Ophthalmic disorders among students of School for the Deaf

Aim: This study aimed at determining the prevalence and pattern of ophthalmic disorders amongstudents of School for the Deaf, Akure, Ondo State, Nigeria.Methodology: This is a cross sectional descriptive study was conducted in October, 2011 aspart of activities marking the Annual Physicians’ week of Nigerian Medical Association (NMA),Ondo State. Ethical clearance was obtained from the Ethical Review Committee of FederalMedical Centre, Owo prior to commencement of this study. The permission of the SchoolAuthority was also obtained before the commencement of this study. The respondents wereselected by simple random sampling technique. All enrolled participants were interviewed withthe aid of the study instrument (questionnaire) by the authors and interpreters (school teachers).Results: The respondents comprised of 91(56.9%) Males and 69 Females (43.1%). Nearly all therespondents;158(98.8%) were deaf and dumb. Most respondents; 116(72.5%) had ocularexamination in the past. Few respondents; 118(73.75%) had ophthalmic disorder. The commonest ophthalmic disorder was refractive error which was found in 16 respondents(38.1%). Myopia was diagnosed in 9 respondents.CONCLUSION: Most of the respondents were deaf and dumb. Few respondents hadophthalmic disorder. The commonest ophthalmic disorder was refractive error. Myopia was themost predominant refractive error. There is need for periodic ocular screening and treatment atthe School for the Deaf.

Analysis of RSVP-TE graceful restart

GMPLS is viewed as an attractive intelligent control plane for different network technologies and graceful restart is a key technique in ensuring this control plane is resilient and able to recover adequately from faults. This paper analyses the graceful restart mechanism proposed for a key GMPLS protocol, RSVP-TE. A novel analytical model, which may be readily adapted to study other protocols, is developed. This model allows the efficacy of graceful restart to be evaluated in a number of scenarios. It is found that, unsurprisingly, increasing control message loss and increasing the number of data plane connections both increased the time to complete recovery. It was also discovered that a threshold exists beyond which a relatively small change in the control message loss probability causes a disproportionately large increase in the time to complete recovery. The interesting findings in this work suggest that the performance of graceful restart is worthy of further investigation, with emphasis being placed on exploring procedures to optimise the performance of graceful restart

Designing a multi-hop regular virtual topology for ultrafast optical packet switching : node placement optimisation and/or dilation minimisation?

This paper studies the design of multi-hop regular virtual topologies to facilitate optical packet switching in networks with arbitrary physical topologies. The inputs to the virtual topology design problem are the physical topology, the traffic matrix and the regular topology. In this paper, this problem is tackled directly and also by decomposition into two sub-problems. The first sub-problem, dilation minimisation, uses only the physical topology and the virtual topology as optimisation inputs. The second sub-problem considers the traffic matrix and virtual topology as optimisation inputs. The solutions of these two sub-problems are compared with each other and against the results obtained when the global problem is optimised (using all three possible input parameters) for a variety of traffic scenarios. This gives insight into the key question of whether the physical topology or the traffic matrix is the more important parameter when designing a regular virtual topology for optical packet switching. Regardless of the approach taken the problem is intractable and hence heuristics must be used to find (near) optimal solutions in reasonable time. Five different optimisation heuristics, using different artificial intelligence techniques, are employed in this paper. The results obtained by the heuristics for the three alternative design approaches are compared under a variety of traffic scenarios. An important conclusion of this paper is that the traffic matrix plays a less significant role than is conventionally assumed, and only a marginal penalty is incurred by disregarding it in several of the traffic cases considered

The Homotopy Analysis of Unsteady Hydromagnetic Flow of a Viscous Fluid with Oscillatory Suction Velocity

This work considered the unsteady hydromagnetic flow of an electrically conducting, incompressible, viscous fluid past an infinite vertical porous plate. The oscillatory suction velocity is normal to the plate. The uniform magnetic field influence is normal to the flow and the permeability of the medium is time dependent. The oscillatory suction velocity was defined so as to eliminate any complexity in the equations that were derived. The problem was solved using a modified technique of the Homotopy analysis method. The results obtained were discussed for various effects of material parameters on the velocity, temperature and concentration profiles.Keywords: Heat transfer, Mass transfer, Oscillatory suction velocity, Hydromagnetic flow, Vertical porous plat

RSVP performance optimisation using multi-objective evolutionary optimisation

The proposed uses of the resource reservation protocol (RSVP) now extend beyond reserving resources in Internet Protocol (IP) networks to being a generic signaling protocol for generalised multi-protocol label switching (GMPLS). In any implementation of RSVP, there are a number of discretionary timing parameters, the values of which affect the efficacy of RSVP in establishing and maintaining reservations/connections. This work frames the interactions between key RSVP timing parameters and performance metrics as a multi-objective optimisation problem which, due to its intractable nature, is tackled using a reputable multi-objective evolutionary algorithm. It is shown that this approach is a feasible means of exploring many of the innate tradeoffs in soft-state protocols such as RSVP. This approach facilitates an extensive comparison of a number of variants of RSVP: standard RSVP, RSVP featuring the recently standardised retransmission algorithm and two subsequent variants of this algorithm, supporting the asymmetric delivery of RSVP control messages. These RSVP variants are compared in terms of multiple performance metrics under a number of different exemplar network conditions, giving insight into their relative merits. Furthermore, the relative significance of the different timing parameters is investigated and their most expedient values determined

Dynamic Performance Analysis of Cogeneration Potential in Photovoltaic Power System.

