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Article
Publication date: 2 May 2017

Bogdan Fabianski and Krzysztof Zawirski

The paper is concerned about parameter adaptation of a novel, simplified and nonlinear switched reluctance motor (SRM) model. The purpose of the presented on-line procedure is to…

Abstract

Purpose

The paper is concerned about parameter adaptation of a novel, simplified and nonlinear switched reluctance motor (SRM) model. The purpose of the presented on-line procedure is to give an opportunity to set the model parameters’ values to obtain a relatively good convergence with the real control object. This is important when a reference model is used for control (e.g. optimal) or object state classification (e.g. fault detection) purposes. The more convergent the real object model is, the better operation quality may be expected.

Design/methodology/approach

In the paper, a 12/8 pole’s SRM as a control object is analyzed. The model equations were verified experimentally by comparing phase current model estimations with reference (measured) ones at different operational points. Differential equations of motor winding currents were chosen as an approximation function in the fitting (parameter adaptation) process using the Newton and Gauss–Newton methods. The structure of the adaptation system is presented along with the implementation in simulation environment.

Findings

It was confirmed in the simulation tests that Newton and Gauss–Newton methods of nonlinear model parameters’ adaptation may be used for the SRM. The introduced fitting structure is well suited for implementation in real-time, embedded systems. The proposed approximation function could be used in process as an expansion to Jacobian and Hessian matrices. The χ2 (chi2) coefficient (commonly used to measure the quality of the signal fitting) reduced to a low value during the adaptation process. Another introduced quality coefficient shows that the Newton method is slightly better in scope of the entire adaptation process time; however, it needs more computational power.

Research limitations/implications

The proposed structure and approximation function formula in the parameters’ adaptation system is appropriate for sinusoidal distribution of the motor phase inductance value along the rotor angle position. The inductance angular shape is an implication of the mechanical construction – with appropriate dimensions and materials used. In the presented case, the referenced model is a three-phase SRM in 12/8 poles configuration used as a main drive part of Maytag Neptune washing machine produced by Emerson Motors.

Practical implications

The presented method of parameter adaptation for novel, simplified and nonlinear SRM model provides an opportunity for its use in embedded, real-time control systems. The convergent motor model, after the fitting procedure (when the estimations are close to the measurements from real object), may be used for solving many well-known control challenges such as detection of initial rotor position, sensorless control, optimal control, fault-tolerant control end in fault detection (FD) systems. The reference model may be used in FD in the way of deducing signals from the difference between the estimated and measured ones.

Originality/value

The paper proposed a new system of parameter adaptation for the evaluated nonlinear, simplified 12/8 poles SRM model. The relative simplicity of the proposed model equations provides the possibility of implementing an adaptation system in an embedded system that works in a real-time regime. A Two adaptation methods – Newton and Gauss–Newton – have been compared. The obtained results shown that the Newton fitting method is better in the way of the used quality indicator, but it consumes more computational power.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 5 June 2017

Jan Pries-Heje and Richard Baskerville

The purpose of this paper is to use translation theory to develop a framework (called FTRA) that explains how companies adopt agile methods in a discourse of fragmentation and…

2243

Abstract

Purpose

The purpose of this paper is to use translation theory to develop a framework (called FTRA) that explains how companies adopt agile methods in a discourse of fragmentation and articulation.

Design/methodology/approach

A qualitative multiple case study of six firms using the Scrum agile methodology. Data were collected using mixed methods and analyzed using three progressive coding cycles and analytic induction.

Findings

In practice, people translate agile methods for local settings by choosing fragments of the method and continuously re-articulating them according to the exact needs of the time and place. The authors coded the fragments as technological rules that share relationships within a framework spanning two dimensions: static-dynamic and actor-artifact.

Research limitations/implications

For consistency, the six cases intentionally represent one instance of agile methodology (Scrum). This limits the confidence that the framework is suitable for other kinds of methodologies.

Practical implications

The FTRA framework and the technological rules are promising for use in practice as a prescriptive or even normative frame for governing methodology adaptation.

Social implications

Framing agile adaption with translation theory surfaces how the discourse between translocal (global) and local practice yields the social construction of agile methods. This result contrasts the more functionalist engineering perspective and privileges changeability over performance.

