Abdul Hameed, Syed Asif Raza, Qadeer Ahmed, Faisal Khan and Salim Ahmed
The purpose of this paper is to develop a decision support tool for risk-based maintenance scheduling for a large heavily equipped gas sweetening unit in a Liquefied Natural Gas…
Abstract
Purpose
The purpose of this paper is to develop a decision support tool for risk-based maintenance scheduling for a large heavily equipped gas sweetening unit in a Liquefied Natural Gas (LNG) plant. Two conflicting objectives, i.e., total maintenance cost and the reliability, are considered in the tool. The tool is tested with the real plant data and suggests several Pareto-optimal schedules for a decision maker to choose from. The financial impacts are assessed.
Design/methodology/approach
A bi-objective scheduling optimization model is developed for maintenance scheduling using a risk-based framework. The model is developed integrating genetic algorithm and simulation-based optimization to find Pareto-optimal schedules. The model delivered true Pareto front optimal solutions for given plant-specific data. The two conflicting objectives: the minimization of total expenditures incurred on maintenance-related activities and improving the total reliability are considered.
Findings
For large and complex processing facilities such as LNG plant, a shutdown of facility generates a significant financial impact, resulting in millions of dollars in production loss. The developed risk-based equipment selection strategy helps to minimize such an event of production loss by generating a thorough maintenance strategy for inspection, repair, overhaul or replacement schedule of the unit without initiating the shutdown. The proposed model has been successfully applied to obtain an optimize maintenance schedule for a gas sweetening unit.
Research limitations/implications
A future work may consider the state-dependent models for various failure modes that will result in obtaining a better representation of the model. The proposed scheduling can further be extended to multi-criteria scheduling including availability, resource limitation and inflationary condition. A comparative analysis with other meta-heuristic techniques such as harmony search algorithm, tabu search, and simulated annealing will further help in confirming the schedule obtained from this application.
Practical implications
Maintenance scheduling using a conventional approach for special equipment generally does not consider the conflicting objectives. This research addresses this aspect using a bi-objective model. The usefulness of risk-based method is to assist in minimizing the financial and safety risk exposure to the operating companies, but some variation in results is expected due to varying risk matrix for different organizations.
Social implications
Managing two objectives, i.e., minimizing the cost of maintenance-related activities, while at the same time maximizing the overall reliability dramatically, helps in mitigating adverse safety and financial risk due to fires, explosions, fatality and excessive maintenance cost.
Originality/value
Research develops a decision support tool for managing conflicting objectives for an LNG process. This research highlights the impact of utilizing the simulation-based approach coupled with risk-based equipment selection for complex processing unit or plant maintenance scheduling optimization.
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Kambiz Mokhtari, Noorul Shaiful Fitri Abdul Rahman, Hamid Reza Soltani, Salim Ahmed Al Rashdi and Kawkab Abdul Aziz Mohammed Al Balushi
At the substantive level, there exists a gap in knowledge about the position of security risk management (i.e. SRM) during the terminals’ operations and management; particularly…
Abstract
Purpose
At the substantive level, there exists a gap in knowledge about the position of security risk management (i.e. SRM) during the terminals’ operations and management; particularly when there is potential for deliberate anti-security acts. Correspondingly, the purpose of this paper is a need for more practical research to find out the justification for the existence of the SRM and different techniques for its appropriate execution on these logistics infrastructures principally with due regard to the potential requirements in the near future.
Design/methodology/approach
Both qualitative and quantitative techniques are used in this study incorporating fuzzy set theory and risk assessment matrix to achieve the research objective.
Findings
A designed SRM framework tailored for Qalhat liquefied petroleum gas (LNG) terminal in Sultanate of Oman was established to manage the security threats which can be resulted from any probable terrorist attacks.
Research limitations/implications
The limited numbers of experts for the purpose of the addressed SRM are causing challenges in data collection.
Practical implications
The pressures for enhanced attention to critical infrastructure security have fostered new challenges for petrochemical seaports and terminals (PSTs). These tendencies dictate to maintain comprehensive security regimens that can be integrated with national and international strategies to support the country’s security against terrorism.
Originality/value
The development of the security risk factor table model in the case of Qalhat LNG Terminal.