The solar cell junction is susceptible to performance degradation, due to internal temperature rise which is further perturbed by ambient temperature rise. The conversion efficiency of the solar module remarkably drops because of temperature rise. The diurnal module temperature hovers above 60 degrees C. It is possible to keep the conversion efficiency high by water-cooled or air blast equipment. This project is a preliminary study of the impact of temperature variation across seasons on the dynamic performance of photovoltaic power system. The photovoltaic (PV) module was mounted on a test rig at latitude 7 degree on top of physics building Obafemi Awolowo University campus. The output voltage of the PV module was applied to a resistive load and system efficiency performance measured over a period of time covering the dry and rainy seasons. Measurements of ambient temperature, PV junction operating temperature, wind speed, solar irradiance, and power delivered were carried out. A numerical algorithm was developed to analyse the data. The transport medium can store heat energy from the solar module, so that a large amount of hot water can be produced. The results show that this thermal transfer benefit, positions the PV system in good stead, for Microgrid: Cogeneration Energy Efficiency functionality. Keywords: Conversion efficiency, Photovoltaic power system, PV module, Water-cooled equipment, Cogeneration

Demographic and clinical profile of patients with juvenile onset open angle glaucoma in southwestern Nigeria

Background: This was a non-comparative, retrospective review of patients diagnosed with juvenile open angle glaucoma (JOAG) in the eye clinic of a tertiary hospital in southwestern Nigeria.Objective: To document the demographic characteristics, clinical features and treatment outcome of the patients diagnosed with JOAG.Materials and Methods: Data were extracted from the clinical record of patients diagnosed with JOAG in the eye clinic of the University College Hospital, Ibadan, Nigeria, between January 2001 and December 2005. Such data included the basic demographic data, the clinical characteristic of the patients and the outcome of their treatment.Results: Twenty-nine patients were reviewed, which represents 3.4% of all newly diagnosed glaucoma patients seen in the out-patient section of the eye clinic of the University College Hospital, Ibadan, over the period reviewed. Eight (27.6%) patients were aged 20 years and below. The mean age was 25.1 ± SD 6.0 years. Eighteen (62.1%) had visual acuity of 6/18 or worse in the better eye at the time of presentation. The mean intraocular pressure (IOP) of the patients at presentation was 32.3 ± SD 15.2 mmHg. Eight (27.6%) patients defaulted within 6 months of presentation. The mean IOP for the 21 patients who were followed up on treatment for a mean period of 9.6 months was 17.0 ± SD 6.0 mmHg.Conclusion: Most patients with JOAG in this review presented with advanced form of the disease. Early detection through parent-driven school eye health program and community-based case detection could help in reducing the scourge arising from JOAG among our population

Photovoltaic Generating System Parameter Sizing for Building

Small to medium sized battery storage required to address the intermittency challenge of the energy of solar radiation could be achieved by appropriate sizing of the photovoltaic system parameters like photovoltaic module (PVM) number and battery capacity. This paper presents the results of evaluation of the optimum parameter values in sizing of stand-alone photovoltaic (PV) system that satisfies building energy demand, with almost zero Loss of Power Supply Probability (LPSP). A time step simulation of system performance based on energy balance for various combinations of PV numbers and battery capacities was employed. (Three seasons of operation were considered; rainy, hot and hot/dry). The rainy season result indicating high storage capacity requirement of about (2500-Ah), is of highest cost compared to other seasons. Stand-alone photovoltaic system size that will assuage the intermittency challenge; mitigate peak demand costs and provide near zero LPSP was determined. Keywords: loss of power supply probability, photovoltaic, energy demand, parameter sizing, stand-alon

ANTHROPOMETRIC EVALUATION OF A UNIVERSITY LECTURE HALL’S SEAT

Ergonomics deals with the methods and processes of designing workplaces so that they fit the individuals that make use of them. This paper focuses on the anthropometric evaluation of the lecture hall’s seat of a University. Two anthropometric dimensions, the popliteal height (PH) and the buttock-popliteal length (BP) of 188 undergraduate students using the University lecture hall were taken. The lecture hall’s seat has height of 465mm and depth of 405mm. It was found that 61% of the student population used for the study was in the fit range of the seat height. Examining the seat depth and buttock to popliteal length, it was observed that 53.7% of the students may be comfortable using the present seat depth design of 405mm dimension, while over 46% of the students’ population used for the study might not be able to utilize the backrest of the seat. From this study, it was found that the seat depth of the University lecture hall’s seats were not adequate and a model should be developed to determine the most appropriate seat depth required for the University’s lecture hall’s seats. &nbsp

Schistosomiasis presenting as acute appendicitus

No Abstract.The East African Medical Journal Vol. 83 (10) 2006: pp. 528-53