Originality/value

The use of translation theory and the FTRA framework to explain how agile adaptation (in particular Scrum) emerges continuously in a process where method fragments are articulated and re-articulated to momentarily suit the local setting. Complete agility that rapidly and elegantly changes its own environment must, as a concomitant, rapidly and elegantly change itself. This understanding also elaborates translation theory by explaining how the articulation and re-articulation of ideas embody the means by which ideas travel in practice.

Details

Information Technology & People, vol. 30 no. 2
Type: Research Article
ISSN: 0959-3845

Keywords

Open Access
Article
Publication date: 11 October 2021

Phuong T.A. Huynh, Ngoan D. Le, Sen T.H. Le and Thang N. Tran

This paper aims to examine adaptive livelihood strategies used by small-scale fishing households in the two coastal communities in Central Vietnam under the context of climate…

2497

Abstract

Purpose

This paper aims to examine adaptive livelihood strategies used by small-scale fishing households in the two coastal communities in Central Vietnam under the context of climate change-related stressors.

Design/methodology/approach

Field data were collected through mixed quantitative and qualitative methods including a review of secondary data, key-informant interviews, group discussions and household surveys with 300 sampled fishing households. The qualitative data support the analysis and discussion of quantitative data.

Findings

The results showed local households’ perception of the presence and influence of multiple non-climate and climate stressors on their fishery-based livelihoods in terms of employment and income in many ways. The affected households exerted to develop a diversity of adaptation methods within and out of fishing to sustain their livelihoods and cover a deficit in household income. The household socio-demographic characteristics particularly education, labour force, fishing equipment and social support played significant importance in characterising the categories of adaptation strategies among the survey households. The role of local governments in creating an enabling environment for local-level adaptation, as well as protecting marine and coastal ecosystems was rather limited despite their recognized importance.

Originality/value

The paper provides an empirical case of how small-scale fishing households in coastal communities in Central Vietnam are adapting to climate-related stressors. It suggests policy should promote livelihood diversification opportunities and address household-level constraints for adaptation. Fisheries management plan is urgently needed to control illegal fishing activities for sustainable use of coastal and marine fishery resources and the appropriate mechanism is important to stretch local governments’ resources for better supporting local-level adaptation.

Details

International Journal of Climate Change Strategies and Management, vol. 13 no. 4/5
Type: Research Article
ISSN: 1756-8692

Keywords

Book part
Publication date: 20 September 2021

Jaewoo Jung, Margaret K. Koli, Christos Mavros, Johnnel Smith and Katy Stepanian

COVID-19 has generated unprecedented circumstances with a tremendous impact on the global community. The academic community has also been affected by the current pandemic, with…

Abstract

COVID-19 has generated unprecedented circumstances with a tremendous impact on the global community. The academic community has also been affected by the current pandemic, with strategy and management researchers now required to adapt elements of their research process from study design through to data collection and analysis. This chapter makes a contribution to the research methods literature by documenting the process of adapting research in light of rapidly changing circumstances, using vignettes of doctoral students from around the world. In sharing their experience of shifting from the initially proposed methodologies to their modified or completely new methodologies, they demonstrate the critical importance of adaptability in research. In doing so, this chapter draws on core literature of adaptation and conducting research in times of crises, aiming to provide key learnings, methodological tips and a “story of hope” for scholars who may be faced with similar challenges in the future.

Details

Research in Times of Crisis
Type: Book
ISBN: 978-1-80071-797-8

Keywords

Article
Publication date: 9 May 2022

Sutinee Chao-Amonphat, Vilas Nitivattananon and Sirinapha Srinonil

This study aims to explain the existing adaptation practices in an urbanized sub-region in the lower Chao Phraya River basin (CPRB) across different scales and dimensions. It…

Abstract

Purpose

This study aims to explain the existing adaptation practices in an urbanized sub-region in the lower Chao Phraya River basin (CPRB) across different scales and dimensions. It offers an overview of water hazards in urban areas along the river basin to discover ways to deal with and recover from hazards via understanding the implications of existing and potential practice for the mitigation of hydrological hazards.

Design/methodology/approach

First, this study collected current adaptation strategies and measures from interview, focus group discussion, workshop organization, etc. to get the current adaptation strategies/measures for the whole CPRB and each specific area. Second, this study identified a set of criteria for evaluation from review of current publications and official reports. Then, the current adaptation strategies/measures were examined through a set of criteria to obtain the current situation of existing practices. Finally, analysis of key challenges and opportunities was done to propose supporting guidelines to reduce hydrological risks and incorporate further adaptation measures needed to boost resilience in the area.

