Cognitive radio-enabled Internet of Vehicles (IoVs): a cooperative spectrum sensing and allocation for vehicular communication

Internet of Things (IoTs) era is expected to empower all aspects of Intelligent Transportation System (ITS) to improve transport safety and reduce road accidents. US Federal Communication Commission (FCC) officially allocated 75MHz spectrum in the 5.9GHz band to support vehicular communication which many studies have found insufficient. In this paper, we studied the application of Cognitive Radio (CR) technology to IoVs in order to increase the spectrum resource opportunities available for vehicular communication, especially when the officially allocated 75MHz spectrum in 5.9GHz band is not enough due to high demands as a result of increasing number of connected vehicles as already foreseen in the near era of IoTs. We proposed a novel CR Assisted Vehicular NETwork (CRAVNET) framework which empowers CR enabled vehicles to make opportunistic usage of licensed spectrum bands on the highways. We also developed a novel co-operative three-state spectrum sensing and allocation model which makes CR vehicular secondary units (SUs) aware of additional spectrum resources opportunities on their current and future positions and applies optimal sensing node allocation algorithm to guarantee timely acquisition of the available channels within a limited sensing time. The results of the theoretical analyses and simulation experiments have demonstrated that the proposed model can significantly improve the performance of a cooperative spectrum sensing and provide vehicles with additional spectrum opportunities without harmful interference against the Primary Users (PUs) activities

Timely and reliable packets delivery over Internet of Vehicles (IoVs) for road accidents prevention: a cross-layer approach

With the envisioned era of Internet of Things (IoTs), all aspects of Intelligent Transportation Systems (ITS) will be connected to improve transport safety, relieve traffic congestion, reduce air pollution, enhance the comfort of transportation and significantly reduce road accidents. In IoVs, regular exchange of current position, direction, velocity, etc., enables mobile vehicles to predict an upcoming accident and alert the human drivers in time or proactively take precautionary actions to avoid the accident. The actualization of this concept requires the use of channel access protocols that can guarantee reliable and timely broadcast of safety messages. This paper investigates the application of network coding concept to increase content of every transmission and achieve improved broadcast reliability with less number of retransmission. In particular, we proposed Code Aided Retransmission-based Error Recovery (CARER) scheme, introduced an RTB/CTB handshake to overcome hidden node problem and reduce packets collision rate. In order to avoid broadcast storm problem associated with the use of RTB/CTB packet in a broadcast transmission, we developed a rebroadcasting metric used to successfully select a vehicle to rebroadcast the encoded message. The performance of CARER protocol is clearly shown with detailed theoretical analysis and further validated with simulation experiments

Numerical Study of the Thermal Efficiency of a School Building with Complex Topology for Different Orientations

In this work a numerical model that simulates the thermal behavior of a building with complex topology and evaluates the indoor thermal and air quality, in transient conditions, is used for a school building thermal project. The program calculates the building surfaces solar radiation field, the building's temperatures, the internal environmental variables, and the occupant's comfort levels. Initially, after the numerical model is validated, the software is used to evaluate the school building's thermal response for four different orientations, either in winter or summer conditions. The work then aims to identify uncomfortable spaces in order to propose, as an example, several solutions that could be introduced for each orientation, that would improve the thermal comfort and air quality levels to which the occupants are subjected, and decrease the building's energy consumption levels. The information obtained from this study could be used to help a designer choose which thermal systems and solutions function best for a preferred school building orientation

Investigation of Possible Groundwater Contamination from Septic System Siting in Port Harcourt, Nigeria

