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In this study, we discuss three DTN routing protocols, these are epidemic, PRoPHET and spray and wait routing protocols. A special simulator will be used; that is opportunistic network environment (ONE) to create a network environment. Spray and wait has highest delivery rate and low latency in most of the cases. Hence, spray and wait have better performance than others. This analysis of the performance of DTN protocols helps the researcher to learn better of these protocols in the different environment.

Delay-Tolerant Network (DTN) is a network designed to operate effectively over extreme distances, such as those encountered in space communications or on an interplanetary scale. In such an environment, nodes are occasional communication and are available among hubs, and determinations of the next node communications are not confirmed. In such network environment, the packet can be transferred by searching current efficient route available for a particular node. Due to the uncertainty of packet transfer route, DTN is affected by a variety of factors such as packet size, communication cost, node activity, etc.

Spray and wait have highest delivery rate and low latency in most of the cases. Hence, spray and wait have better performance than others.

The primary goal of the paper is to extend these works in an attempt to offer a better understanding of the behavior of different DTN routing protocols with delivery probability, latency and overhead ratio that depend on various amounts of network parameters such as buffer size, number of nodes, movement ratio, time to live, movement range, transmission range and message generation rate. In this study, we discuss three DTN routing protocols: these are epidemic, PRoPHET and spray and wait routing protocols. A special simulator will be used; that is opportunistic network environment (ONE) to create a network environment. Spray and wait have highest delivery rate and low latency in most of the cases. Hence, spray and wait have better performance than others. This analysis of the performance of DTN protocols helps the researcher to learn better of these protocols in the different environment.

Purpose – The chapter provides a comprehensive review of trade-related regulations of genetically modified (GM) food, identifies their main effects, and analyzes the main motivations behind their support.

Methodology/approach – The analysis is substantiated by (a) results from the literature on GM food regulations and (b) comparative statics results from a simplified three-country partial equilibrium welfare and political economic model.

Findings – The analysis shows that in a non-GM producing country, trade-related regulations will benefit producers, but not necessarily consumers. Producers' support is found to be instrumental to push for a ban, for information requirements on shipments, or for mandatory labeling of GM food products. Outside pressure groups will play the role of swing voters in cases where consumers and producers do not agree.

Research limitations/implications – The analytical model is based on simplifying assumptions on the groups and market effects of each regulation. Future research is needed to empirically validate some of the main results.

Originality/value of the chapter – The goal of the chapter is to inform economic and policy researchers on the effects of GM food trade-related regulations. The chapter provides an updated comprehensive overview of the key trade regulations of GM food. It uses a unique model to derive the main welfare effects of GM food regulations. By comparing the effects of GM food regulations in different types of countries for different pressure groups, the findings provide new insights in this area.

The purpose of this paper is to give compiled information on previously applied cotton fabric surface modifications. The paper covered most of the modifications done on cotton fabric to improve its properties or to add some functional properties. The paper presented mostly studied research works that brought a significant surface improvement on cotton fabric.

Different previous works on surface modifications of cotton fabrics such as pilling, wrinkle and microbial resistance, hydrophobicity, cationization, flame retardancy and UV-protection characteristics were studied and their methods of modification including the main findings are well reported in this paper.

Several modification treatments on surface modification of cotton fabrics indicated an improvement in the desired properties in which the modification is needed. For instance, the pilling tendency, wrinkling, microbial degradation and UV degradation drawbacks of cotton fabric can be overcome through different modification techniques.

To the best of the author’s knowledge, there are no compressive documents that covered all the portions presented in this review. The author tried to cover the surface modifications done to improve the main properties of cotton fabric.

This paper aims to describe a multi-scenario assessment of the seismogenic tsunami hazard for Bangladesh from active subduction zones in the Indian Ocean region. Two segments of the Sunda arc, namely, Andaman and Arakan, appear to pose a tsunamigenic seismic threat to Bangladesh.

High-resolution numerical simulations of tsunami propagation toward the coast of Bangladesh have been carried out for eight plausible seismic scenarios in Andaman and Arakan subduction zones. The numerical results have been analyzed to obtain the spatial variation of the maximum tsunami amplitudes as well as tsunami arrival times for the entire coastline of Bangladesh.

The results suggest that the tsunami heights are amplified on either side of the axis of the submarine canyon which approaches the nearshore sea off Barisal in the seaboard off Sundarban–Barisal–Sandwip. Moreover, the computed tsunami amplitudes are comparatively higher north of the latitude 21.5o in the Teknaf–Chittagong coastline. The calculated arrival times indicate that the tsunami waves reach the western half of the Sundarban–Barisal–Sandwip coastline sooner, while shallow water off the eastern half results in a longer arrival time for that part of the coastline, in the event of an earthquake in the Andaman seismic zone. On the other hand, most parts of the Chittagong–Teknaf coastline would receive tsunami waves almost immediately after an earthquake in the northern segment of the Arakan seismic zone.

