and time using a five-point Likert scale and distributed to 45 project managers using purposive sampling. Responses from the administered questionnaires were collated, interpreted, and analysed using descriptive statistics, and results presented in tables. The findings showed that material shortage at project site with a mean value of 3.68 had significant impact on construction project cost. Furthermore, lack of tools and equipment in the market, and workforce absenteeism with mean values of 3.65 and 3.62 respectively had significant impacts on construction project time. The study concludes that material shortage, lack of tools and equipment in the market, and workforce absenteeism are labour productivity factors that had significant impact on construction project cost and time. Thus, Construction managers should enforce the use of material supply schedule, and adopt appropriate financial incentives for employee’s that could curtail the problem of absenteeism
Impact of Craftsmen’s Mode of Employment on Performance in Selected Construction Firms in Lagos State, Nigeria
No full textThe quest to improve productivity of workers and overall performance of construction projects has necessitated the need to examine various categories of workforce and their overall effect on project success. The study investigated construction employment with a view to evaluating their impact on the performance of craftsmen in selected construction firms. The categories of employed craftsmen considered were the permanent, casual, hiring and firing, short-term and part-time. Performance parameters considered were technical experience; workmanship quality; time; and accidents recorded on sites. The craftsmen were drawn from three main trades: bricklayers (blocklaying/bricklaying, concreting, plastering, flooring); carpentry (roofing, timber formworking and scaffolding) and iron fixing (steel work and iron bending). A pilot survey was conducted to determine performance variables through questionnaire administered on thirty (30) experts drawn from selected firms. The experts were: human resources managers; construction managers; site engineers; supervisors and foremen who are directly involved with the employment and work activities of the craftsmen. The study revealed an employment composition of 48% permanent craftsmen, 35% casual while 17% were other staff of the companies studied. The results of employment practices indicated that 55% of the companies used primary six with trade test and 21% used senior secondary school as qualifications for the employment of craftsmen while the remaining companies used other qualifications. With p values of .001 and .047 respectively, the crosstab analysis of the impact of employment categories on craftsmen's performance revealed that there were substantial correlations between casual employment and the frequency of accident and technical performance
Modelling the Adsorption of Arsenic from Water and Wastewater using Microsoft Excel Solver and SPSS
No full textArsenic (As) poisoning is toxic to human organs and tissues (the heart, bones, intestines, kidneys, and reproductive and nervous systems). This paper focused on the modelling fittings of removal of As from water and typical industrial wastewaters through adsorption. Equilibrium isotherm parameters were determined using Microsoft Excel Solver (MES) and SPSS methods. The study revealed that equilibrium isotherms for As adsorption from aqueous solutions can be grouped into two based on the values of correlation coefficient (R2) as follows: adsorption equilibrium isotherms with R2 greater than 0.95 and R2 less than 0.95. Microsoft Excel Solver method was found to be as accurate as SPSS method based MSC, CD, R and AIC. The study concluded that MES can be used for model fitting based on accuracy and cost (at no additional cost of purchase and installation unlike SPSS)
Impact of Waste Foundry Sand as a Partial Substitute for Sharp Sand on Compressive Strength and Water Absorption of Hollow Sandcrete Block
No full textThe need for habitable and affordable shelter cannot be overemphasized but the high cost of components of shelter such as hollow sandcrete blocks, bricks etc. posed a challenge to our ability to access affordable and habitable shelter. Utilization of already discarded waste foundry sand (WFS) as eco-friendly construction material for production of hollow sandcrete blocks, will save cost and preserve our environment. In this study, impact of locally available waste foundry sand as partial substitute for sharp sand in production of hollow sandcrete blocks was investigated. Sharp sand was partially substituted with WFS at 0, 10, 20 and 30%. A mix ratio of 1:6 (ratio of cement to sharp sand) and a water-cement ratio of 0.5 were used. Hollow sandcrete blocks were subjected to compressive strength tests at 7th and 28th days as well as a water absorption test on the 28th-day. Outcomes of the research showed that an increase in the amount of WFS led to the loss of compressive strength across all curing ages, and that all sandcrete block samples including control samples did not satisfy the minimum 28th day strength requirement of 3.5 MPa stipulated for load-bearing hollow sandcrete blocks. However, block samples containing 0 and 10% of WFS can satisfactorily be used for the construction of non-load bearing walls since they meet the required minimum strength of 1.5 MPa at 28th day. It was also observed that increasing the quantities of WFS from 0 – 30% caused a corresponding increase in the water absorption for all the block samples although the recorded values did not exceed the recommended maximum of 12% except for samples containing 30% WFS. Conclusively, WFS has a negative impact on both compressive strength and water absorption properties of sandcrete blocks and as such cannot serve as a good partial substitute for sharp sand
