Search results

The purpose of this paper is to illustrate the benefits of reintroducing traditional grazing systems practices for improving arid rangelands. Grazing is the most extensive land use in southern Tunisia, but the rangelands have suffered many decades of severe degradation due to profound socioeconomic changes and the emergence of an agro-pastoral society in place of the former pastoral one. Traditional grazing systems (gdel and herd mobility), which had historically allowed for grazing deferment and control of grazing livestock were abandoned. Yet grazing management strategies are important tools to sustain integrated livestock rangeland production systems in dry areas in the face of ongoing climate change and human pressure.

This study assesses the revival of traditional best practices of rangeland resting in a representative community. Total plant cover, species composition, flora richness and range production were determined in six rangeland sites subjected respectively to one, two and three years of rest; one and two years of light grazing after rest; and free grazing (control).

Results showed that dry rangelands keep their resilience to the negative effects of climate change once human pressure is controlled. A maximum of two years of rest is enough to sustainably manage the rangelands in southern Tunisia, as this protection showed considerable and positive effects on the parameters scored.

The revival of the traditional best practices under new arrangements adapted to current biophysical and socioeconomic conditions would be an excellent tool to mitigate the negative effects of frequent droughts and reduce the animal feed costs that poor farmers face.

Energy is the major concern in wireless sensor networks (WSNs) for most of the applications. There exist many factors for higher energy consumption in WSNs. The purpose of this work is to increase the coverage area maintaining the minimum possible nodes or sensors.

This paper has proposed multilayer (ML) nodes deployment with distributed MAC (DS-MAC) in which nodes listen time is controlled based on communication of neighbors. Game theory optimization helps in addressing path loss constraints while selecting path toward base stations (BS).

The simulation is carried out using NS-2.35, and it shows better performance in ML DS-MAC compared to random topology in DS-MAC with same number of BS. The proposed method improves performance of network in terms of energy consumption, network lifetime and better throughput.

Energy consumption is the major problem in WSNs and for which there exist many reasons, and many approaches are being proposed by researchers based on application in which WSN is used. Node mobility, topology, multitier and ML deployment and path loss constraints are some of the concerns in WSNs.

Game theory is used in different situations like countries whose army race, business firms that are competing, animals generally fighting for prey, political parties competing for vote, penalty kicks for the players in football and so on.

WSNs find applications in surveillance, monitoring, inspections for wild life, sea life, underground pipes and so on.

Game theory optimization helps in addressing path loss constraints while selecting path toward BS.

Prolonged working in repetitive and awkward postures can result in musculoskeletal disorders among workers involved in labour-intensive jobs like those of brick kiln workers. Unlike other labour-intensive sectors, workers in this particular sector have a lack of awareness about musculoskeletal problems. Therefore, the purpose of this paper is to explore musculoskeletal issues and associated risk-factors among brick kiln workers.

A questionnaire survey was conducted among 217 male and 111 female workers aged between 17 and 53 years. They were employed in traditional brick kiln units situated in Rajasthan, India. Postures were analysed by Rapid Upper Limb Assessment and Rapid Entire Body Assessment methods. Binary logistic regression was used to find the association between musculoskeletal problems and risk-factors.

For the mould evacuating task, wrist (76.2 per cent) and lower back (56 per cent) issues were the most frequently reported musculoskeletal problems, while in spading task, lower back (62.4 per cent) and shoulder (57.7 per cent) problems were prominent. Musculoskeletal symptoms in one or more body regions were associated with personal and work-related factors including the type of task and experience.

Kiln workers are exposed to high musculoskeletal and postural risks, particularly in spading and mould filling tasks. To reduce these risks, ergonomic interventions are needed.

It is recognised that the musculoskeletal health of brick kiln workers is a cause for concern. The present study provides the evidence of the prevalence of musculoskeletal symptoms experienced by brick kiln workers and the association of symptoms with various risk-factors, which has not been addressed in previous studies.

This study aims to focus on exploring the construction productivity of building projects under the influence of potential factors. The three primary purposes are (1) determining critical factors affecting construction productivity; (2) identifying causal relationship and occurrence probability of these factors to develop a Bayesian network (BN) model; and (3) validating the accuracy of predictions from the proposed BN model via a case study.

A conceptual framework that includes three performance stages was used. Twenty-two possible factors were screened from a comprehensive literature review and evaluated through expert opinions. Data were collected using a structured questionnaire-based survey and case-study-based survey. The sampling methods were based on non-probability sampling.

Worker characteristic-related factors significantly affect labour productivity for a construction task. Construction productivity is dominated by the working frequency of workers (overtime), complexity of the task, level of technology application and accidents. Labour productivity is defined as nearly 50% of the baseline productivity using the BN model created by the caut 2sal relationship and probability of factors. The prediction error of the BN model was 6.6%, 10.0% and 9.3% for formwork (m²/h), reinforcing steel (ton/h) and concrete (m³/h), respectively.

The evaluation or prediction of productivity performance has become a necessary topic for research and practice.

Managers and practitioners in the construction sector can utilise the outcome of this study to create good productivity management policies for their prospective projects.

Worker-related characteristics are dominant among critical factors affecting labour productivity for a construction task; the proposed BN-based predictive model is built based on these critical factors. The BN approach is highly accurate for construction productivity prediction. The findings of this study can fill gaps in the construction management body of knowledge when modelling construction productivity under the effects of multiple factors and using a simple probabilistic graphic tool.

