Fabrication of precise aperiodic multichannel fibre Bragg grating filters for spectral line suppression in hydrogenated standard telecommunications fibre

We demonstrate the design and fabrication of multichannel fibre Bragg gratings (FBGs) with aperiodic channel spacings. These will be suitable for the suppression of specific spectral lines such as OH emission lines in the near infrared (NIR) which degrade ground based astronomical imaging. We discuss the design process used to meet a given specification and the fabrication challenges that can give rise to errors in the final manufactured device. We propose and demonstrate solutions to meet these challenges

PERFORMANCE APPRAISAL OF TREAP AND HEAP SORT ALGORITHMS

The task of storing items to allow for fast access to an item given its key is an ubiquitous problem in many organizations. Treap as a method uses key and priority for searching in databases. When the keys are drawn from a large totally ordered set, the choice of storing the items is usually some sort of search tree. The simplest form of such tree is a binary search tree. In this tree, a set X of n items is stored at the nodes of a rooted binary tree in which some item y ϵ X is chosen to be stored at the root of the tree. Heap as data structure is an array object that can be viewed as a nearly complete binary tree in which each node of the tree corresponds to an element of the array that stores the value in the node. Both algorithms were subjected to sorting under the same experimental environment and conditions. This was implemented by means of threads which call each of the two methods simultaneously. The server keeps records of individual search time which was the basis of the comparison. It was discovered that treap was faster than heap sort in sorting and searching for elements using systems with homogenous properties.   &nbsp

Knowledge, perception and preventive practices of COVID-19 among Primary Health Care workers in Ogun State, Nigeria

Objective: This study was carried out to determine the COVID-19 knowledge, perception, and preventive practices among primary health care workers in Ogun state.Methods: A descriptive cross-sectional study was carried out among 339 primary health care workers in Ogun state using self-administered questionnaires. Knowledge of COVID-19 was graded as good with a minimum score of 75% while perception was graded as good with a score greater than the mean scores. Preventive practices were categorized as good with minimum scores of 75%. Associations between knowledge,  practice, and categorical  variables were assessed using the chi-square test with the level of significance set at p < 0.05Results: The mean age of respondents was 42.30 ± 8.73 years. The major source of information on COVID-19 was health training (99.7%). A total of 50.7% had good knowledge of COVID-19 while 42.8% had a good perception of COVID-19. The majority (92.9%) had good COVID-19 preventive practices. Length of years in service was significantly associated (p=0.024) with knowledge of COVID-19.Conclusion: About half of the health care workers had good knowledge of COVID-19 while the perception of COVID-19 was poor. However, preventive practices carried out among the healthcare workers were good. Efforts should be made to further improve the knowledge and perception of primary health care workers as they play a vital role in the delivery of health care services in the state

Assessment and Comparative Study of Radon Level in Water Samples Collected within Ogbomoso Metropolis, Oyo State, Nigeria

In the recent time, due to the unavailability of public pipe borne water which the government provides for use, the alternative uncased and cased water became the popular means of water supply, both in rural and urban areas, not minding the likely health effect that may arise due to high level of concentration of radon and its progeny in drinking water from the aforementioned sources. Hence, this study focuses on the radon concentration in underground water samples collected across Ogbomoso land. A total of 300 water samples were collected, comprising of 160 water samples from uncased and 140 samples from cased well. The samples were analysed using a well calibrated active electronic radon detector RAD7 (DURRIDGE Company Inc., USA). The results obtained revealed that the radon concentration of the uncased well is in the range of 3.30 kBqm-3 to 33.95 kBqm-3, while the radon concentration for the cased well fell in the range 30.39 kBqm-3 to 65.98 kBqm-3. The results obtained from the two categories of water samples analyzed showed that the cased well sources had the highest concentration of radon compared with the limit set by local and international bodies. Hence, appropriate measures should be taken to mitigate the level of concentration of radon in the water within the study area before consumption. Concerted effort should also be made by the health workers to enlighten the residence on the potential harmful effect of radon to human health

TEACHERS’ PERCEPTIONS OF DEVIANT BEHAVIOURS PREVALENCE IN SENIOR SECONDARY SCHOOLS IN MAINLAND ZONE TWO, LAGOS.