Findings

Adaptation methods should focus on mixed adaptation, which integrates structural, social, organizational and natural adaptation, and to develop multi-dimensional collaboration. The adaption strategy has restricted the usage of some technologies and technical know-how, particularly in the area of climate change. As a result, intentional adaptation to become more inventive is required, to reduce hazards and improve disaster-response capacity. The various adaptation measures should be more integrated or more adaptive and to achieve greater cohesion and mutual benefit of individual measures, such as community-based adaptation or community-driven slum upgrading.

Originality/value

Hydrological risks are wreaking havoc on social, economic and environmental elements, particularly river flood, flash flood and drought in the Asia-Pacific region. Twenty-two existing adaptation options were evaluated with evaluation criteria such as scales of risks/impacts reduction, benefits of environmental and socio-economic and institutional aspects. The findings highlight the current situation of existing practices, key challenges and opportunities, which emphasized on natural-based solutions, raising knowledge and awareness and lessons learned on adaptation of hydrological risks. The existing adaptation measures will be suggested as supporting guidelines and master plans to minimize the hydrological risks.

Details

International Journal of Disaster Resilience in the Built Environment, vol. 15 no. 1
Type: Research Article
ISSN: 1759-5908

Keywords

Open Access
Article
Publication date: 19 September 2017

Wahid Ullah, Takaaki Nihei, Muhammad Nafees, Rahman Zaman and Muhammad Ali

This study aims to investigate risks associated with climate change vulnerability and in response the adaptation methods used by farming communities to reduce its negative impacts…

8372

Abstract

Purpose

This study aims to investigate risks associated with climate change vulnerability and in response the adaptation methods used by farming communities to reduce its negative impacts on agriculture in Pakistan.

Design/methodology/approach

The study used household survey method of data collection in Charsadda district of Khyber Pakhtunkhwa province, involving 116 randomly selected respondents.

Findings

Prevalent crops diseases, water scarcity, soil fertility loss and poor socio-economic conditions were main contributing factors of climate change vulnerability. The results further showed that changing crops type and cultivation pattern, improved seed varieties, planting shaded trees and the provision of excessive fertilizers are the measures adapted to improve agricultural productivity, which may reduce the climate change vulnerability at a household level.

Research limitations/implications

The major limitation of this study was the exclusion of women from the survey due to religious and cultural barriers of in Pashtun society, wherein women and men do not mingle.

Practical implications

Reducing climate change vulnerability and developing more effective adaptation techniques require assistance from the government. This help can be in the form of providing basic resources, such as access to good quality agricultural inputs, access to information and extension services on climate change adaptation and modern technologies. Consultation with other key stakeholder is also required to create awareness and to build the capacity of the locals toward reducing climate change vulnerability and facilitating timely and effective adaptation.

Originality/value

This original research work provides evidence about farm-level vulnerability, adaptation strategies and risk perceptions on dealing with climate-change-induced natural disasters in Pakistan. This paper enriches existing knowledge of climate change vulnerability and adaptation in this resource-limited country so that effective measures can be taken to reduce vulnerability of farming communities, and enhance their adaptive capability.

Details

International Journal of Climate Change Strategies and Management, vol. 10 no. 3
Type: Research Article
ISSN: 1756-8692

Keywords

Article
Publication date: 21 June 2013

William B. Hansen, Melinda M. Pankratz, Linda Dusenbury, Steven M. Giles, Dana C. Bishop, Jordan Albritton, Lauren P. Albritton and Joann Strack

To be effective, evidence‐based programs should be delivered as prescribed. This suggests that adaptations that deviate from intervention goals may limit a program's…

1160

Abstract

Purpose

To be effective, evidence‐based programs should be delivered as prescribed. This suggests that adaptations that deviate from intervention goals may limit a program's effectiveness. This study aims to examine the impact that number and quality of adaptations have on substance use outcomes.

Design/methodology/approach

The authors examined 306 video recordings of teachers delivering “All Stars”, a middle school drug prevention program. Multiple observers coded each recording, noting the number and type of adaptation each teacher made. Each adaptation was given a valence rating. Adaptations that were deleterious to program goals received negative valence ratings; positive ratings were given for adaptations that were likely to facilitate achievement of program goals; neutral ratings were given to adaptations that were expected to have neither a positive nor negative impact on program goals.