The present assessment includes probabilistic measures of the tsunami hazard by incorporating several probable seismic scenarios corresponding to recurrence intervals ranging from 25 years to over 1,000 years.

This paper aims to examine how board composition, political connections and sustainability practices affect risk-taking and performance of firms.

This paper used secondary data and regression technique to analyse the relationship. A sample consisting of 290 firm-year observations was applied in the analysis.

The findings show that a larger board size contributes to greater financial risk; however, this risk can be reduced with more independent directors in the boardroom. An optimal board size with appropriate number of independent directors is desired, as a large board size can be harmful to firm performance. Politically connected firms also generate lower risk-taking and performance, and the double-edged sword effect of political connections needs to be considered. In terms of sustainability practices, firms have to engage in sustainable development to maximise the firms’ value, not ignoring the vital role of women in strategising business performance. However, the effect of sustainability practices on firms’ risk-taking is still not noticeable.

Even though the sample size is not large because of the limited availability of data, the findings, to a certain extent, could be generalised to emerging markets, as most emerging markets do have similar financial and economic developments.

The findings from this paper can be used to support the implementation of sustainability practices, especially in those countries where sustainability initiatives are yet to be widely accepted.

This is one of the first few studies that examined the effect of non-financial information on risk-taking and performance of firms. This study concludes the positive effect of sustainability practices on firm performance.

Purpose – The chapter examines the international welfare effects of biotech crop adoption, based on a transversal literature review and a case study of the introduction of genetically modified (GM) food crops in Bangladesh, India, Indonesia, and the Philippines.

Methodology/approach – The analysis is based on (a) a review of lessons from the applied economic literature and (b) simulations using an improved multimarket, multicountry, computable general equilibrium (CGE) model, calibrated with productivity hypotheses formulated with local scientists in the four Asian countries.

Findings – Results from the analysis show that, in the absence of trade-related regulations, GM crop adoption generates economic gains for adopting countries and importing non-adopters, that domestic regulations at adopters and especially non-adopters can reduce these gains, and that import regulations in other countries can also affect gains for exporting adopters. The case study illustrates these conclusions, but it also shows that net importers will mostly benefit from adoption in their terms of trade, and that segregation of non-GM crops for export markets can be beneficial if it is not too costly.

Research limitations/implications – The use of a CGE model allows for accounting for cross-sectoral effects, and for regulations affecting bilateral trade flows, but it also has a number of limitations. The model used here, like the ones used in the other papers in the literature, is static, based on an aggregated representation of the global economy (GTAP database), and assumes perfect competition. This means that the absolute results of each scenario may not perfectly represent the actual welfare effects engendered by the adoption of biotech crops. Still, what matters here is the comparison of the relative welfare effects across countries and scenarios. The simulations are also done ex-ante, so, even if the model here was calibrated with country-based data, the results do depend on hypothetical assumptions about the performance of the selected technologies.

Originality/value of the paper – The chapter aims to illustrate the welfare effects generated by GM crops for adopters, non-adopters, in a segmented and regulated international market. Unlike other papers, the review section provides key transversal lessons from the literature, accounting for results from both partial equilibrium and CGE model studies. The empirical application focuses on four populous Asian countries that have been largely left out of the literature. The model used in the simulation presents a number of improvement from the CGE literature on GM crops, including partial adoption, factor-biased productivity shock in each adopting country, GM labeling regulations modeled as trade filters, and the inclusion of costly non-GM segregation as observed in the international market.

World agriculture faces enormous challenges in the coming decades. To feed the world adequately in 2050, agricultural production in developing economies will need to nearly double. Incremental production will mainly come from increases in yields or cropping intensities. This chapter focuses on the potential of genetically modified (GM) crops to contribute to agricultural productivity growth and poverty reduction in developing economies. On the basis of a comprehensive literature review of the most recent literature, we aim to shed light on (a) whether GM crops benefit farmers in developing economies and (b) whether GM crops that are currently in the research pipeline address future challenges for agriculture. The first part of the chapter reviews farm-level impacts of GM crops in developing economies. The second part discusses the GM crop research pipeline. GM crop markets are expected to grow in the future but not to change dramatically. We conclude that GM crops benefited farmers, including resource-poor farmers, in developing economies, but benefits are location- and individual-specific. Addressing such complexities will be required to unlock technology potentials.