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Salim Ahmed, Khushboo Kumari and Durgeshwer Singh
Petroleum hydrocarbons are naturally occurring flammable fossil fuels used as conventional energy sources. It has carcinogenic, mutagenic properties and is considered a hazardous…
Abstract
Purpose
Petroleum hydrocarbons are naturally occurring flammable fossil fuels used as conventional energy sources. It has carcinogenic, mutagenic properties and is considered a hazardous pollutant. Soil contaminated with petroleum hydrocarbons adversely affects the properties of soil. This paper aim to remove pollutants from the environment is an urgent need of the hour to maintain the proper functioning of soil ecosystems.
Design/methodology/approach
The ability of micro-organisms to degrade petroleum hydrocarbons makes it possible to use these microorganisms to clean the environment from petroleum pollution. For preparing this review, research papers and review articles related to petroleum hydrocarbons degradation by micro-organisms were collected from journals and various search engines.
Findings
Various physical and chemical methods are used for remediation of petroleum hydrocarbons contaminants. However, these methods have several disadvantages. This paper will discuss a novel understanding of petroleum hydrocarbons degradation and how micro-organisms help in petroleum-contaminated soil restoration. Bioremediation is recognized as the most environment-friendly technique for remediation. The research studies demonstrated that bacterial consortium have high biodegradation rate of petroleum hydrocarbons ranging from 83% to 89%.
Social implications
Proper management of petroleum hydrocarbons pollutants from the environment is necessary because of their toxicity effects on human and environmental health.
Originality/value
This paper discussed novel mechanisms adopted by bacteria for biodegradation of petroleum hydrocarbons, aerobic and anaerobic biodegradation pathways, genes and enzymes involved in petroleum hydrocarbons biodegradation.
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These moves are the latest manifestation of Samia’s efforts to reshape the domestic political space and deliver on her agenda ahead of the 2025 presidential election.
Details
DOI: 10.1108/OXAN-DB282212
ISSN: 2633-304X
Keywords
Geographic
Topical
Currently, more than 300,000 children under the age of eighteen are fighting as soldiers with government armed forces and armed opposition groups in more than thirty countries…
Abstract
Currently, more than 300,000 children under the age of eighteen are fighting as soldiers with government armed forces and armed opposition groups in more than thirty countries worldwide. In more than eighty-five countries, hundreds of thousands more under-eighteens have been recruited into government armed forces, paramilitaries, civil militia and a wide variety of non-state armed groups. Millions of children worldwide receive military training and indoctrination in youth movements and schools. While most child soldiers are aged between fifteen and eighteen, the youngest age reported is seven (UN Chronicle, Winter 2000).
This research attempts to identify and observe emerging features of public administration (PA) in Mozambique, Africaʼs newest democracy. Mozambiqueʼs public administration has had…
Abstract
This research attempts to identify and observe emerging features of public administration (PA) in Mozambique, Africaʼs newest democracy. Mozambiqueʼs public administration has had to assume a significant role in the process of promoting sustainable human development. Public administration in the country is challenged by Napoleonic character of Constitutional arrangements for administering public policy, shortage of skilled human capital and the apparent absence of human development plans that would facilitate a more engaged civil society.
Benjamin Jones and Daniel Campbell
Winner of the 2014 EFMD competition for best African Business case.In the 1990s, two entrepreneurs made daring, early entries into mobile telecommunications in Sub-Saharan Africa…
Abstract
Winner of the 2014 EFMD competition for best African Business case.
In the 1990s, two entrepreneurs made daring, early entries into mobile telecommunications in Sub-Saharan Africa, both seeing great market opportunities there. One firm, Adesemi, would ultimately go bankrupt. The other firm, Celtel, would ultimately succeed and make its founder, Mo Ibrahim, a star of the global business community. Why the difference in outcome? Emerging markets often present weak rule of law, bringing many challenges to business success—from the demand for bribes to regulatory obstacles, hold-up problems, and even civil war. This case explores strategies that can limit these critical non-market risks in foreign direct investment and entrepreneurship. Students will step into the shoes of both companies by exploring their entry strategies, wrestling with the challenges they faced, and diagnosing the reasons why a shared insight about a new business opportunity turned out to be prescient—and led to extremely different endpoints.
