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Article
Publication date: 8 November 2023

Ignacio Del Rosal

Liner shipping plays a crucial role in facilitating the movement of manufactured goods around the world. While previous literature has shown that liner shipping is an important…

Abstract

Purpose

Liner shipping plays a crucial role in facilitating the movement of manufactured goods around the world. While previous literature has shown that liner shipping is an important trade driver, potential differences across trade routes and world regions have not as yet been explored. This paper examines whether the impact of liner shipping on bilateral trade flows differs significantly across world regions, as well as exploring other geographical patterns.

Design/methodology/approach

Using state-of-the-art gravity modelling, this paper investigates the impact of the UNCTAD's Liner Shipping Bilateral Connectivity Index on bilateral trade in manufactured goods using a comprehensive database of disaggregated trade data for the period from 2006 to 2019.

Findings

The results show that the trade effect of liner shipping is greater in long-distance and interregional bilateral flows. For some regions, such as North America and Oceania, the effect is greater than the world average, while for others, such as Africa and South America, the effect is significantly smaller. The trade effects of liner shipping connectivity on the main east–west routes are average, but clear asymmetry emerges when analysing China's inward and outward trade flows separately.

Originality/value

The results of this paper show that the major east–west routes determine the baseline trade effects of liner shipping, demonstrate that some north–south trades such as those involving Oceania generate larger trade effects and confirm that the trade effects of liner shipping can be improved for some world regions such as South America and Africa.

Details

Maritime Business Review, vol. 9 no. 1
Type: Research Article
ISSN: 2397-3757

Keywords

Content available
Article
Publication date: 7 March 2019

Joshua R. Muckensturm and Dave C. Longhorn

This paper introduces a new heuristic algorithm that aims to solve the military route vulnerability problem, which involves assessing the vulnerability of military cargo flowing

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Abstract

Purpose

This paper introduces a new heuristic algorithm that aims to solve the military route vulnerability problem, which involves assessing the vulnerability of military cargo flowing over roads and railways subject to enemy interdiction.

Design/methodology/approach

Graph theory, a heuristic and a binary integer program are used in this paper.

Findings

This work allows transportation analysts at the United States Transportation Command to identify a relatively small number of roads or railways that, if interdicted by an enemy, could disrupt the flow of military cargo within any theater of operation.

Research limitations/implications

This research does not capture aspects of time, such as the reality that cargo requirements and enemy threats may fluctuate each day of the contingency.

Practical implications

This work provides military logistics planners and decision-makers with a vulnerability assessment of theater distribution routes, including insights into which specific roads and railways may require protection to ensure the successful delivery of cargo from ports of debarkation to final destinations.

Originality/value

This work merges network connectivity and flow characteristics with enemy threat assessments to identify militarily-useful roads and railways most vulnerable to enemy interdictions. A geographic combatant command recently used this specific research approach to support their request for rapid rail repair capability.

Details

Journal of Defense Analytics and Logistics, vol. 3 no. 1
Type: Research Article
ISSN: 2399-6439

Keywords

Content available
Article
Publication date: 7 July 2020

Michael Wells, Michael Kretser, Ben Hazen and Jeffery Weir

This study aims to explore the viability of using C-17 reduced-engine taxi procedures from a cost savings and capability perspective.

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Abstract

Purpose

This study aims to explore the viability of using C-17 reduced-engine taxi procedures from a cost savings and capability perspective.

Design/methodology/approach

This study model expected engine fuel flow based on the number of operational engines, aircraft gross weight (GW) and average aircraft groundspeed. Using this model, the research executes a cost savings simulation estimating the expected annual savings produced by the proposed taxi methodology. Operational and safety risks are also considered.

Findings

The results indicate that significant fuel and costs savings are available via the employment of reduced-engine taxi procedures. On an annual basis, the mobility air force has the capacity to save approximately 1.18 million gallons of jet fuel per year ($2.66m in annual fuel costs at current rates) without significant risk to operations. The two-engine taxi methodology has the ability to generate capable taxi thrust for a maximum GW C-17 with nearly zero risks.

Research limitations/implications

This research was limited to C-17 procedures and efficiency improvements specifically, although it suggests that other military aircraft could benefit from these findings as is evident in the commercial airline industry.

Practical implications

This research recommends coordination with the original equipment manufacturer to rework checklists and flight manuals, development of a fleet-wide training program and evaluation of future aircraft recapitalization requirements intended to exploit and maximize aircraft surface operation savings.

Originality/value

If implemented, the proposed changes would benefit the society as government resources could be spent elsewhere and the impact on the environment would be reduced. This research conducted a rigorous analysis of the suitability of implementing a civilian airline’s best practice into US Air Force operations.

Details

Journal of Defense Analytics and Logistics, vol. 4 no. 2
Type: Research Article
ISSN: 2399-6439

Keywords

Open Access
Article
Publication date: 13 February 2020

John A. Kearby, Ryan D. Winz, Thom J. Hodgson, Michael G. Kay, Russell E. King and Brandon M. McConnell

The purpose of this paper is to investigate US noncombatant evacuation operations (NEO) in South Korea and devise planning and management procedures that improve the efficiency of…

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Abstract

Purpose

The purpose of this paper is to investigate US noncombatant evacuation operations (NEO) in South Korea and devise planning and management procedures that improve the efficiency of those missions.