Operations Management

MBA/Post Graduate

This case attempts to highlight a very common resource allocation dilemma in a real-life scenario. The majority of today’s problems are solved by the methodology of trial and error. This case shows how a generic trial-and-error solution, if buttressed by a proper quantitative methodology, can have substantial impact on the bottom-line of an organization. The case concentrates on three disparate focus areas in a didactic fashion, namely, the ability to retrieve raw data and convert it into a utilizable form if a quantitative method is to be applied; the ability to comprehend the resource constraints of a typical real-life situation; and the skill required to develop and solve an optimization problem in Excel Solver, a product which can easily be accessed by any practitioner.

Expected learning outcomes are as follows: students learn to formulate a Mixed-Integer programming model; to interpret optimal solutions and appreciate the application of “Optimization”; to recommend a resource allocation strategy; and to understand the importance of cost minimization in organizations.

Teaching Notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

CSS: 9: Operations and Logistics

Looks in depth at Romania’s Labour Code and lists out in more detail all the relevant points, to show how employees and employers may work better together without conflict, Using guidelines from the European Union. Uses countries as a flagstaff for what could be done to improve matters for temporary employees.

Heat stress, having caused preventable and lamentable deaths, is hazardous to construction workers in the hot and humid summers of Hong Kong. The purpose of this paper is to develop a heat stress model, based on the Wet Bulb Globe Temperature (WBGT) index.

Field studies were conducted during the summer time in Hong Kong (July to September 2010). Based upon 281 sets of synchronized meteorological and physiological data collected from construction workers in four different construction sites between July and September 2010, physiological, work‐related, environmental and personal parameters were measured to construct and verify the heat stress model.

It is found that drinking habit, age and work duration are the top three significant predictors to determine construction workers' physiological responses. Other predictors include percentage of body fat, resting heart rate, air pollution index, WBGT, smoking habit, energy consumption, and respiratory exchange rate. The accuracy of the model is verified against data which have not been used in developing the model. The accuracy of the heat stress model is found to be statistically acceptable (Mean Absolute Percentage Error=5.6 percent, Theil's U inequality coefficients=0.003).

Based on these findings, appropriate work‐rest pattern can be designed to safeguard the well being of workers when working in a hot and humid environment.

The model reported in this paper provides a more scientific and reliable prediction of the reality which may benefit the industry to produce solid guidelines for working in hot weather.

In line with the IFSB and BCBS methodology, the purpose of this study is to undertake a comparative analysis of dual banking systems for asset-liability management (ALM) practices with the duration gap, in Islamic Commercial Banks (ICBs) and Conventional Commercial Banks (CCBs). Based on the research objective, two research questions are developed: How do the duration gaps of ICBs compare with those of similar sized CCBs? Are there any country-specific and regional differences among ICBs in terms of managing their duration gaps?

The research methodology comprises two-stages: stage one uses a duration gap model to calculate the duration gaps of ICBs and CCBs; stage two applies parametric tests. In terms of the duration gap model, the study determines the duration gap with a four-step process. The study selected a sample of 100 banks (50 ICBs and 50 CCBs) from 13 countries for the period 2009-2015.

The paper provides empirical insights into the duration gap and ALM of ICBs and CCBs. The ICBs have more variations in their mean duration gap compared to the CCBs, and they have a tendency for a higher (more) mean duration gap (28.37 years) in comparison to the CCBs (11.79 years). The study found ICBs as having 2.41 times more duration gap compared to the CCBs, and they are exposed to increasing rate of return (ROR) risk due to their larger duration gaps and severe liquidity mismatches. There are significant regional differences in terms of the duration gap and asset-liability management.

Future studies also consider “Off-Balance Sheet” activities of the ICBs, with multi-term duration measures. A larger sample size of 100 ICBs with 10 years’ data after the GFC would be more beneficial to the industry. In addition, the impact of an increasing benchmark rate (e.g. 100, 200 and 300 bps) on the ICBs as per the IFSB 20 per cent threshold can also be established with the duration gap approach to identify the vulnerabilities of the ICBs.

The study makes profound contributions to the literature and suggests various policy recommendations for Islamic banks, regulators, and standard setters of the ICBs, for identifying and measuring the significance of the duration gaps; and management of the ROR risk under Pillar 2 of the BCBS and IFSB, for financial soundness and stability purposes.

To the best of the authors’ knowledge, this is a pioneer study in Islamic banking involving a sample of 100 banks (50 ICBs and 50 CCBs) from 13 countries. The results of the study provide original empirical evidence regarding the estimation of duration gap, and variations across jurisdictions in terms of vulnerability of ICBs and CCBs in dual banking systems.

This paper analyses the collapse of credit booms into soft landings or systemic banking crises.

A discrete-time competing risks duration model is employed to disentangle the factors behind the length of benign and harmful credit booms.

The results show that economic growth and monetary authorities play the major role in explaining the differences in the length and outcome of credit booms. Moreover, both types of credit expansions display positive duration dependence, i.e. both are more likely to end as they grow older, but hard landing credit booms have proven to be longer than those that land softly.

This paper contributes to our understanding of what affects the length of credit booms and why some end up creating havoc and others do not. In particular, it calls the attention to the important role that Central Bank independence plays regarding credit booms length and outcome.