Search results
1 – 10 of over 9000Yingsai Cao, Sifeng Liu and Zhigeng Fang
The purpose of this paper is to propose new importance measures for degrading components based on Shapley value, which can provide answers about how important players are to the…
Abstract
Purpose
The purpose of this paper is to propose new importance measures for degrading components based on Shapley value, which can provide answers about how important players are to the whole cooperative game and what payoff each player can reasonably expect.
Design/methodology/approach
The proposed importance measure characterizes how a specific degrading component contributes to the degradation of system reliability by using Shapley value. Degradation models are also introduced to assess the reliability of degrading components. The reliability of system consisting independent degrading components is obtained by using structure functions, while reliability of system comprising correlated degrading components is evaluated with a multivariate distribution.
Findings
The ranking of degrading components according to the newly developed importance measure depends on the degradation parameters of components, system structure and parameters characterizing the association of components.
Originality/value
Considering the fact that reliability degradation of engineering systems and equipment are often attributed to the degradation of a particular or set of components that are characterized by degrading features. This paper proposes new importance measures for degrading components based on Shapley value to reflect the responsibility of each degrading component for the deterioration of system reliability. The results are also able to give timely feedback of the expected contribution of each degrading component to system reliability degradation.
Details
Keywords
This paper explores the health rights of prisoners as defined in international law, and the mechanisms that have been used to ensure the rights of persons in detention to realise…
Abstract
This paper explores the health rights of prisoners as defined in international law, and the mechanisms that have been used to ensure the rights of persons in detention to realise the highest attainable standard of health. It examines this right as articulated within United Nations and regional human rights treaties, non‐binding or so‐called soft law instruments from international organisations and the jurisprudence of international human rights bodies. It explores the use of economic, social and cultural rights mechanisms, and those within civil and political rights, as they engage the right to health of prisoners, and identifies the minimum legal obligations of governments in order to remain compliant with human rights norms as defined within the international case law. In addressing these issues, this article adopts a holistic approach to the definition of the highest attainable standard of health. This includes a consideration of adequate standards of general medical care, including preventative health and mental health services. It also examines the question of environmental health, and those poor conditions of detention that may exacerbate health decline, disease transmission, mental illness or death. The paper examines the approach to prison health of the United Nations human rights system and its various monitoring bodies, as well as the regional human rights systems in Europe, Africa and the Americas. Based upon this analysis, the paper draws conclusions on the current fulfilment of the right to health of prisoners on an international scale, and proposes expanded mechanisms under the UN Convention against Torture and Other Cruel, Inhuman or Degrading Treatment to monitor and promote the health rights of prisoners at the international and domestic levels.
Details
Keywords
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.
Details
Keywords
The study aimed at developing the bioremediation model of Lapindo mud through multisymbiotic organism.
Abstract
Purpose
The study aimed at developing the bioremediation model of Lapindo mud through multisymbiotic organism.
Design/methodology/approach
The research was conducted using completely randomized design. The model plants chosen in this research were soybean. The interaction pattern during the treatment was used to develop the bioremediation model based on the parameters.
Findings
The results showed that there was an effect of the type of organism on the parameters, namely: the growth of plant (biomass, height, length of root, and number of leaves), the biomass of root nodules, the percentage of mycorrhizal infection, the content of water, nitrogen, phosphorus, and total petroleum hydrocarbons (TPHs). There was a pattern of multisymbiotic interaction between each organism and roles of each symbiont in that interaction. Therefore, the plants were capable of surviving in the environment of Sidoarjo Lapindo mud. This pattern can be named as the bioremediation model proposed, which is the analogy of tripartite symbiosis between plants, mycorrhizae, and Rhizobium but also adding plant growth bacteria such as phosphate-solubilizing bacteria and hydrocarbon degradation bacteria. The implementation of this model can be used to treat oil-contaminated soil in order to be used as a plant growth medium.
Originality/value
Phytoremediation is a new and promising approach to remove contaminants in the environment but using plants alone for remediation confronts many limitations. Therefore, the application of plant-growth-promoting rhizobia (PGPR) has been extended to remediate contaminated soils in association with plants (Zhuang et al., 2007). The development of the model will use the analogy of tripartite symbiosis between plants, mycorrhizae, and Rhizobium. The developed model will be based on the interaction pattern on each parameters obtained. Bioremediation is chosen because it is considered an effective technique to transform toxic components into less toxic products without disrupting the surrounding environment. Besides, bioremediation is cheaper and environment-friendly because it utilizes microorganisms to clean pollutants from the environment (Nugroho, 2006).
