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Article
Publication date: 1 September 2002

A. Hernández, Ch. Pinto, J. Albizuri and O. Altuzarra

This paper focuses on the study of finite element (FE) analysis reliability of non‐linear planar structural problems (large strains and plasticity). In this first part, some error…

Abstract

This paper focuses on the study of finite element (FE) analysis reliability of non‐linear planar structural problems (large strains and plasticity). In this first part, some error estimators of the flux projection type have been developed over the strain power density concept. Spatial, temporal and global error estimators are proposed. From this point, the authors analyse the behaviour of different discretization error components as a function of parameters such as load step or the number of degrees of freedom of the FE model. In the second part of this work, several properties of these estimators are checked with the application to some numerical examples.

Details

Engineering Computations, vol. 19 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 October 2004

M.F. Webster, I.J. Keshtiban and F. Belblidia

We introduce a second‐order accurate time‐marching pressure‐correction algorithm to accommodate weakly‐compressible highly‐viscous liquid flows at low Mach number. As the…

Abstract

We introduce a second‐order accurate time‐marching pressure‐correction algorithm to accommodate weakly‐compressible highly‐viscous liquid flows at low Mach number. As the incompressible limit is approached (Ma ≈ 0), the consistency of the compressible scheme is highlighted in recovering equivalent incompressible solutions. In the viscous‐dominated regime of low Reynolds number (zone of interest), the algorithm treats the viscous part of the equations in a semi‐implicit form. Two discrete representations are proposed to interpolate density: a piecewise‐constant form with gradient recovery and a linear interpolation form, akin to that on pressure. Numerical performance is considered on a number of classical benchmark problems for highly viscous liquid flows to highlight consistency, accuracy and stability properties. Validation bears out the high quality of performance of both compressible flow implementations, at low to vanishing Mach number. Neither linear nor constant density interpolations schemes degrade the second‐order accuracy of the original incompressible fractional‐staged pressure‐correction scheme. The piecewise‐constant interpolation scheme is advocated as a viable method of choice, with its advantages of order retention, yet efficiency in implementation.

Details

Engineering Computations, vol. 21 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 14 July 2022

Nishad A. and Sajimon Abraham

A wide number of technologies are currently in store to harness the challenges posed by pandemic situations. As such diseases transmit by way of person-to-person contact or by any…

Abstract

Purpose

A wide number of technologies are currently in store to harness the challenges posed by pandemic situations. As such diseases transmit by way of person-to-person contact or by any other means, the World Health Organization had recommended location tracking and tracing of people either infected or contacted with the patients as one of the standard operating procedures and has also outlined protocols for incident management. Government agencies use different inputs such as smartphone signals and details from the respondent to prepare the travel log of patients. Each and every event of their trace such as stay points, revisit locations and meeting points is important. More trained staffs and tools are required under the traditional system of contact tracing. At the time of the spiralling patient count, the time-bound tracing of primary and secondary contacts may not be possible, and there are chances of human errors as well. In this context, the purpose of this paper is to propose an algorithm called SemTraClus-Tracer, an efficient approach for computing the movement of individuals and analysing the possibility of pandemic spread and vulnerability of the locations.

Design/methodology/approach

Pandemic situations push the world into existential crises. In this context, this paper proposes an algorithm called SemTraClus-Tracer, an efficient approach for computing the movement of individuals and analysing the possibility of pandemic spread and vulnerability of the locations. By exploring the daily mobility and activities of the general public, the system identifies multiple levels of contacts with respect to an infected person and extracts semantic information by considering vital factors that can induce virus spread. It grades different geographic locations according to a measure called weightage of participation so that vulnerable locations can be easily identified. This paper gives directions on the advantages of using spatio-temporal aggregate queries for extracting general characteristics of social mobility. The system also facilitates room for the generation of various information by combing through the medical reports of the patients.

Findings

It is identified that context of movement is important; hence, the existing SemTraClus algorithm is modified by accounting for four important factors such as stay point, contact presence, stay time of primary contacts and waypoint severity. The priority level can be reconfigured according to the interest of authority. This approach reduces the overwhelming task of contact tracing. Different functionalities provided by the system are also explained. As the real data set is not available, experiments are conducted with similar data and results are shown for different types of journeys in different geographical locations. The proposed method efficiently handles computational movement and activity analysis by incorporating various relevant semantics of trajectories. The incorporation of cluster-based aggregate queries in the model do away with the computational headache of processing the entire mobility data.

Research limitations/implications

As the trajectory of patients is not available, the authors have used the standard data sets for experimentation, which serve the purpose.