Deviant behaviours in schools are behaviours that do not conform to the school norms, culture, rules and regulations. This study is about the teachers’ perceptions of the prevalence of deviant behaviours among the senior secondary two students in mainland zone two. The target population was all the senior secondary teachers in Mainland zone two, with 128 males and 152 female teachers. Data was collected using a self-structured questionnaire divided into two sections. Section A comprises the demographic data, while section B has 16 items. The items had subheadings, namely deviancies due to attack on school authority, deviancies relating to attacks on persons or properties, deviancies due to student’s gang attacks and deviancies relating to the poor reading study. The study was guided by one research question and two hypotheses. Mean and standard deviations were used to analyse the data while t-testing the null hypothesis at a 0.05 level of significance. Results showed no statistically significant difference between the perceptions of male and female teachers on the prevalence of deviant behaviours in schools. Still, there was a statistically significant difference in perception based on teachers’ age group. Recommendations were made, including provisions for counsellors, and regular seminars/workshops on deviant behaviours to students, school authorities, teachers and parents

TEACHERS’ PERCEPTIONS OF DEVIANT BEHAVIOURS PREVALENCE IN SENIOR SECONDARY SCHOOLS IN MAINLAND ZONE TWO, LAGOS.

Deviant behaviours in schools are behaviours that do not conform to the school norms, culture, rules and regulations. This study is about the teachers’ perceptions of the prevalence of deviant behaviours among the senior secondary two students in mainland zone two. The target population was all the senior secondary teachers in Mainland zone two, with 128 males and 152 female teachers. Data was collected using a self-structured questionnaire divided into two sections. Section A comprises the demographic data, while section B has 16 items. The items had subheadings, namely deviancies due to attack on school authority, deviancies relating to attacks on persons or properties, deviancies due to student’s gang attacks and deviancies relating to the poor reading study. The study was guided by one research question and two hypotheses. Mean and standard deviations were used to analyse the data while t-testing the null hypothesis at a 0.05 level of significance. Results showed no statistically significant difference between the perceptions of male and female teachers on the prevalence of deviant behaviours in schools. Still, there was a statistically significant difference in perception based on teachers’ age group. Recommendations were made, including provisions for counsellors, and regular seminars/workshops on deviant behaviours to students, school authorities, teachers and parents

An Agent-based Performance Evaluation System

Performance evaluation is one of the major factors that determine the growth and development of any organization. Competent and hardworking employees are identified proper appraisal, and promotion and gratuity are justly applied. Lack of clarity of performance metrics and bias create improper appraisal in organizations, with evaluation process mostly inconclusive, incomplete, and unfair, affecting the effectiveness of the result. This study, therefore, focused on developing a model and application towards achieving a staff-centric, task-centric and environment-centric computer-based appraisal system. In developing the proposed system, the spiral model of the Software Development Life Cycle was adopted. The software development environment consists of Netbeans Integrated Development Environment, Hypertext Mark-up language, MySQL, MySQL DB connector, Apache and PHPmyAdmin. The metrics that were used by the system to evaluate performance include attendance, employee responsiveness, punctuality and projects. The model was created and an agent-based performance evaluation application was developed as an instantiation of the model. The system revealed employee strengths and weaknesses regarding execution of a particular project.

TOWARDS EFFECTIVE PLANNING, DESIGN AND MONITORING OF DAMS IN NIGERIA

Besides serving as a center of tourist attraction, creating jobs for the unemployed, a rich source of fish and a fallback in times of drought, a dam also creates electricity from nothing other than the falling of water through its turbines. In Nigeria, like in many other parts of the world, dam projects are often seen as key to economic solution through hydroelectric power supply. The technology of dam construction in Nigeria is still experimental. There are so many unknown factors in dam design, construction and operation that may affect dam’s safety and performance. Relying on field experience from various parts of Nigeria, this paper examines the essential details necessary for consideration in dam planning and design using the complete and accurate information on the important variables such as technical, environmental, socio-cultural, economic or cultural factors. The results of these examined factors indicated that most of dam projects in Nigeria are not properly planned. The basic planning flaws include hydrologic, environmental and social factors which are seen by dam builders as obstacles to be ignored, covered up or surrogated to engineering in the project planning. Incorrect calculation of flood flows has lead to dam failures and reservoir siltation has drastically reduced the lifespan of dams, making one to conclude that the entire concept of dam safety as a design criterion is a new one. It appears that Nigeria will have to live with these flaws and some of these cost for sometimes to come. There is, therefore, the need for us to reduce these through proper planning, design and monitoring of our dams. It is recommended that a comprehensive dam safety study of all old dams (i.e. ≥ 20 years) be carried out. &nbsp