Design/methodology/approach

It formulates a time-staged network model of the South Korean noncombatant evacuation system as a mixed integer linear program to determine an optimal flow configuration that minimizes the time required to complete an evacuation. This solution considers the capacity and resource constraints of multiple transportation modes and effectively allocates the limited assets across a time-staged network to create a feasible evacuation plan. That solution is post-processed and a vehicle routing procedure then produces a high resolution schedule for each individual asset throughout the entire duration of the NEO.

Findings

This work makes a clear improvement in the decision-making and resource allocation methodology currently used in a NEO on the Korea peninsula. It immediately provides previously unidentifiable information regarding the scope and requirements of a particular evacuation scenario and then produces an executable schedule for assets to facilitate mission accomplishment.

Originality/value

The significance of this work is not relegated only to evacuation operations on the Korean peninsula; there are numerous other NEO and natural disaster related scenarios that can benefit from this approach.

Details

Journal of Defense Analytics and Logistics, vol. 4 no. 1
Type: Research Article
ISSN: 2399-6439

Keywords

Open Access
Article
Publication date: 1 December 2023

Claudio Columbano, Lucia Biondi and Enrico Bracci

This paper aims to contribute to the debate over the desirability of introducing an accrual-based accounting system in the public sector by examining whether accrual-based…

Abstract

Purpose

This paper aims to contribute to the debate over the desirability of introducing an accrual-based accounting system in the public sector by examining whether accrual-based accounting information is superior to cash-based information in the context of public sector entities.

Design/methodology/approach

This paper applies a quantitative research method to assess the degree of smoothness and relevance of the accrual components of income recorded by 302 entities of the Italian National Health Service (INHS) over the period 2014–2020.

Findings

The analysis reveals that net income is smoother than cash flows as a summary measure of economic results and that accounting for accruals improves the predictability of future cash flows. However, the authors' novel disaggregation of accrual accounts reveals that those accounts that contribute the most to making income smoother than cash flows – noncurrent assets and liabilities – are also those that contribute the least to predicting future cash flows.

Originality/value

The disaggregation of accrual accounts allows to identify the sources of the informational benefits of accrual accounting, and to document the existence of an informational “trade-off” between smoothness and relevance in the context of public sector entities.

Details

Journal of Public Budgeting, Accounting & Financial Management, vol. 35 no. 6
Type: Research Article
ISSN: 1096-3367

Keywords

Content available
Article
Publication date: 1 March 2011

Herbert Sherman, Adva Dinur and Daniel Rowley

In this two-part case, Richard Davis and Stephen Hodgetts, co-owners of D&H Management LLC, are trying to come to terms with changes in the real estate market‐changes that have…

Abstract

In this two-part case, Richard Davis and Stephen Hodgetts, co-owners of D&H Management LLC, are trying to come to terms with changes in the real estate market‐changes that have made their rental homes worth less than their mortgages and at best yielding at most a break-even cash flow. In Part A Davis and Hodgetts are weighing the following options: (1) sell all of the properties, assume a loss (walk away with nothing), and avoid the negative cash flow; (2) walk away from all of the properties, assume a loss (walk away with nothing), and avoid the negative cash flow; (3) delay paying the mortgage on some of the homes, allow these properties, if necessary, to go into foreclosure, and in the interim use the positive cash flow to shore up some of the more positive cash flow homes; (4) contact all of the lenders and try to renegotiate the mortgages so as to have lower monthly rates.

In Part B Davis proposes that he and Hodgetts go their separate ways. Davis walks away with the two properties that have mortgages in his name, while Hodgetts obtains the four properties that have mortgages in his. From Hodgettsʼ perspective this is a losing proposition since (1) he would have to take over the management of four “loser” properties rather than Davisʼs two, an ʼunfairʼ split of the liabilities; (2) he had no interest in managing properties; and (3) he and Davis would be splitting up a long-standing team.

Details

New England Journal of Entrepreneurship, vol. 14 no. 2
Type: Research Article
ISSN: 2574-8904

Open Access
Article
Publication date: 16 October 2023

Emmanuel Dele Omopariola, Abimbola Olukemi Windapo, David John Edwards, Clinton Ohis Aigbavboa, Sunday Ukwe-Nya Yakubu and Onimisi Obari

Previous studies have postulated that an advance payment system (APS) positively impacts the contractor's working capital and is paramount to ensuring an efficient and effective…

Abstract

Purpose

Previous studies have postulated that an advance payment system (APS) positively impacts the contractor's working capital and is paramount to ensuring an efficient and effective project cash flow process. However, scant research has been undertaken to empirically establish the cash flow performance and domino effect of APS on project and organisational performance.