Originality/value

This paper proposes a framework infrastructure that allows the emergency response team to grab multiple information based on the tracked mobility details of a patient and facilitates room for various activities for the mitigation of pandemics such as the prediction of hotspots, identification of stay locations and suggestion of possible locations of primary and secondary contacts, creation of clusters of hotspots and identification of nearby medical assistance. The system provides an efficient way of activity analysis by computing the mobility of people and identifying features of geographical locations where people travelled. While formulating the framework, the authors have reviewed many different implementation plans and protocols and arrived at the conclusion that the core strategy followed is more or less the same. For the sake of a reference model, the Indian scenario is adopted for defining the concepts.

Details

International Journal of Pervasive Computing and Communications, vol. 19 no. 4
Type: Research Article
ISSN: 1742-7371

Keywords

Article
Publication date: 20 February 2007

Dale Southerton

This article seeks to address differential experiences of the “time squeeze”. It problematises current accounts which explain time pressure as resulting from substantive increases…

Abstract

Purpose

This article seeks to address differential experiences of the “time squeeze”. It problematises current accounts which explain time pressure as resulting from substantive increases in the volume of activities performed in daily life and/or an acceleration of the tempo of daily practices.

Design/methodology/approach

The main data source is in‐depth household interviews, although analysis of data from the 1985 and 1992 Health and Lifestyle Survey and the 1937 “day in the life of diaries” are also examined.

Findings

It is argued that harriedness best captures contemporary temporal experiences. Three forms of harriedness are identified: substantive overload; temporal dis‐organisation; and, temporal density. The latter two forms are characterised by the challenge of coordinating practices within social networks and the difficulty of allocating practices in relation to temporally fixed institutional events.

Originality/value

It is suggested that these two forms of harriedness capture women's experiences more so than men's, and that technologies which facilitate time saving and shifting exacerbate rather than alleviate this temporal conditioning of daily life.

Details

Equal Opportunities International, vol. 26 no. 2
Type: Research Article
ISSN: 0261-0159

Keywords

Article
Publication date: 3 November 2020

K. Satya Sujith and G. Sasikala

Object detection models have gained considerable popularity as they aid in lot of applications, like monitoring, video surveillance, etc. Object detection through the video…

Abstract

Purpose

Object detection models have gained considerable popularity as they aid in lot of applications, like monitoring, video surveillance, etc. Object detection through the video tracking faces lot of challenges, as most of the videos obtained as the real time stream are affected due to the environmental factors.

Design/methodology/approach

This research develops a system for crowd tracking and crowd behaviour recognition using hybrid tracking model. The input for the proposed crowd tracking system is high density crowd videos containing hundreds of people. The first step is to detect human through visual recognition algorithms. Here, a priori knowledge of location point is given as input to visual recognition algorithm. The visual recognition algorithm identifies the human through the constraints defined within Minimum Bounding Rectangle (MBR). Then, the spatial tracking model based tracks the path of the human object movement in the video frame, and the tracking is carried out by extraction of color histogram and texture features. Also, the temporal tracking model is applied based on NARX neural network model, which is effectively utilized to detect the location of moving objects. Once the path of the person is tracked, the behaviour of every human object is identified using the Optimal Support Vector Machine which is newly developed by combing SVM and optimization algorithm, namely MBSO. The proposed MBSO algorithm is developed through the integration of the existing techniques, like BSA and MBO.

Findings

The dataset for the object tracking is utilized from Tracking in high crowd density dataset. The proposed OSVM classifier has attained improved performance with the values of 0.95 for accuracy.

Originality/value

This paper presents a hybrid high density video tracking model, and the behaviour recognition model. The proposed hybrid tracking model tracks the path of the object in the video through the temporal tracking and spatial tracking. The features train the proposed OSVM classifier based on the weights selected by the proposed MBSO algorithm. The proposed MBSO algorithm can be regarded as the modified version of the BSO algorithm.

Article
Publication date: 18 June 2019

Maryam Shafiei Sabet, Ali Asgary and Adriano O. Solis

Responding to emergency incidents by emergency response organizations such as fire, ambulance and police during large disaster and emergency events is very important. The purpose…

Abstract

Purpose

Responding to emergency incidents by emergency response organizations such as fire, ambulance and police during large disaster and emergency events is very important. The purpose of this paper is to provide some insights into response patterns during the 2013 ice storm in the city of Vaughan, Ontario, Canada, using temporal and spatial analyses.

Design/methodology/approach

The City of Vaughan Fire and Rescue Service data set containing all responses to fire and other emergency incidents from January 1, 2009 to December 31, 2016 was used. The 2013 Southern Ontario ice storm occurred from December 20, 2013 to January 1, 2014, and, for this study, December 20–31 is considered the “study period.” Temporal, spatial and spatiotemporal analyses of responses during the study period are carried out and are compared with the same period in other years (2009–2012 and 2014–2016).

