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The introduction of mobile telecommunication services in Nigeria led to the development of base transceiver stations (BTS) across the country. Inadequate power supply from the national grid has led to massive use of diesel-fueled back-up generators (BUGs). The purpose of this paper is to attempt to quantify and inform relevant stakeholders about air quality implications of BTS BUGs.

Seven major telecommunication network operators were identified. Emission factor approach was used to estimate the quantity of important air pollutants such as NO_x, CO, SO₂, PM₁₀, PM_2.5, PAH and TVOC that are emitted from the use of the BUGs based on fuel consumption rate and generators’ capacity. Fuel-based emission inventory and emission factor from the United States Environmental Protection Agency AP-42 and National Pollution Inventory were used to estimate pollutants emission from diesel-powered generators used in the BTS sites and amount of diesel consumed. Land distribution and per capita dose of the estimated pollutants load were calculated.

The study showed that the deployment of BUGs will lead to increase emissions of these air pollutants. The states that are most affected are Lagos, Kano and Oyo, Katsina and Akwa Ibom states with respective total air pollutants contribution of 9,539.61, 9,445.34, 8,276.46, 7,805.14 and 7,220.70 tonnes/yr.

This study has estimated pollutant emissions from the use of diesel-fueled BUGs in mobile telecommunications BTS sites in Nigeria. The data obtained could assist in policy making.

The purpose of this paper is to disseminate the lessons learned from the successful deployment of a wave energy converter (WEC) and accelerate growth in the field of ocean energy.

A thorough, well structured, documented, industrial approach was taken to the deployment because of the depth and scale of the task required. This approach is shown throughout the paper, which reflects the importance of a comprehensive project plan in success as well as failure.

The findings demonstrate the viability of the use of off shore WEC to generate electricity and that such a project can be completed on time and on budget.

The research implications of the paper include the importance of an enhanced, integrated supervisory system control in terms of efficiency, operation and maintenance, and long-term viability of WECs. This paper can be used to help guide the direction of further research in similar areas.

The practical implications include proof that WEC deployments can be carried out both on time and under budget. It highlights much of the practical data collected throughout the course of the project and presents it so that it might be used as a guide for future projects.

At the time of this paper, successful deployment of off shore WECs has been a rare accomplishment. Because the project was publicly funded, the data collected during this project, both technical and practical, is freely available.

The 11 September tragedy in the USA has provided a wake up call to remind businesses of the need for adequate disaster recovery and business continuity planning. A business continuity plan must be comprehensive and up to date. This paper outlines the key content of such a plan and the issues to be addressed in drawing one up to ensure it meets real business recovery needs. Continues the plan through to the actions needed to handle an actual emergency.

Storage systems are deemed to be unable to provide revenue commensurate with the resources invested in them, thus discouraging their incorporation within power networks. In prosumer microgrids, storage systems can provide revenue from reduced grid consumption, energy arbitraging or when serving as back-up power. This study aims to examine stacking these revenue streams with the aim of making storage systems financially viable for inclusion in prosumer microgrids.

With the aim of reducing self-consumption and maximising revenue, the prosumer microgrid incorporating hybrid energy storage systems (HESS) and solar PV power is solved using the CPLEX solver of the Advanced Interactive Multidimensional Modeling Software (AIMMS). The financial analysis of the results is carried out to provide the payback periods of different system configurations of the prosumer microgrid.

The findings reveal that the payback period of the three HESS when minimising grid expenses during self-consumption alone and when compared with stacked revenue streams shows an improvement from 4.8–11.2 years to 2.4–6.6 years. With stacked HESS revenues, the supercapacitor-lithium ion battery HESS gave the shortest payback period of 2.31 years when solar PV power is at 75% penetration level.

Existing literature has considered revenue streams of storage systems at the electrical power transmission and distribution levels, but not for prosumer microgrids in particular. This study has captured these benefits and verified the profitability of stacking revenue from HESS to prosumer microgrids, using a case study.