Findings

All teachers made adaptations. Teachers were consistent across time in the types of adaptations they made, suggesting each teacher has a personalized style of adapting. Those who made few adaptations, and whose average adaptation was rated as being positive had a higher percentage of students who remained non‐drug users. In contrast, teachers who made many adaptations, whether their average valence rating was positive, neutral or negative, failed to have as many students remain non‐drug users. Measures of fidelity, including quality of delivery and teacher understanding, were related to valence of adaptations, with better performance related to making positive adaptations.

Practical implications

Through training and supervision, teachers should be guided and encouraged to follow programs directions, making few adaptations and ensuring that adaptations that are made advance the goals of intervention. Programs should define acceptable and unacceptable ways they may be adapted.

Originality/value

This study provides significant evidence about the challenges that face disseminated evidence‐based programs.

Book part
Publication date: 31 December 2010

Mikio Ishiwatari

The Intergovernmental Panel on Climate Change (IPCC) IPCC (2007) projects that greater precipitation intensity and variability will increase the risks of flooding in many areas…

Abstract

The Intergovernmental Panel on Climate Change (IPCC) IPCC (2007) projects that greater precipitation intensity and variability will increase the risks of flooding in many areas because of climate change. With climate change already happening, societies worldwide face the parallel challenge of having to adapt to its impacts as a certain degree of climate change is inevitable throughout this century and beyond, even if global mitigation efforts over the next decades prove successful (European Commission, 2007).

Details

Climate Change Adaptation and Disaster Risk Reduction: Issues and Challenges
Type: Book
ISBN: 978-0-85724-487-1

Article
Publication date: 1 June 2011

Quazi M. Mahtab-uz-Zaman

At a time, when there are world-wide calls for sustainable building design and construction focusing on building adaptation and remodeling rather than demolition and replacement…

Abstract

At a time, when there are world-wide calls for sustainable building design and construction focusing on building adaptation and remodeling rather than demolition and replacement, a local system of remodeling and functional adaptation has been applied in many residential and commercial buildings in Bangladesh. Focusing on case studies in Dhaka city where major urban regeneration takes place, building adaptation is an emerging practice where economy has a critical role to play in convincing client, users, designers and builders to encourage the local method of adaptation process to suit the changing need of the occupants.

A case of adaptation of a residential building has been studied to generate an understanding of the local adaptation process. This process is found in many parts of the inner city built environment, which collectively affects urban regeneration process and reshape the urban form of the city and its edge condition. Findings from the exploratory studies suggest that despite the absence of Habraken's support-infill knowledge, the local practice of adaptation can be institutionalized as a sustainable building development process that is more economic and place-responsive approach than rebuilding.

Details

Open House International, vol. 36 no. 2
Type: Research Article
ISSN: 0168-2601

Keywords

Book part
Publication date: 10 April 2006

Georgiy Levchuk, Daniel Serfaty and Krishna R. Pattipati

Over the past few years, mathematical and computational models of organizations have attracted a great deal of interest in various fields of scientific research (see Lin & Carley

Abstract

Over the past few years, mathematical and computational models of organizations have attracted a great deal of interest in various fields of scientific research (see Lin & Carley, 1993 for review). The mathematical models have focused on the problem of quantifying the structural (mis)match between organizations and their tasks. The notion of structural congruence has been generalized from the problem of optimizing distributed decision-making in structured decision networks (Pete, Pattipati, Levchuk, & Kleinman, 1998) to the multi-objective optimization problem of designing optimal organizational structures to complete a mission, while minimizing a set of criteria (Levchuk, Pattipati, Curry, & Shakeri, 1996, 1997, 1998). As computational models of decision-making in organizations began to emerge (see Carley & Svoboda, 1996; Carley, 1998; Vincke, 1992), the study of social networks (SSN) continued to focus on examining a network structure and its impact on individual, group, and organizational behavior (Wellman & Berkowitz, 1988). Most models, developed under the SSN, combined formal and informal structures when representing organizations as architectures (e.g., see Levitt et al., 1994; Carley & Svoboda, 1996). In addition, a large number of measures of structure and of the individual positions within the structure have been developed (Roberts, 1979; Scott, 1981; Wasserman & Faust, 1994; Wellman, 1991).

Details

Understanding Adaptability: A Prerequisite for Effective Performance within Complex Environments
Type: Book
ISBN: 978-1-84950-371-6

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