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1 – 10 of 27
Article
Publication date: 24 September 2019

Sahar Feili, H.R. Sabouhi, Hassan Sobhani and M. Traz

This study aims to propose a new scheme for designing a high-sensitivity optical biosensor. For this, two agents have been considered: reflection-type micro-resonators…

Abstract

Purpose

This study aims to propose a new scheme for designing a high-sensitivity optical biosensor. For this, two agents have been considered: reflection-type micro-resonators, which filter the noise of the pump, and coupled-ring reflectors (CRRs), which are coupled to partial reflecting elements in the bus waveguide to create Fano-resonance. These two agents improve the sensor sensitivity and have low-power optical switching/modulation.

Design/methodology/approach

The proposed model is based on the coupling of the CRRs with the Fabry–Pérot cavity. The slope of the Fano-resonance line shape and consequently the sensitivity of the proposed CRRs are higher than those of conventional microring resonators.

Findings

The proposed scheme has many characteristics: CRRs have been used to create a higher slope of the Fano-resonance line shape; the sensitivity of the sensor shows improvement on the basis of reflection-type micro-resonators and by the removal of the pump noise; the designed sensor has low-power optical switching/modulation; and the modeling and designing of a novel high-sensitivity resonator is based on coupling the CRRs with the Fabry–Pérot cavity.

Originality/value

This study has proposed a new scheme for designing a high-sensitivity optical biosensor. This method is based on the improvement of the sensitivity by two agents: reflection-type micro-resonators, which filter the noise of the pump, and coupled-ring reflectors, which are coupled to partial reflecting elements in the bus waveguide to create Fano-resonance.

Details

Sensor Review, vol. 39 no. 6
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 4 December 2020

Fatemeh Sabouhi, Ali Bozorgi-Amiri and Parinaz Vaez

This study aims to minimize the expected arrival time of relief vehicles to the affected areas, considering the destruction of potential routes and disruptions due to…

Abstract

Purpose

This study aims to minimize the expected arrival time of relief vehicles to the affected areas, considering the destruction of potential routes and disruptions due to disasters. In relief operations, required relief items in each affected area and disrupted routes are considered as uncertain parameters. Additionally, for a more realistic consideration of the situations, it is assumed that the demand of each affected area could be met by multiple vehicles and distribution centers (DCs) and vehicles have limited capacity.

Design/methodology/approach

The current study developed a two-stage stochastic programming model for the distribution of relief items from DCs to the affected areas. Locating the DCs was the first-stage decisions in the introduced model. The second-stage decisions consisted of routing and scheduling of the vehicles to reach the affected areas.

Findings

In this paper, 7th district of Tehran was selected as a case study to assess the applicability of the model, and related results and different sensitivity analyses were presented as well. By carrying out a simultaneous sensitivity analysis on the capacity of vehicles and the maximum number of DCs that can be opened, optimal values for these parameters were determined, that would help making optimal decisions upon the occurrence of a disaster to decrease total relief time and to maximize the exploitation of available facilities.

Originality/value

The contributions of this paper are as below: presenting an integrated model for the distribution of relief items among affected areas in the response phase of a disaster, using a two-stage stochastic programming approach to cope with route disruptions and uncertain demands for relief items, determining location of the DCs and routing and scheduling of vehicles to relief operations and considering a heterogeneous fleet of capacitated relief vehicles and DCs with limited capacity and fulfilling the demand of each affected area by more than one vehicle to represent more realistic situations.

Details

Kybernetes, vol. 50 no. 9
Type: Research Article
ISSN: 0368-492X

Keywords

Book part
Publication date: 16 July 2019

Mathew Donald

Abstract

Details

Leading and Managing Change in the Age of Disruption and Artificial Intelligence
Type: Book
ISBN: 978-1-78756-368-1

Article
Publication date: 3 November 2020

Hamed Sabouhi, Aref Doroudi, Mahmud Fotuhi-Firuzabad and Mahdi Bashiri

This paper aims to propose a novel matrix-based systematic approach for vulnerability assessment.

Abstract

Purpose

This paper aims to propose a novel matrix-based systematic approach for vulnerability assessment.

Design/methodology/approach

The proposed method consists of two major steps. First, the power network is modeled as a topological combination of edges (transmission lines, transformers, etc.) and nodes (buses, substations, etc.). The second step is to use an axiomatic design-based index for topology analysis. This index is based on the systematic counting of possible routes from the start (generators) to destination (loads), considering load importance, before and after a disruption.

Findings

The effectiveness of the proposed method is demonstrated through an illustrative example and the Institute of Electrical and Electronics Engineers (IEEE) 14-bus power system. It was shown that the load’s importance influences the results of the vulnerability analysis. The proposed method has some advantages over traditional graph theory such as an explicit description of multiple transmission nodes and assets with multiple conversion processes. Furthermore, it would help the power grid operators and asset investment managers to be better to assess the vulnerable components.

