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Optimal clean-up procedures lie at the heart of the closeout phase of construction projects under contract law. However, due to its complexity involving multiple issues, potentially unfulfilled contractual obligations, performance claims and counter-claims, combined with consequently deteriorating stakeholder relationships, the management of closeouts is fraught with difficulties leading to suboptimal outcomes. This is particularly true where general contractor (GC) organizations do not have a claims management office (CMO) dedicated to improving such suboptimal clean-up outcomes. Thus, this study aims to develop a model by which CMOs’ may effectively manage the clean-up phase in an environment of closeout claims.

X-inefficiency theory was utilized as the theoretical lens guiding this study. The theory helps identify closeout strategies implemented by a GC, which manages completion claims through a CMO. Data were received and analyzed from a large GC, which served as the firm case study. In this case, managing the closeout completion claims was the main function of the CMO.

The average delay of closeout completion was four times greater than construction phase delays. The GC results highlighted the “economic destruction tsunami of projects,” as a root cause for these completion delays. Wrap-up activities under contract law are identified, including within the domains of statements of completion, project handover and debt settlement. Behavior strategies are also defined, including relational and contractual approaches. Moreover, a process for improving closeout claim performance is described, comprising project closeout identification, rational intra-firm behavior, closeout completion and program closeout practice.

Findings from this work can significantly contribute in X-inefficiency theory in relation to how a decrease of X-inefficiency will lead to better closeout claim performance. It also offers practical insights into how best to minimize delayed closeout completion while providing valuable lessons for stakeholders in complex infrastructure projects. Further, a model is developed that may be utilized by owners, consultancies, designers and other contractor organizations in an effort to improve closeout claim performance.

Legal remedies are incorporated into international construction joint ventures (ICJVs) to mitigate contractual breaches. The effectiveness of remedies is predicated on two conditions; the comprehensiveness of the contract and its enforceability within the jurisdiction of interpretation. Relational-related weaknesses contribute to contracting parties placing a premium on the contract's capacity for mediating the relationship. However, contracts are not always enforceable. This study aims to examine means by which joint venture relational governance can be maintained under conditions of minimal legal recourse.

A relational contracting (RC) theory was used as the theoretical underpinning of the paper. Data were collected and analyzed following a multiple-case study approach from case projects in which ICJVs' was used.

The findings reveal (1) 17 relational and contractual governance problems; the main six being contractual flexibility, contractual joint venture system, contract reviewing, project conflict, national culture and leader–follower transgressions; (2) relational and contractual governance problems are managed differently, depending on financing sources and partners' national culture; and (3) that a developed RC-based framework comprising four stages is able to facilitate relational and contractual governance in ICJVs.

This study is novel in providing a guided approach to developing non-legal remedies for the mitigation of contractual breaches in ICJVs, grounded in theory and contextualized for the construction sector.

Public–private partnerships (PPPs) are notoriously prone to disputes among stakeholders, some of which may unduly jeopardize contract performance. Contract disputes arising in Iran are often due to inefficiency of PPP concession agreements and practice. This study presents a causal-predictive model of the root causes and preventive measures for inter-organization disputes to enhance the likelihood of achieving desirable performance in PPP projects.

A theoretical “causal-predictive” model was developed with fourteen hypotheses based on extant literature and contractual agency theory, which resulted in the creation of a pool of 110 published items. Data were obtained from a questionnaire survey with 75 valid responses, completed by 4 stratified groups of Iranian PPP experts. Partial least square structural equation modeling (PLS-SEM) was used for validating the proposed model via a case study.

Results reveal that the main three factors of PPP desirable performance are as follows: on-time project completion, high quality of activities/products and services for public satisfaction. Further, the most influential factors of the lifecycle problems, construction stage, and preferred risk allocation included risk misallocation, improper payment mechanism and failure to facilitate a timely approval process.

For researchers, the findings contribute to the theory of contractual agency; specifically, how different influences among the model's elements lead to better PPP performance. In practical terms, proposed outcome-based strategies will inform PPP stakeholders to avoid dispute occurrence and thus improve the time, quality and services of projects.

Delivery management of perishable products such as blood in a supply chain is a considerable issue such that the last-mile delivery, which refers to deliver goods to the end user as fast as possible takes into account as one of the most important, expensive and, polluting segments in the entire supply chain. Regardless of economic challenges, the last-mile delivery faces social and environmental barriers to continuing operations while complying with environmental and social standards, therefore incorporating sustainability into last-mile logistic strategy is no longer an option but rather a necessity. Accordingly, the purpose of this paper is to consider a last-mile delivery in a blood supply chain in terms of using appropriate technologies such as drones to assess sustainability.