Findings

The findings show that temporal patterns of response attributes changed significantly during the 2013 ice storm. Similarly, the spatial pattern of responses during the 2013 ice storm showed some major differences with other years. The spatiotemporal analyses also demonstrate significant variations in responses in the city during different hours of the day in the ice storm days.

Originality/value

This study is the first study to examine the spatiotemporal patterns of responses made by a fire department during the 2013 ice storm in Canada. It provides some insights into the differences between response volumes, temporal and spatial distributions during large emergency events (e.g. ice storm) and normal situations. The results will help in mitigating the number of responses in the future through public education and technological changes. Moreover, the results will provide fire departments with information that could help them prepare for such events by possible reallocation of resources.

Details

International Journal of Emergency Services, vol. 8 no. 3
Type: Research Article
ISSN: 2047-0894

Keywords

Article
Publication date: 1 September 2004

Kevin J. Laverty

For more than two decades both the business press and research in several academic disciplines have seen an extended debate over what has been called “myopia” or “short‐termism”…

5421

Abstract

For more than two decades both the business press and research in several academic disciplines have seen an extended debate over what has been called “myopia” or “short‐termism”. These terms have been used to describe decisions in which firms pursue short‐term gains ( for example, seeking to maximize quarterly profits) at the expense of long term strategies ( for example, investing in basic research or laying the groundwork for new core competencies). Despite the attention to this subject, there remain conflicting positions in the business press and inconclusive evidence from research regarding causes and proposed solutions. This paper proposes that progress may be possible by looking inside firms – addressing how managerial systems and decision‐making processes affect the development of long term strategies. Survey results suggest that systemic elements – organizational culture, processes, and routines – have promised in understanding why firms may undervalue the long term and pay too much attention to the short‐term. This study finds that firms are less likely to undervalue the long term when they are able to manage tradeoffs between short‐term and long term results, and create a climate of trust that allows individuals to weather the short‐term setbacks necessary to achieve long term results.

Details

Management Decision, vol. 42 no. 8
Type: Research Article
ISSN: 0025-1747

Keywords

Article
Publication date: 14 December 2018

Jai Manik, Amaresh Dalal and Ganesh Natarajan

The purpose of this paper is to numerically investigate the effect of various parameters such as density ratio, surface wettabilities and Weber number on the droplet dripping and…

Abstract

Purpose

The purpose of this paper is to numerically investigate the effect of various parameters such as density ratio, surface wettabilities and Weber number on the droplet dripping and detachment process.

Design/methodology/approach

By using algebraic volume of fluid method, the governing equations are solved using a collocated finite volume approach in two-dimensions.

Findings

The results indicate that, for small densities of droplet, it adheres to the surface except when the surface is hydrophobic, while an increase in Weber number or presence of an additional droplet in the vicinity led to detachment.

Originality/value

The paper explores various characteristics of a droplet when two competing forces, namely, gravity and surface tension, act simultaneously. The detachment is observed for a given initial droplet size, as it becomes denser in an uniform gravitational field. The effect of droplet affinity for two droplets is also presented using the simulations.

Details

Engineering Computations, vol. 36 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 25 June 2019

Valery Gitis and Alexander Derendyaev

The purpose of this paper is to offer two Web-based platforms for systematic analysis of seismic processes. Both platforms are designed to analyze and forecast the state of the…

Abstract

Purpose

The purpose of this paper is to offer two Web-based platforms for systematic analysis of seismic processes. Both platforms are designed to analyze and forecast the state of the environment and, in particular, the level of seismic hazard. The first platform analyzes the fields representing the properties of the seismic process; the second platform forecasts strong earthquakes. Earthquake forecasting is based on a new one-class classification method.

Design/methodology/approach

The paper suggests an approach to systematic forecasting of earthquakes and examines the results of tests. This approach is based on a new method of machine learning, called the method of the minimum area of alarm. The method allows to construct a forecast rule that optimizes the probability of detecting target earthquakes in a learning sample set, provided that the area of the alarm zone does not exceed a predetermined one.

Findings

The paper presents two platforms alongside the method of analysis. It was shown that these platforms can be used for systematic analysis of seismic process. By testing of the earthquake forecasting method in several regions, it was shown that the method of the minimum area of alarm has satisfactory forecast quality.

Originality/value

The described technology has two advantages: simplicity of configuration for a new problem area and a combination of interactive easy analysis supported by intuitive operations and a simplified user interface with a detailed, comprehensive analysis of spatio-temporal processes intended for specialists. The method of the minimum area of alarm solves the problem of one-class classification. The method is original. It uses in training the precedents of anomalous objects and statistically takes into account normal objects.

Abstract

Details

Transportation and Traffic Theory in the 21st Century
Type: Book
ISBN: 978-0-080-43926-6

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