Details
Keywords
Mats Neovius, Fredrik Degerlund and Lu Yan
Trust in open networks has emerged as a prime research topic, partly due to the vast unexploited possibilities unrestricted distribution of ideas, innovations and information…
Abstract
Purpose
Trust in open networks has emerged as a prime research topic, partly due to the vast unexploited possibilities unrestricted distribution of ideas, innovations and information provided. This paper aims to present an abstract model for anticipating the probabilities of the target object to meet with the expectations of the inquirer, emphasising consistent behaviour and managing diverse conceptions by relying on sentimentally like‐minded.
Design/methodology/approach
The basic building blocks of trust are presented and motivated. Each presented problem is addressed and formulas facilitating rightful interpretation are given.
Findings
The paper presents some ideas how to approach the problems faced when rightfully interpreting information gathered from anonymous collaborates in a scalable manner by pointing out the basics of them.
Research limitations/implications
This paper depicts ideas as illustrations that are easy to understand and give an overview of the fundamentals on which to conduct further research.
Originality/value
The paper provides a conceptual discussion of the need for trust in open networks.
Details
Keywords
SUDIP S. BHATTACHARJEE and PIERRE LÉGER
The localized strain softening behaviour of concrete has been modelled by two approaches: (i) the stiffness degrading model based on the total stress‐strain constitutive…
Abstract
The localized strain softening behaviour of concrete has been modelled by two approaches: (i) the stiffness degrading model based on the total stress‐strain constitutive relationship, and (ii) the tangent softening model based on the incremental stress‐strain relationship. The models are implemented using a new softening initiation criterion proposed for application in multi‐dimensional finite element analysis. Parametric analyses on plain concrete beams, tested experimentally by other researchers, have been carried out to investigate the required numerical efforts, the mesh objectivity, and the energy dissipation characteristics of the structures. The stiffness degrading model is very stable even when applied with relatively coarse finite element meshes. However, the computational demand of this model is relatively high. The combination of a total stress‐strain constitutive relationship to compute the element responses, and an incremental relationship to formulate the stiffness matrix, appears to be computationally efficient and stable, provided that adequately refined finite element mesh is used to model the structure.
Details
Keywords
Ongo Nkoa Bruno Emmanuel, Dobdinga Cletus Fonchamnyo, Mamadou Asngar Thierry and Gildas Dohba Dinga
The continuous increase in the negative gap between biocapacity and ecological footprint has remained globally persistent since early 1970. The purpose of this study is to examine…
Abstract
Purpose
The continuous increase in the negative gap between biocapacity and ecological footprint has remained globally persistent since early 1970. The purpose of this study is to examine the effect of foreign capital, domestic capital formation, institutional quality and democracy on ecological footprint within a global panel of 101 countries from 1995 to 2017.
Design/methodology/approach
The empirical procedure is based on data mix. To this end, this study uses a battery of testing and estimation approaches both conventional (no cross-sectional dependence [CD]) and novel approaches (accounting for CD). Among the battery of estimation techniques used, there are the dynamic ordinary least square, the mean group, the common correlation effect mean group technique, the augmented mean group technique, the Pooled mean group and the dynamic common correlation effect technique with the desire to obtain outcomes robust to heteroskedasticity, endogeneity, cross-correlation and CD among others.
Findings
The estimated outcomes indicate that using different estimators’ domestic capital formation consistently degrades the environment through an increase in ecological footprint, while institutional quality consistently enhances the quality of the environment. Further, the outcome reveals that, though foreign capital inflow degrades the environment, the time period is essential, as it shows a short-run environmental improvement and a long-run environmental degradation. Democratic activities show a mixed outcome with short-run degrading effect and a long-run enhancement effect on environmental quality.
Practical implications
Green investment should be the policy target of all economies, and these policies should be adopted to target both domestic capital and foreign capital alike. Second, the adoption of democratic practices will produce good leaders that will not just design short-term policies to blindfold the populace temporary but those that will produce long-term-oriented practices that will better and enhance the quality of the environment through the reduction of the global footprint. Equally, enhancing the institutional framework like respect for the rule of law in matters of abatement should be encouraged.
Originality/value
Although much research on the role of macroeconomic indicators on environmental quality has been done this far, democratic practices, intuitional quality and domestic capital have been given little attention. This research fills this gap by considering robust empirical techniques.
Details
Keywords
Jakiul Hassan, Premkumar Thodi and Faisal Khan
– The purpose of this paper is to propose a state dependent stochastic Markov model for availability analysis of process plant instead of traditional time dependent model.