Identify key challenges to successful entrepreneurship in emerging markets
Evaluate government officials or competitors that might trigger regulatory obstacles or hold-up problems
Evaluate potential allies that can help avoid these problems
Assess strategies to avoid paying bribes
Understand the importance of incentive alignment in directing investment success, even in the face of difficult challenges
Identify and appraise the strategic value of partnerships with development agencie
Identify key challenges to successful entrepreneurship in emerging markets
Evaluate government officials or competitors that might trigger regulatory obstacles or hold-up problems
Evaluate potential allies that can help avoid these problems
Assess strategies to avoid paying bribes
Understand the importance of incentive alignment in directing investment success, even in the face of difficult challenges
Identify and appraise the strategic value of partnerships with development agencie
Details
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Keywords
Sudan's state of emergency.
Details
DOI: 10.1108/OXAN-DB242263
ISSN: 2633-304X
Keywords
Geographic
Topical
Ammar Ahmed, Muhammad Aqeel and Naeem Aslam Chughtai
The purpose of this paper is to focus on the indigenous need for public health challenges being faced by the patients in Pakistan because of vertigo symptoms. Vertigo or benign…
Abstract
Purpose
The purpose of this paper is to focus on the indigenous need for public health challenges being faced by the patients in Pakistan because of vertigo symptoms. Vertigo or benign paroxysmal positional vertigo is described as short episodes of dizziness (spinning sensations) that are caused because of movements of head in varying directions. Various published accounts have linked vertigo to psychological and psychiatric symptoms, which include stress, anxiety and depression. The aim of present study is to examine the validity and reliability of Dizziness Handicap Inventory (DHI) Urdu version that is vital in the diagnosis, evaluation and treatment of patients coming in hospitals.
Design/methodology/approach
This present study included two segments, namely, preliminary and main study. Preliminary study results indicated that the overall scale had high internal consistency of DHI Urdu version α = 0.95. The overall scale retained a high test-retest correlation tested over a period of 15 days (r = 0.93). Main study was performed on 222 vestibulocochlear disorder patients having chief complaints of tinnitus and vertigo, age ranged from 18 to 89 (M = 46.14; SD = 16.64) and recruited from various hospitals of Islamabad and Rawalpindi, Pakistan. Purposive sampling technique was applied based on cross-sectional design.
Findings
Significant correlations were noted between dizziness symptoms rating on the translated scale. Confirmatory factor analysis was used to determine the structure of the scales; an orthogonal rotation (Varimax) was conducted on the data collected from patients. A three-factor solution was obtained for DHI, the factors obtained were associated to the subscales vestibular handicap, vestibular disability and visuo-vestibular disability, demonstrating a strong factorial validity in the Pakistani cultural context.
Originality/value
Vertigo is a symptom that initiates various psychological issues among vestibulocochlear disorder patients (patients having ear related problems) around the world and therefore the investigated inventory offers an initial assessment for the severity of dizziness. Current research will help in the development of indigenous measures to ascertain the severity of the symptoms triggering various other mental health-related issues.
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Stig Stenslie and Kjetil Selvik
The chapter compares the survival of old regime elites in Tunisia and Egypt after the 2011 uprisings and analyses its enabling factors. Although democracy progressed in Tunisia…
Abstract
The chapter compares the survival of old regime elites in Tunisia and Egypt after the 2011 uprisings and analyses its enabling factors. Although democracy progressed in Tunisia and collapsed in Egypt, the countries show similarities in the old elite’s ability to survive the Arab Spring. In both cases, the popular uprisings resulted in the type of elite circulation that John Higley and György Lengyel refer to as ‘quasi-replacement circulation’, which is sudden and coerced, but narrow and shallow. To account for this converging outcome, the chapter foregrounds the instability, economic decline and information uncertainty in the countries post-uprising and the navigating resources, which the old elites possessed. The roots of the quasi-replacement circulation are traced to the old elites’ privileged access to money, network, the media and, for Egypt, external support. Only parts of the structures of authority in a political regime are formal. The findings show the importance of evaluating regime change in a broader view than the formal institutional set-up. In Tunisia and Egypt, the informal structures of the anciens régimes survived – so did the old regime elites.