The purpose of this study was to investigate the effect of siting of septic systems on the quality of groundwater in the immediate vicinity. Water samples were collected randomly from twenty (20) boreholes located less than 30m from septic systems in Port Harcourt, Nigeria to determine their physico-chemical qualities and microbiological characteristics. Standard analytical techniques were employed in the investigation. Five (5) boreholes at distances ranging from 60m to 100m from the nearest septic system were sampled for analyses as controls.  The water temperature, dissolved oxygen, turbidity and total dissolved solid values were within the World Health Organisation (WHO) standards. The pH of water from all the boreholes including the controls were lower than the WHO standards.  The values of the physico-chemical parameters obtained for water samples from boreholes located less than 30m were similar to the values obtained from control boreholes.  These physico-chemical parameters were invariably not a function of the location of the borehole in relation to septic system. The total coliform bacteria concentration ranged from 130 MPN index/100ml to 172 MPN index/100ml while the faecal coliform distribution ranged from 14 MPN index/100ml to 36 MPN index/100ml. Going by WHO standards on total and faecal coliforms, the studied boreholes and controls are all polluted. However, total Coliform and faecal coliform are found in all the control boreholes. The presence of these coliforms in borehole located close to septic systems cannot be specifically said to have come from the septic system. Keywords: Borehole, septic system, advection, dispersion, diffusion, coliform, contamination

A Survey of the Legal Framework for the Control of Oil and Gas Pollution from Some Selected Countries *

This study undertakes a comparative study of the legal framework for environmental protection in some oil and gas producing jurisdictions. Some jurisdictions were selected for this purpose. The legal framework for the prevention and control of oil and gas pollution in these countries will be compared with the position in Nigeria. The study aims at analyzing the efficacy or otherwise of the extant Nigerian statutory framework vis-a vis that of some jurisdictions with respect to the control of oil and gas pollution .The study makes a case for an effective and adequate comprehensive body of legislation to deal with oil and gas pollution as against the present situation of fragmented and often conflicting laws that are unable to deal with the problem in Nigeria. Keywords: Oil and Gas Pollution, Prevention and Control, Accross Countries of the World

International Law and the Prevention and Control of Oil and Gas Pollution

The threat of environmental problem concerns the whole world at the global level. This is because the global environment is one while the national boundaries, which have demarcated the world into distinct nations, are manmade. The features of the world’s environment, ie land, air and water, and their susceptibilities are no respecter of those national boundaries made by man in his enterprise of building sovereign States. The implication of the exploitation of oil in both onshore and offshore locations is that pollution may occur in such a way as to affect shared water resources beyond national boundaries. When this happens, it becomes an international law concern. This is why the world environment has come to be regarded as common resource. There are international conventions on the environment relevant to the control of oil and gas pollution, to which Nigeria is a signatory. The researcher aims at appraising the usefulness of these conventions in the control of oil and gas pollution in Nigeria. The study depicts that the applicability of these conventions in Nigeria is limited by the fact that they are not binding on Nigerian courts but merely persuasive in that the Constitution of the Federal Republic of Nigeria, 1999 excludes the enforceability of such Conventions in Nigeria except they have been domesticated as national laws. The study makes a case for enforceability and bindingness of international conventions in Nigeria by their being enacted  as Acts of the National Assembly in line with the provisions of the Constitution of the Federal Republic of Nigeria, 1999, as amended

A cross national survey of the legal framework for the protection of casual work arrangements in some selected countries

Nonstandard and casual work arrangements are paradigms shift from standard work arrangement which require special legal protection. This arrangement is prevalent in most developing countries as a result of high unemployment rates which has bedeviled their economies. Other factors like globalization, the shift from the manufacturing sector to the service and informal sectors and the spread of information technology have created a new economy which demands flexibility of legal arrangements in the workplace. Nonstandard or casual employment relationship is a worldwide phenomenon that cuts across various jurisdictions, genders and professions. This paper undertakes a comparative study of the legal framework of the protection of these categories of workers in Nigeria and some selected jurisdictions. The paper aims at analyzing the efficacy or otherwise of the extant Nigerian statutory framework in relation to those of other jurisdictions. The paper makes a case for an effective and adequate comprehensive body of legislation to deal with the precarious legal position of such workers.Keywords: Casual Work Arrangement, Labour, Protection, Legal Framewor

Control of pollution arising from oil and gas industry: appraising the scope of provisions under the 1999 Nigerian Constitution