Evaluation of Risks Involved in Housing Projects Procured by Public Private Partnership in Kebbi State, Nigeria
No full textStudies have shown that the adoption of Public Private Partnership (PPP) system which is expected to enhance the provision of affordable housing with diverse arrays of benefits, have failed to accomplish this task due to hindrances from several risk factors. The study evaluated the risks involved in housing projects procured by PPP in Kebbi State with a view to providing better housing delivery. Data were collected using questionnaire administered on professionals in 25 construction firms registered with the Kebbi State Ministry of Land, Housing and Urban Planning, and 15 purposively selected occupiers of PPP housing projects. Analysis of data was undertaken with the use of Mean Item Score (MIS) and Relative Importance Index (RII). The study revealed that the most important reason for the adoption of PPP procured housing projects was “Reduction in the size of inefficient bureaucracy” (RII = 0.87); the most critical risk associated with PPP procured housing projects was “Completion Risks” (MIS = 4.12); the factor leading to the success of PPP housing projects with the highest value was “Stable economic system” (MIS = 4.52; average MIS = 3.96), thus implying that the projects were successful; and Occupiers were satisfied with the conditions surrounding the Gesse Phase I and Phase II PPP Housing Estate in Birnin Kebbi, Kebbi State (MIS = 3.68 and 3.60 respectively). It was concluded that the risks involved in PPP housing projects in Kebbi State are fairly critical and can be effectively managed by adopting the drivers of the success of PPP projects and preventing the occurrence of the barriers to the success of PPP projects in Kebbi State, Nigeria. The major recommendation from the study was that the Government should focus more attention on implementing the strategies of “Stable economic system”, and “Avoidance of bribery and corruption among contracting parties”, so as to mitigate the barriers to the success of PPP housing projects in Kebbi State, Nigeria
Women’s leadership in Ethiopian higher education: development, contribution, quality and preference
No full textWomen are underrepresented in higher education leadership across the world and Ethiopia is no exception. Although women leadership in Ethiopian higher education is a relatively new practice, its development has not been well examined. The present paper aims to address this lacuna by examining women senior leadership development, contribution, quality and preference based on the views and experiences of twelve women senior leaders drawn from ten public universities. The participants are current and past vice presidents at public universities of different generations and types. The results indicate that although women have made significant progress in gaining senior leadership positions, senior leadership remains to be a men's club where women are rarely invited. The results also reveal that women have perceived leadership quality and contributions. The findings show that among the various senior leadership positions women prefer and assume a research and community service vice president position and this goes to the extent of associating this position with women. The results suggest that enhancing women leadership development requires providing training, mentoring and other opportunities specifically aimed at advancing women to senior leadership positions, and ensuring sustainability of women leadership development programs
The leadership and supervisory practices of principals in public secondary schools of the State of Amhara, Ethiopia, as perceived by teachers
No full textThis study aimed at examining the leadership and supervisory practices of secondary school principals in the State of Amhara in view of teachers. It investigated the leadership factors that attributed for poor education quality. To that effect, the leadership and supervisory practices of principals were examined. The study employed the descriptive survey research design of the quantitative approach involving 1115 teachers recruited through a proportionate stratified random sampling technique. Data collected through a questionnaire and analyzed using descriptive statistics and multivariate analyses of variance revealed that teachers perceived the leadership and supervisory practices of principals were weak. Teachers have very weak differences in terms of three demographic factors, except sex which has no difference at all, regarding their poor leadership practices. Regarding supervisory practices, qualification level demonstrated a weak difference, the rest three with no significant differences. In addition, teachers’ acknowledgment of the supervisory role of their principals is inversely correlated to the qualification level former, despite the weak difference. That is, the higher teachers’ qualification level the less they acknowledge the supervisory role of their principals. The findings also revealed that leadership and supervisory practices of principals are correlated positively and significantly. Such a perception may have far-reaching consequences on the commitment and effectiveness of teachers and the quality of education. Therefore, the assignment of principals needs to be based on competence to foster commitment and ownership among all parties. In addition, further research that triangulates data from students, principals, and other stakeholders through different methods shall be conducted to resolve leadership-related limitations in secondary schools