Abstract
Purpose
The purpose of this paper is to propose a state dependent stochastic Markov model for availability analysis of process plant instead of traditional time dependent model.
Design/methodology/approach
The traditional concepts of system performance measurement and reliability (namely, binary; two-state concepts) are observed to be inadequate to characterize performance of complex system components. Availability analysis considering an intermediate state, such as a degraded state, provides a better alternative mechanism for system performance mapping. The availability model provides a better assessment of failure and repair characteristics for equipment in the sub-system and its overall performance. In addition to availability analysis, this paper also discusses the preventive maintenance (PM) program to achieve target availability. In this model, the degraded state is considered as a PM state. Using Markov analysis the optimum maintenance interval is determined.
Findings
Markov process provides an easier way to measure the performance of the process facility. This study also revealed that the maintenance interval has a major influence in the availability of a process facility as well as in maintaining target availability. The developed model is also applicable to the varying target availability as well as having the capability to handle even the reconfigured process systems.
Research limitations/implications
Considering the degraded state as an operative state, a higher availability of the plant is predicted. The consideration of the degraded state of the system makes the availability estimation more realistic and acceptable. Availability quantification, target availability allocation and a PM model are exemplified in a sub-system of an liquefied natural gas facility.
Originality/value
The unique features of the present study are; Markov modeling approach integrating availability and PM; optimum PM interval determination of stochastically degrading components based on target availability; consideration of three-state systems; and consideration of increasing failure rates.
Details
Keywords
Radhia Chabbi, Noureddine Ferhoune and Fouzia Bouabdallah
This research aims to study the materials that compose older reinforced concrete bridges which are damaged and degrading to explain the mechanisms and origins of various…
Abstract
Purpose
This research aims to study the materials that compose older reinforced concrete bridges which are damaged and degrading to explain the mechanisms and origins of various disorders. Therefore, this work will contribute to providing answers on the capacity of nondestructive evaluation method during the diagnosis. In addition to the characterization of affected structures, it will aim to provide effective solutions for different serious pathologies.
Design/methodology/approach
In this context, two bridges located on NH16 and NH21, respectively, were studied in Annaba city (north-east Algeria), specifically in El-Hadjar municipality located in the central industrial zone of Pont-Bouchet. This study makes it possible to make conclusions from the in-depth diagnosis based on disorders exposition causes and mechanical characteristics evolution by non-destructive testing (NDT) tools. Furthermore, solutions are proposed, including conservation maintenance of these degraded structures.
Findings
All degradations can be the result of several factors: either human (poor design) or chemical (surface water, wastewater and groundwater quality (acidic or basic)). In addition to other natural causes (geological formations, flood phenomena or climate), NDT tools play a major role in the evaluating mechanical performance of degraded structures (resistance and hardness).
Research limitations/implications
The NDT techniques can be transmitted to civil engineering experts because their training is limited regarding mechanical and structural construction.
Practical implications
NDT tools are the most suitable for in-situ assessing, and the concrete constructions health state, so far from financial problems.
Social implications
Degraded bridge diagnosis by NDT testing is necessary for a thorough safety evaluation (mechanical performance, strength and deformability), to protect human lives and design durability.
Originality/value
This is an original paper which contains new information at different scales and from special fields, based on an evaluation using NDT tools on real degraded structures. It can be used to improve the knowledge of materials employed in a bridge without performing expensive direct tests or the need for destroying it.
Details
Keywords
Health care practitioners in prison face the challenge of providing high standards of health care within the unique peculiarities and restraints of the prison environment. The…
Abstract
Health care practitioners in prison face the challenge of providing high standards of health care within the unique peculiarities and restraints of the prison environment. The strict adherence to principles of medical ethics by the prison health care staff and the knowledge and acceptance of these principles by the whole prison community not only results in ethical conduct but also yields practical professional advantages such as guidance in situations of conflict, promotion of confidence and avoidance of misunderstandings. The internationally consented conventions, declarations and recommendations relevant on medical ethics in prison are presented and their basic principles ‐ the primary task of the prison doctor, access to a doctor, equivalence of care, patient’s consent and confidentiality, preventive health care, humanitarian assistance, professional independence, professional competence ‐ are discussed. In addition, the personal obligation of the prison doctor for ethical reflection and decision making in individual ethical issues not covered by the quoted documents and in ethically controversial issues is emphasized. A training course and published guidelines for ethical conduct in prison health care are recommended.
Details