Research limitations/implications

The proposed method can be used in planning, optimization, robustness and hardening of power systems.

Originality/value

The paper presents a matrix-based systematic approach to evaluate and quantify the vulnerability of the power grid’s components.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 40 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 12 July 2021

Obaid ur Rehman and Yousaf Ali

Resilience is a fundamental component of healthcare supply chains, as the quality and endurance of human life are dependent on them. However, there are numerous…

Abstract

Purpose

Resilience is a fundamental component of healthcare supply chains, as the quality and endurance of human life are dependent on them. However, there are numerous resilience-building measures, and there is a need for prioritization of those strategies. This research study aims to prioritize resilience strategies for healthcare supply chains while considering the risks that most severe, probable to occur and have the lengthiest periods of recovery.

Design/methodology/approach

This research study has used multi-criteria decision-making (MCDM) techniques for analysis. Initially, the criteria for prioritization of risks, i.e. severity, probability of occurrence and recovery time were assigned with importance weights through the fuzzy analytical hierarchy process (AHP). Then, these weights were used in the fuzzy technique for order preference by similarity to ideal solution (TOPIS) analysis for prioritization of risks. Subsequently, the identified risks were used for highlighting the appropriate resilience strategies through the fuzzy quality function deployment (QFD) technique.

Findings

Results indicate that Industry 4.0, multiple sourcing, risk awareness, agility and global diversification of suppliers, markets and operations are the most significant resilience strategies.

Research limitations/implications

This study's limitation is that it is conducted in a general perspective, rather than reducing the context to a developing or developed country. Different areas have variable market factors, due to which potential risks occur in a different form. Moreover, resilience strategies work differently in different environments. Therefore, for future endeavors, the studies should be carried out in a limited context.

Originality/value

This research study proposes a novel MCDM-based approach for ranking resilience strategies, in light of the most probable, severe and long-lasting risks. In addition, this approach has been employed for the enhancement of resilience in healthcare supply chains.

Details

The International Journal of Logistics Management, vol. 33 no. 2
Type: Research Article
ISSN: 0957-4093

Keywords

Article
Publication date: 9 October 2019

Mohsen Babaei, Afshin Shariat-Mohaymany, Nariman Nikoo and Ahmad-Reza Ghaffari

One of the problems in post-earthquake disaster management in developing countries, such as Iran, is the prediction of the residual network available for disaster relief…

Abstract

Purpose

One of the problems in post-earthquake disaster management in developing countries, such as Iran, is the prediction of the residual network available for disaster relief operations. Therefore, it is important to use methods that are executable in such countries given the limited amount of accurate data. The purpose of this paper is to present a multi-objective model that seeks to determine the set of roads of a transportation network that should preserve its role in carrying out disaster relief operations (i.e. known as “emergency road network” (ERN)) in the aftermath of earthquakes.

Design/methodology/approach

In this paper, the total travel time of emergency trips, the total length of network and the provision of coverage to the emergency demand/supply points have been incorporated as three important metrics of ERN into a multi-objective mixed integer linear programming model. The proposed model has been solved by adopting the e-constraint method.

Findings

The results of applying the model to Tehran’s highway network indicated that the least possible length for the emergency transportation network is about half the total length of its major roads (freeways and major arterials).

Practical implications

Gathering detailed data about origin-destination pair of emergency trips and network characteristics have a direct effect on designing a suitable emergency network in pre-disaster phase.

Originality/value

To become solvable in a reasonable time, especially in large-scale cases, the problem has been modeled based on a decomposing technique. The model has been solved successfully for the emergency roads of Tehran within about 10 min of CPU time.

Details

Journal of Humanitarian Logistics and Supply Chain Management, vol. 9 no. 2
Type: Research Article
ISSN: 2042-6747

Keywords

Open Access
Article
Publication date: 27 July 2020

Girish Chandra, Avinash Jain and Sanjay Kumar

The estimation of market value of intangible benefits of afforestation has always been a challenging task, and the contingent valuation method is a popular method used in…

Abstract

Purpose

The estimation of market value of intangible benefits of afforestation has always been a challenging task, and the contingent valuation method is a popular method used in environmental assessment. The NTPC set up a coal-based power plant in Korba, India and planted 1.6 million trees on 19% of the project area.

Design/methodology/approach

The individual's mean and median willingness to pay (WTP) for four intangible benefits, namely, pollution control (PC), improvement in underground water level (IUGWL), soil conservation and remediation (SCR) in addition to total WTP from the afforestation program of NTPC were estimated using a customized procedure for logit model based upon respondent's age, education, occupation, income and bid amount asked to pay. Stratified multistage random sampling has been used to select the respondents.

Findings

The procedure increases the number of respondents who are willing to pay as compared to conventional CVM. The finding of the study shows that the highest WTP was observed for PC (Rs. 462.84 per month per household) followed by SCR and IUGWL, whereas for total WTP it was Rs. 972.60.