The purpose of this paper is to present a novel approach that examines the vulnerability and interdependency of critical infrastructures using the network theory in geographic information system (GIS) setting in combination with literature and government reports. Specifically, the objectives of this study were to generate the network models of critical infrastructure systems (CISs), particularly electricity, roads and sewerage networks; to characterize the CISs’ interdependencies; and to outline the climate adaptation (CA) and flood mitigation measures of CIS.

An integrated approach was undertaken in assessing the vulnerability and interdependency of critical infrastructures. A single system model and system-of-systems model were operationalized to examine the vulnerability and interdependency of the identified critical infrastructures in GIS environment. Existing CA and flood mitigation measures from government reports were integrated in the above-mentioned findings to better understand and gain focus in the implementation of natural disaster risk reduction (DRR) policies, particularly during the 2010/2011 floods in Queensland, Australia.

Using the results from the above-mentioned approach, the spatially explicit framework was developed with four key operational dimensions: conceiving the climate risk environment; understanding the critical infrastructures’ common cause and cascade failures; modeling individual infrastructure system and system-of-systems level within GIS setting; and integrating the above-mentioned results with the government reports to increase CA and resilience measures of flood-affected critical infrastructures.

While natural DRR measures include preparation, response and recovery, this study focused on flood mitigation. Temporal analysis and application to other natural disasters were also not considered in the analysis.

By providing this information, government-owned corporations, CISs managers and other concerned stakeholders will allow to identify infrastructure assets that are highly critical, identify vulnerable infrastructures within areas of very high flood risk, examine the interdependency of critical infrastructures and the effects of cascaded failures, identify ways of reducing flood risk and extreme climate events and prioritize DRR measures and CA strategies.

The individualist or “pigeon-hole” approach has been the common method of analyzing infrastructures’ exposure to flood hazards and tends to separately examine the risk for different types of infrastructure (e.g. electricity, water, sewerage, roads and rails and stormwater). This study introduced an integrated approach of analyzing infrastructure risk to damage and cascade failure due to flooding. Aside from introducing the integrated approach, this study operationalized GIS-based vulnerability assessment and interdependency of critical infrastructures which had been unsubstantially considered in the past analytical frameworks. The authors considered this study of high significance, considering that floodplain planning schemes often lack the consideration of critical infrastructure interdependency.

The emergence of “black swans” represents (according to Taleb) “[…] our misunderstanding of the likelihood of surprises”. The purpose of this paper is to study accidents and disasters and the inherent misunderstanding and absence of awareness associated with the existence of black swans and their complex aetiology. Red teaming and scenario planning provide a methodology to explore the uncertainties and challenge of the mental models associated with accident and disaster aetiology.

The argument draws upon the successful application of red teaming and scenario planning in various domains noted in the literature and lessons learned from the failure to recognize black swans. An analysis of the literature illustrates how the salient characteristics of red teaming and scenario planning can be applied to the illumination of black swans to support risk, crisis and disaster management.

Recognizing the uncertainty resident within the safety and security problem space opens up the notion that more than one future is potentially open. It is argued that the inherent properties of red teaming, within the context of scenario planning, facilitates an effective approach to bring risk, crisis and disaster planners/managers together to discuss their concerns and explore the factors creating uncertainty and the emergence of black swans.

The value of red teaming (scenario planning) to challenge linear thinking and recognize the inherent uncertainty in the space of possibilities is well supported. Applied to the risk, crisis and disaster management domain, red teaming and scenario planning can provide insights into the emergence of black swans and thereby shape mitigation strategies.

Nigeria, a prominent country in Sub-Sahara Africa, is plagued with a protracted, erratic and low power supply. The purpose of this paper is to present an experimental investigation of the noise levels and pollutants’ (CO, CO₂ and particulate matter (PM_2.5)) concentrations associated with the prevalent use of diesel-powered generators in the country. It is aimed to provide information on the level of gaseous, particulate and noise pollutants that are related to diesel-powered generators that could assist in policy formulation and create public awareness on the possible health risks.