Relative Impact Of Transport Infrastructure Investment On Sectoral Growth In Nigeria

Literature on the relationship between infrastructure investment and economic growth revealed divergent of results especially across sample periods and sizes, and model specifications. This study examined the relative impact of transport infrastructure investment on sectoral growth in Nigeria. Ex post facto research design was employed using annual secondary data sourced from CBN, WDI (2016). The investigation of the sectors of the Nigerian economy showed that road transport infrastructure was most significant (= 29.65291, t= 2.69504, p>0.05), with industrial sector productivity (= -0.686874, t=-1.38578, p>0.05) and agricultural sector productivity (=-0.495217, t= -0.73817, p>0.05) not exerting a significant effect on economic growth in Nigeria. It was also evident that health sector productivity (= -144.6662, t= [-2.70142, p<0.05) and education sector productivity (= -18.36868, t= -2.74476, p<0.05) exert a significant negative effect on economic growth in Nigeria at 5% level of significance. It was thus concluded that road transport infrastructure does not have a significant effect on sectoral growth in Nigeria. Hence it was recommended that the government should embark on development policies that will aim at strengthening the sub-sector of theeconomy so that it can operate in its full capacity and improve its contribution to economic growth. Literature on the relationship between infrastructure investment and economic growth revealed divergent of results especially across sample periods and sizes, and model specifications. This study examined the relative impact of transport infrastructure investment on sectoral growth in Nigeria. Ex post facto research design was employed using annual secondary data sourced from CBN, WDI (2016). The investigation of the sectors of the Nigerian economy showed that road transport infrastructure was most significant (= 29.65291, t= 2.69504, p>0.05), with industrial sector productivity (= -0.686874, t=-1.38578, p>0.05) and agricultural sector productivity (=-0.495217, t= -0.73817, p>0.05) not exerting a significant effect on economic growth in Nigeria. It was also evident that health sector productivity (= -144.6662, t= [-2.70142, p<0.05) and education sector productivity (= -18.36868, t= -2.74476, p<0.05) exert a significant negative effect on economic growth in Nigeria at 5% level of significance. It was thus concluded that road transport infrastructure does not have a significant effect on sectoral growth in Nigeria. Hence it was recommended that the government should embark on development policies that will aim at strengthening the sub-sector of theeconomy so that it can operate in its full capacity and improve its contribution to economic growth. Key words: Road transport infrastructure, Investment, Sectoral growth and Nigeri

Comparative Study on the Contribution of Asbestos and Gypsum Building Materials to Environmental Radioactivity and Its Radiological Implications

Building materials have been studied and found to contain trace amount of natural radionuclides. In order to estimate the radiological impact to the dweller, the level of radionuclides present in asbestos and gypsum building materials available in Nigeria market were carried out using a well shielded and calibrated gamma spectrometry. The results obtained shown that the natural radionuclides of 238U, 232Th, and 40K are present in the building materials assayed, with activity concentration of 141.76 to 526.29 Bqkg-1, 2.14 to 7.94 Bqkg-1 and 9.89 to 14.23 Bqkg-1 for the gypsum samples and 221.64 to 513.38 Bqkg-1, 15.99 to 34.68 Bqkg-1 and 9.10 to 18.93 Bqkg-1 for the asbestos samples respectively. The average concentration obtained for samples are relatively lower than the worldwide average. The radiation hazard indices estimated are also lower than the international recommended values. Based on the results obtained, it can be concluded that the use of these materials in construction of dwellings may be considered safe for inhabitants and that the dwellers inside the buildings are not supposed to acquire any radiological complication in terms of radiation hazard. &nbsp