This paper aims to overcome some of the practical difficulties in assistive control of exoskeletons by developing a new assistive algorithm, called output feedback assistive control (OFAC) method. This method does not require feedbacks from force, electromyography (EMG) or acceleration signals or even their estimated values.

The presented controller uses feedbacks from position and velocity of the output link of series elastic actuators (SEAs) to increase the apparent integral admittance of the assisted systems. Optimal controller coefficients are obtained by maximizing the assistance ratio subjected to constraints of stability, coupled stability and a newly defined comfort measure.

The results confirm the effectiveness of using the inherent properties of SEAs for removing the need for extra controversial sensors in assistive control of 1 degree of freedom (1-DOF) SEA powered exoskeletons. The results also clearly indicate the successful performance of the OFAC method in reducing the external forces required for moving the assisted systems.

As the provided experiments indicate, the proposed method can be easily applied to single DOF compliantly actuated exoskeletons to provide a more reliable assistance with lower costs. This is achieved by removing the need for extra controversial sensors.

This paper proposes a novel assistive controller for SEA-powered exoskeletons with a simple model-free structure and independent of any information about interaction forces and future paths of the system. It also removes the requirement for the extra sensors and transforms the assistive control of the compliantly actuated systems into a simpler problem of position control of the SEA motor.

The purpose of this paper is performance enhancement of ferrite-assisted synchronous reluctance (FASR) motor using multi-objective differential evolution (MODE) algorithm, considering the significant geometric design parameters.

This work illustrates the optimization of FASR motor using MODE algorithm to enhance the performance of the motor considering barrier angular positions, magnet height, magnet axial length, flux barrier angles of the rotor and air gap length. In the optimization routine to determine the performance parameters, generalized regression neural network-based interpolation is used. The results of MODE are validated with multi-objective particle swarm optimization algorithm and multi-objective genetic algorithm.

The design optimization procedure developed in this work for FASR motor aims at achieving multiple objectives, namely, average torque, torque ripple and efficiency. With multiple objectives, it is essential to give the designer the tradeoff between different objectives so as to arrive at the best design suitable for the application. The results obtained in this work justify the application of the MODE approach for FASR motor to determine the various feasible solutions within the bounds of the design.

Analysis, design and optimization of synchronous reluctance motor has been explored in detail to establish its potential for variable speed applications. In recent years, the focus is toward the electromagnetic design of hybrid configurations such as FASR motor. It is in this preview this work aims to achieve optimal design of FASR motor using multi-objective optimization approach.

The results of this work will supplement and encourage the application of FASR motor as a viable alternate for variable speed drive applications. In addition, the application of MODE to arrive at better design solutions is demonstrated.

The approach presented in this work focuses on obtaining enhanced design of FASR motor considering average torque, torque ripple and efficiency as performance measures. The posteriori analysis of optimization provides an insight into the choice of parameters involved and their effects on the design of FASR motor. The efficacy of the optimization routine is justified in comparison with other multi-objective algorithms.

The purpose of this paper is to review different microfinance products and services that can be offered to reduce the financial vulnerabilities of communities at risk. Following a detail literature review, the effectiveness of different forms of microfinance services in creating resilience in the affected communities was analysed and whether they can be applied to mitigate the risk of future disasters was assessed. In addition, the study was conducted to assess whether microcredit can help reduce direct risk exposure of the poor through income smoothing.

This study is based on a review of existing theories.

The notion that most vulnerable communities are financially weak is evident from studies. This study finds that microcredit can help reduce direct risk exposure of poor through income smoothing, while saving can help them recover from the losses of disasters. Our review also suggests that there is no specific model of microfinance services which can have a holistic impact on the financial capacity-building, particularly during the rehabilitation process.

There are different categories of microfinance products with distinct characteristics and associated benefits to the communities. Some of the major microfinance products as identified in this study are, saving products, credit products and insurance products. These products have multidimensional benefits, as there are many approaches adopted by microfinance institutions (MFIs) and clients regarding the use of these products. However this study focuses on the use of these products towards resilience development in the community. Other applications of these products still need to be explored.

There is a need for a comprehensive financial tool that can be effectively applied to expedite the process of rehabilitation and reduce the financial impact of disasters on the community, particularly the poor. Major issues in the context of disasters faced by MFIs to design their products in the affected areas are also highlighted in the study.

The study throws lights on different microfinancial tools such as microloans, microcredits and cash for work, etc. offered by banks and other organizations and highlights their role in the rehabilitation and reconstruction of those affected by disasters in different parts of the world.

This paper contributes to the discourse of microfinance and its social applications in developing countries. It provides original role of microfinance as a tool for creating community resilience to the impacts of disasters.