23 research outputs found
Experimental Analysis of Cable Distance Effect on Signal Attenuation in Single and Multimode Fiber Optics
Losses during transmission and high demand of high data rate by the end users have become the biggest challenges facing the telecommunication industries worldwide with Nigeria inclusive. Fiber optic cable as a channel of communication has been adapted worldwide in solving these problems but there is a little limitation in the place of multimode fiber in long distance communication. This paper focuses on the effect of changes in distance on transmitted bandwidth on single mode and multimode fiber. Two cases were considered during this research; (a) with optical amplifier placed in between multimode fiber and (b) without optical amplifier in between multimode fiber. Readings were taken at various distances when specific bandwidth ranging from 50Mbps to 500Mbps was transmitted from the base station to the various distances and it was observed that there was no significant changes in bandwidth received at specified distances (100, 200, 300, 400, 500 etc) m when using single mode fiber, there was a drastic reduction in bandwidth when it get to a distance of 300m when using multimode. When optical amplifier was placed in between the multimode fiber at some selected distances after 400m from the transmitting BTS, it was noticed that the drastic reduction in transmitted bandwidth was almost eliminated, thereby proven that multimode fiber can be use in long distance communication provided optical amplifiers are incorporated in between the distance to bust the signal strength
Design and Implementation of a Single-Phase Energy Meter with SMS Controlled and Monitored Recharge Capability
The Nigerian power sector is faced with poorly organized billing and consumer relations management. Tariff billing and
collection has been a big problem in some community in Nigeria even with the introduction of prepaid meters. The process of payment is
cumbersome and stressful as consumers have to go and pay in banks and then take tellers to power utility office to confirm their
power bills payment before they can recharge their cards. The major purpose of this work is to design and implement a convenient,
cashless, automated and transparent electricity metering, billing and payment system. This project combines the power electronic
meter with a communications network which in this case is a GSM (global system for mobile) network. Remote electricity billing is a
unique concept, in which the electricity board can collect the consumed units’ data from consumer on mobile phone using GSM
network. A unique property of this system is that, the electricity board can disconnect or reconnect consumers from remote location
through the mobile phone. As this project works on GSM network, the system can be controlled from any part of the countr
Design and Analysis of a Broadcast Network Using Logical Segmentation
This study shows how the network performance of a flat switch network in the main library complex of Ambrose Ali University (AAU), Ekpoma can greatly be improved by logical segmentation. A survey of the flat switch network of the library complex was carried out to ascertain the physical and logical topology of the network and the number of hosts and network devices available. The kind of traffic
transmitted over the network was also considered. Riverbed Modeler Academic Edition was used to simulate two replicas of the library network. One of the simulated networks was logically segmented by implementing Virtual Local Area Network (VLAN). Statistics like traffic dropped, traffic forwarded, traffic received, broadcast traffic dropped and traffic sent in bits/sec or packets/sec were collected from both simulations and the results were analyzed and compared. The results from the simulations showed that the application of VLAN immensely enhanced the network performance by about 75%(depending on the size of the network) because the logical segmentation increased the number of broadcast domain while reducing each of the broadcast size. This further implied that poor network design and large broadcast
domain in a network, gravely affect the performance of a network
Discovery of underground argon with low level of radioactive 39Ar and possible applications to WIMP dark matter detectors
We report on the first measurement of 39Ar in argon from underground natural
gas reservoirs. The gas stored in the US National Helium Reserve was found to
contain a low level of 39Ar. The ratio of 39Ar to stable argon was found to be
<=4x10-17 (84% C.L.), less than 5% the value in atmospheric argon
(39Ar/Ar=8x10-16). The total quantity of argon currently stored in the National
Helium Reserve is estimated at 1000 tons. 39Ar represents one of the most
important backgrounds in argon detectors for WIMP dark matter searches. The
findings reported demonstrate the possibility of constructing large multi-ton
argon detectors with low radioactivity suitable for WIMP dark matter searches.Comment: 6 pages, 2 figures, 2 table
Performance and Yield Assessment of Grid – Connected Solar Photovoltaic (PV) Dispersed Generation in Nigeria
 The problem of Renewable Dispersed Generation (RDG) and renewable resource harnessing in most cases, is not the inadequacy in resource distribution at a particular location, but rather the perpetually deprived exploitation of these resources. The existing dread for the performance of distributive generation systems that utilize renewable source for power generation has crippled generation expansion in most parts of Nigeria for several years. This study is therefore aimed at performing a practical assessment on the productivity of solar PV systems in Nigeria. In this study, five states with diverse geographical or meteorological data were selected from the cardinal regions of the country to include Sokoto State in North West, Borno State in North East, Ogun State in South West, Rivers State in South East and Abuja, the Federal Capital Territory at the center. The global horizontal radiations available from the National Aviation and Space Agency, NASA for these cities were used in simulating the performance of a 1- MW grid-tied solar PV plant using the PVsyst software. PVsyst simulation findings revealed that the performance parameters with respect to energy production favor the cities in the northern region more than the cities in the southern region with capacity factors decreasing from 20.46% in the northern region to 16.21% in the southern region for a 1- MW solar PV plant located in these regions. This was seen to reflect on the corresponding annual energy yield of similar systems sited in these locations. Also, the performance ratios of these systems given their respective reference yields were observed to be better in the southern region than the northern region of Nigeria, this could be attributed to external factors that can influence system efficiency. These factors tend to favor the systems located at the southern region better than those at the northern validating this study as a decision tool for the predictability of the performance of any Renewable Dispersed Generation, RDG systems utilizing solar energy at other regions of the country
A Review of the Applications of FACTS Devices on Nigerian 330 kV Transmission System
This research presents a critical review of the application ofF ACTS devices into the Nigerian 330 kV
network for the enhancement of bus voltages and the minimization of the transmission system power loss.
Available publications were critically examined with references to show these devices have been applied to
power systems. This research provides vital information for power system operators and researchers on how
to incorporate FACTS devices into the Nigerian power transmission system