Diesel-fueled generators (105) with age and installed capacity ranging from 0.5 to 14 years and 10 to 500 kVA, respectively, were engaged in this work at Sango area of Ogun State, Nigeria. Standard measuring instruments were placed at 1 m from the diesel-powered generators to determine the noise levels and concentrations of CO, CO₂ and PM_2.5.

Ranges of 72.6–115.6 dB, 19–198 ppm, 501–5,805 ppm and 221–492 µg/m³ for the noise level, CO, CO₂ and PM_2.5 concentrations, respectively, were obtained. Both the averages and ranges of the noise levels and pollutants’ concentrations were considerably higher than the recommended maximum limits. Thus, this study substantiated the pollution of ambient noise and air because of the operation of diesel-fueled generators. Furthermore, the health risks connected to the exposure to CO and PM_2.5 as implied via the evaluation of the air quality index revealed very unhealthy and hazardous conditions, respectively.

The measurement of the pollutants’ concentrations at the tips of the exhaust pipes of the diesel-powered generators was desirable but could not be achieved using manually logged devices. Nonetheless, adequate pollutants’ concentration data that satisfactorily represent the level of air pollution associated with diesel-fueled generators’ operations were obtained at around 1 m from the exhaust pipes.

The study provided additional knowledge on the levels of noise and pollutants, and the public health risks connected to the operations of diesel-powered generators that will be beneficial to the public and policymakers.

The results revealed a considerably high level of noise and air pollution, and the inherent environmental and public health problems connected to diesel-powered generators’ usage in Nigeria. This could serve as a viable tool for formulating environmental policy and providing the necessary societal awareness in this regard.

The aim of the present study is to overcome some of the limitations of the FMEA method by presenting a theoretical base for considering risk evaluation into its assessment methodology and proposing an approach for its implementation.

Fuzzy AHP is used to calculate the weights of the likelihood of occurrence (O), severity (S) and difficulty of detection (D). Additionally, the prospect-theory-based TODIM method was integrated with fuzzy logic. Thus, fuzzy TODIM was employed to calculate the ranking of potential failure modes according to their risk priority numbers (RPNs). In order to verify the results of the study, in-depth interviews were conducted with the participation of industry experts.

The results are very much in line with prospect theory. Therefore, practitioners may apply the proposed method to FMEA. The most crucial failure mode for a firm's attention is furnace failure followed by generator failure, crane failure, tank failure, kettle failure, dryer failure and operator failure, respectively.

The originality of this paper consists in integrating prospect theory with the FMEA method in order to overcome the limitations naturally inherent in the calculation of the FMEA's RPNs.

The purpose of this study is to propose the implementation of Lean Six Sigma (LSS) framework in supply chain by providing an actual case study of how to reduce the logistics cost.

In this paper, it is shown how LSS approach, basic tools and Define, Measure, Analyze, Improve and Control methodology can significantly improve a company by enhancing the supply chain and reducing the logistics expenditures.

Root causes to the main problem of this study were analyzed to identify appropriate solutions. After the implementation of solutions, the company’s product quality and internal communication were improved. Correspondingly, the percentage of customer orders that have to be transported by road instead of maritime reduced to 5% from 13% and the percentage of the road transportation cost paid unnecessarily by the company decreased to 1% from 5%.

This case study provides a roadmap and step-by-step implementation of LSS framework for especially companies in plastics industry.

To the best of the author’s knowledge, this paper is the first example of a LSS case study conducted in Turkey to improve the supply chain of a company by targeting primarily a reduction on logistics costs.

ROLLED out in May and scheduled to make its first flight in November is the V‐22 Osprey tiltrotor multi‐mission aircraft that has been ordered by four United States Services. Technological advances incorporated in the V‐22 had their beginnings in the XV‐3 in the mid 1950's which proved the feasibility of the tiltrotor concept and in the 1970's the XV‐15 programme explored and confirmed its validity. The latter aircraft which were jointly sponsored by NASA and the Army and Navy, have completed 600 hours of test flying and have demonstrated the suitability of this configuration for all kinds of military purposes.