Design/methodology/approach

The epistemological design adopted a positivist philosophical stance augmented by deductive reasoning to explore the phenomena under investigation. Primary quantitative data were collected from 504 Construction Industry Development Board (CIDB) registered contractors (within the grade bandings 1–9) in South Africa. A five-point Likert scale was utilised, and subsequent data accrued were analysed using structural equation modelling (SEM).

Findings

Emergent findings reveal that the mandatory use of an APS does not guarantee a positive project cash flow, an improvement in organisational performance or an improvement in project performance.

Practical implications

The ensuing discussion reveals the contributory influence of APS on positive cash flow and organisational performance, although APS implementation alone will not achieve these objectives. Practically, the research accentuates the need for various measures to be concurrently adopted (including APS) towards ensuring a positive project cash flow and improved organisational and project performance.

Originality/value

There is limited empirical research on cash flow performance and the domino effect of APS on project and organisational performance in South Africa, nor indeed, the wider geographical location of Africa as a continent. This study addresses this gap in the prevailing body of knowledge.

Details

Engineering, Construction and Architectural Management, vol. 31 no. 13
Type: Research Article
ISSN: 0969-9988

Keywords

Open Access
Article
Publication date: 22 November 2023

En-Ze Rui, Guang-Zhi Zeng, Yi-Qing Ni, Zheng-Wei Chen and Shuo Hao

Current methods for flow field reconstruction mainly rely on data-driven algorithms which require an immense amount of experimental or field-measured data. Physics-informed neural…

Abstract

Purpose

Current methods for flow field reconstruction mainly rely on data-driven algorithms which require an immense amount of experimental or field-measured data. Physics-informed neural network (PINN), which was proposed to encode physical laws into neural networks, is a less data-demanding approach for flow field reconstruction. However, when the fluid physics is complex, it is tricky to obtain accurate solutions under the PINN framework. This study aims to propose a physics-based data-driven approach for time-averaged flow field reconstruction which can overcome the hurdles of the above methods.

Design/methodology/approach

A multifidelity strategy leveraging PINN and a nonlinear information fusion (NIF) algorithm is proposed. Plentiful low-fidelity data are generated from the predictions of a PINN which is constructed purely using Reynold-averaged Navier–Stokes equations, while sparse high-fidelity data are obtained by field or experimental measurements. The NIF algorithm is performed to elicit a multifidelity model, which blends the nonlinear cross-correlation information between low- and high-fidelity data.

Findings

Two experimental cases are used to verify the capability and efficacy of the proposed strategy through comparison with other widely used strategies. It is revealed that the missing flow information within the whole computational domain can be favorably recovered by the proposed multifidelity strategy with use of sparse measurement/experimental data. The elicited multifidelity model inherits the underlying physics inherent in low-fidelity PINN predictions and rectifies the low-fidelity predictions over the whole computational domain. The proposed strategy is much superior to other contrastive strategies in terms of the accuracy of reconstruction.

Originality/value

In this study, a physics-informed data-driven strategy for time-averaged flow field reconstruction is proposed which extends the applicability of the PINN framework. In addition, embedding physical laws when training the multifidelity model leads to less data demand for model development compared to purely data-driven methods for flow field reconstruction.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

Open Access
Article
Publication date: 15 August 2023

Saima Ritonummi, Valtteri Siitonen, Markus Salo and Henri Pirkkalainen

The purpose of this study is to investigate the barriers that prevent workers in the software industry from experiencing flow in their work.

Abstract

Purpose

The purpose of this study is to investigate the barriers that prevent workers in the software industry from experiencing flow in their work.

Design/methodology/approach

This study was conducted by using a qualitative critical incident technique-inspired questionnaire.

Findings

The findings suggest that workers in the software industry perceive that the most obvious obstacles to experiencing flow are related to work not presenting enough cognitive challenges and situational barriers related to the characteristics of the job (e.g. workdays having too many interruptions and distractions, timetables often being considered too tight for creative exploration and problem solving and having negative user experiences with development tools).

Originality/value

The findings provide insights into flow barriers, specifically barriers that prevent workers in the software industry from experiencing flow.

Details

Journal of Workplace Learning, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1366-5626

Keywords

Open Access
Article
Publication date: 21 July 2023

Ana Carolina Borges Marques Ribeiro and Silvio Hong Tiing Tai

This study analyzes the role of migrant networks in the migration flows in relation to the educational level of the migrants and economic growth of the states of origin and…

Abstract

Purpose

This study analyzes the role of migrant networks in the migration flows in relation to the educational level of the migrants and economic growth of the states of origin and destination in Brazil.

Design/methodology/approach

Fixed effects estimator applied to microdata.

Findings

The results show migrant networks have a significant and positive impact on migration flows of the different educational levels. The economic growth in the destination state accentuates this effect, while the economic growth in the origin state has distinct impacts according to the educational level of the new migrant.

Originality/value

The authors investigate the importance of migrant networks in the internal immigration within a developing country with large internal movement of people. In Brazil, the socio-economic condition of the population varies considerably in relation to its geography, which explains the country’s large internal migration flows.

Details

EconomiA, vol. 24 no. 2
Type: Research Article
ISSN: 1517-7580

Keywords

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