Environmental issues came to the front burner in Nigeria in the 1980s upon the advent of the dumping of toxic waste by an Italian businessman at a farm in the port town of Koko in the Delta State of Nigeria. Furthermore, oil exploration and exploitation in Nigeria leaves on its trail a catalogue of environmental devastation and degradation. This has occasioned a wave of militancy and unrest in the Niger delta area of Nigeria. The situation is worsened by the paucity of the legal framework for environmental protection in Nigeria. This paper appraises the provisions for environmental production under the 1999 Nigerian Constitution with a view to ascertaining the extent of protection they afford environmental rights. It examines the provisions for environment protection in the constitution of some selected countries in order to engender a comparative insight. The paper makes a case for the entrenchment of environmental rights as enforceable rights under the Nigerian Constitution.Keywords: Control of Pollution, Oil and Gas, Nigerian Constitution, Appraisa

Determination of physicomechanical properties of velvet bean (Mucuna pruriens) from South Eastern Nigeria

Selected physical and mechanical properties of velvet bean (Mucuna pruriens) were studied at two moisture content levels of 13% and 20% (db). Compression strength characteristics were conducted under quasi-static compressive force at longitudinal and latitudinal (lateral) loading positions and the rupture forces, compressive strength, modulus of deformability, toughness, stiffness and force at bio-yield point determined as the mechanical properties at varying loading positions. Results indicated that volume (7.398 - 9.416 mm3), surface area (73.289 - 111.782 mm2), geometric mean diameter (9.18 - 11.68mm), and weight (0.872 - 1.055 g) of the velvet bean seed increased linearly with increase in moisture content. Also, the bulk density, specific gravity (0.118 - 0.112 g/mm3), sphericity (0.737 - 0.704) and aspect ratio (0.776 - 0.719) decreased linearly with increase in moisture content. These indicate that Velvet beans have wide size ranges and no single sample of the grains can effectively represent the other. In the case of the force-deformation characteristics, result indicates that the force and corresponding deformation to rupture of velvet bean seeds were found to vary from 525N, 5mm in longitudinal loading position to 800N, 7mm in lateral loading position at 13% moisture content and 131.25N, 3mm in longitudinal loading to 237.5N, 4.75mm in lateral loading at 20% (wb) moisture content. The bio-yield force, compressive strength, stiffness and toughness of the velvet bean seeds varied from 375 N, 14.412 N/mm2, 105 N/mm and 354.836 J/mm3respectively in longitudinal loading position to 475 N, 21, 961 N/mm2, 114. 286 N/mm2 and 756.961 N/mm2respectively in lateral loading position at 13% moisture content and 112.5N, 3.53N/mm2, 43.75 N/mm and 41.817 J/mm3respectively in longitudinal loading and 175 N, 6.388 N/mm2, 50 N/mm and 119.809 J/mm3respectively in lateral loading at 20% (wb) moisture content. Generally, the compressive strength of the velvet bean seeds is higher at lateral loading position than at the longitudinal loading position.Key Words: Physical Properties, Mechanical Properties, Velvet Bean, Moisture content, Loading Positions

An appraisal of the scope of provisions under the 1999 Nigerian constitution for the control of pollution arising from the oil and gas industry

Environmental issues came to the front burner in Nigeria in the 1980s upon the advent of the dumping of toxic waste by an Italian businessman at a farm in the port town of Koko in the Delta State of Nigeria. Again, oil exploration and exploitation in Nigeria leaves on its trail a catalogue of environmental devastation and degradation. This has occasioned a wave of militancy and unrest in the Niger delta area of Nigeria. The situation is worsened by the paucity of the legal framework for environmental protection in Nigeria. This paper appraises the provisions for environmental protection under the 1999 Nigerian Constitution with a view to ascertaining the extent of protection they afford environmental rights. It examines the provisions for environment protection in the constitution of some selected countries in order to engender a comparative insight. The paper makes a case for the entrenchment of environmental rights as enforceable rights under the Nigerian Constitution.Key words: Constitution, control, pollution, oil and ga