Originality/value

The proposed customized procedure and the results thereof would be useful in improving the WTP estimates for other similar studies in order to conserve the environment.

Details

Forestry Economics Review, vol. 2 no. 1
Type: Research Article
ISSN: 2631-3030

Keywords

Article
Publication date: 6 February 2019

Sorabh Gupta

The purpose of this paper is to present the technique for evaluating the performance of a condensate system of a coal-based thermal power plant situated in the northern…

Abstract

Purpose

The purpose of this paper is to present the technique for evaluating the performance of a condensate system of a coal-based thermal power plant situated in the northern part of India. The data which used for system availability evaluation are not precise and are uncertain and, further, collected from concerned power plant history sheets and from discussion through plant personnel.

Design/methodology/approach

In the proposed model, traditional Markov birth-death process using a probabilistic approach is used to analyze the performance of a complex repairable condensate system of power plant up to a desired degree of accuracy. This approach has been demonstrated by breaking the condensate system into six subsystems arranged in series with two feasible states, namely, working and failed, labeled in a transition diagram and modeled as a Markov process, using Chapman–Kolmogorov equations, which are used for development of a probabilistic stochastic model for availability analysis in a more effecting manner, considering some suitable assumptions.

Findings

This study of analysis of reliability and availability can help in increasing the plant production and performance. The analysis is done with the help of availability matrices, which are developed using different combinations of failures and repair rates of all subsystems. To achieve the goal of maximum power generation, it is required to run the various subsystem of the concerned system of plant, failure free for a long duration. Therefore, the present approach may be a more powerful analysis tool to access the performance of all subsystems of a condensate system in terms of availability level achieved in availability matrices. The results of present study are found to be highly beneficial to the plant management for making maintenance decisions.

Originality/value

The present paper suggests a suitable technique for stochastic modeling and availability evaluation of an industrial system using Markovian approach and drawing a transition diagram to represent the operational behavior of the system. The present methodology includes the advantage of the ability to model and develop a more complex industrial system and helps in improving the performance and handling the uncertainties and possibilities of an industrial system.

Details

International Journal of Quality & Reliability Management, vol. 36 no. 5
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 13 August 2021

Mosayeb Dashtpeyma and Reza Ghodsi

This research paper aims to identify and evaluate the enabling factors of agility capability in humanitarian relief chain network.

Abstract

Purpose

This research paper aims to identify and evaluate the enabling factors of agility capability in humanitarian relief chain network.

Design/methodology/approach

The research phases were implemented based on an integrated framework. First, a reference framework of the enablers has been constructed based on a literature review. Then, a hybrid evaluation approach is applied that combines fuzzy decision-making trial and evaluation laboratory (DEMATEL) and analytic network process (ANP) to achieve reliable results. It provides a road map to identify and evaluate the interactions between the enabling factors and determines the weights correspond to their relative importance. This approach takes advantage of fuzzy set theory to deal with ambiguities, uncertainties and vagueness inherent in the evaluation process.

Findings

Relief chain agility is a vital determinant of the effectiveness to succeed humanitarian missions during and after natural and unnatural disasters such as earthquakes, epidemics and terrorist attacks. Results shed light on the essential enabling factors, relationships among them, and their importance for developing humanitarian relief chain agility enhancing the overall performance quality.

Originality/value

The integrated framework is implemented for the Red Crescent, a nongovernmental organization in Iran, which is trying to optimize the agility of their humanitarian relief chain network. In short, the findings are beneficial for identification and utilization of the essential prerequisites of agility in order to develop an agile humanitarian relief chain.

Details

International Journal of Emergency Services, vol. 11 no. 1
Type: Research Article
ISSN: 2047-0894

Keywords

Article
Publication date: 27 December 2021

Sara Nodoust, Mir Saman Pishvaee and Seyed Mohammad Seyedhosseini

Given the importance of estimating the demand for relief items in earthquake disaster, this research studies the complex nature of demand uncertainty in a vehicle routing…

Abstract

Purpose

Given the importance of estimating the demand for relief items in earthquake disaster, this research studies the complex nature of demand uncertainty in a vehicle routing problem in order to distribute first aid relief items in the post disaster phase, where routes are subject to disruption.

Design/methodology/approach

To cope with such kind of uncertainty, the demand rate of relief items is considered as a random fuzzy variable and a robust scenario-based possibilistic-stochastic programming model is elaborated. The results are presented and reported on a real case study of earthquake, along with sensitivity analysis through some important parameters.

Findings

The results show that the demand satisfaction level in the proposed model is significantly higher than the traditional scenario-based stochastic programming model.

Originality/value

In reality, in the occurrence of a disaster, demand rate has a mixture nature of objective and subjective and should be represented through possibility and probability theories simultaneously. But so far, in studies related to this domain, demand parameter is not considered in hybrid uncertainty. The worth of considering hybrid uncertainty in this study is clarified by supplementing the contribution with presenting a robust possibilistic programming approach and disruption assumption on roads.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

Keywords

1 – 10 of 27