The authors discuss the impact of drone technology on last-mile delivery and its importance in achieving sustainability. They focus on the effect of using drones on CO₂ emission, costs and social benefits by proposing a multi-objective mathematical model to assess sustainability in the last-mile delivery. A preemptive fuzzy goal programming approach to solve the model and measure the achievement degree of sustainability is conducted by using a numerical example to show the capability and usefulness of the suggested model, solution approach and, impact of drone technology in achieving all three aspects of sustainability.

The findings illustrate the achievement degree of sustainability in the delivery of blood based on locating distribution centers and allocating drones. Moreover, a comparison between drones and conventional vehicles is carried out to show the preference of using drones in reaching sustainability. A sensitivity analysis on aspects of sustainability and specifications of drone technology is conducted for validating the obtained results and distinguishing the most dominant aspect and parameters in enhancing the achievement degree of sustainability.

To the best of the authors’ knowledge, no research has considered the assessment of sustainability in the last-mile delivery of blood supply chain with a focus on drone technology.

The purpose of this study is two phase modeling of Water/Cu nanofluid forced convection in different arrangements of elliptical tube banks in a two-dimensional space.

The arrangements of tube banks have been regarded as equal spacing triangle (ES), equilateral triangle (ET) and the rotated square (RS). The obtained results indicate that, among the investigated arrangements, the RS arrangement has the maximum value of heat transfer with cooling fluid. Also, the changes of Nusselt number and the local friction factor are under the influence of three main factors including volume fraction of slid nanoparticles, the changes of fluid velocity parameters on the curved surface of tube and flow separation after crossing from a specified angle of fluid rotation.

In Reynolds number of 250 and in all arrangements of the tube banks, the behavior of Nusselt number is almost the same and the separation of flow happens in almost 155-165 degrees from fluid rotation on surface. In RS arrangement, due to the strength of vortexes after fluid separation, better mixture is created and because of this reason, after the separation zone, the level of local Nusselt number graph enhances significantly.

In this research, the laminar and two-phase flow of Water/Cu nanofluid in tube banks with elliptical cross section has been numerically investigated in a two-dimensional space with different longitudinal arrangements. In this study, the effects of using nanofluid, different arrangements of tube banks and the elliptical cross section on heat transfer and cooling fluid flow among the tube banks of heat exchanger have been numerically simulated by using finite volume method.

This study aims to review the results of relevant studies to shed light on social trust-building in different contexts and the factors that affect it in disaster risk management.

This systematic review was conducted using the Preferred Reporting Items for Systematic reviews and Meta-Analyses model. The study keywords were searched for in PubMed, Scopus and Web of Science databases on August 2021. The inclusion criteria were English-written articles published in social trust and disaster relief efforts. Exclusion criteria were lack of access to the full text and article types such as nonoriginal articles.

Out of 1,359 articles found, 17 articles were included in the final analysis using four general categories: six articles on the role of local government in trust-building (local governments), five articles on the role of social media in trust-building (social media), four articles on the role of social capital in trust-building (social capital) and two articles on the importance of community participation in trust-building (community participation).

Understanding the role of social trust and the factors which influence it will help the development of community-based disaster risk management. Therefore, disaster management organizations and other relief agencies should take the findings of this study into account, as they can help guide policymaking and the adoption of strategies to improve public trust and participation in comprehensive disaster risk management. Further studies recommended understanding people’s experiences and perceptions of social trust, relief and disaster preparedness.

The purpose of this paper is to assess the perceived level of Jordanian nurses’ competencies in offering care to the community during a disaster.

A correlational descriptive design was used to assess nurses’ competencies in offering care for the community during a disaster.

A total of 370 nurses (55 % males) aged 25−55 agreed to participate. The mean score of competencies of nurses who offer care to the community during the disaster was 2.11 (SD = 0.59) points. The results of correlation coefficient tests revealed a significant positive correlation between stated competencies level and nurses’ sex, receiving disaster education and training with rpb (371) = 0.13, p < 0.01; rpb (598) = 0.15, p = 0.004; rpb (598) = 0.21, p < 0.001, respectively. Furthermore, the “care of communities” subscale had a weak positive correlation with the.

Nurses play a critical role in disaster response. However, there was a gap in nurses’ competencies for disaster, which shows there is a crucial need to include disaster management courses in the nursing curriculum and update disaster management courses in hospitals based on nurses’ needs to improve their competencies during disasters.

Increasing heat transfer rate in spiral heat exchangers is possible by using conventional methods such as increasing number of fluid passes and counter flowing. In addition, newer ideas such as using pillows as baffles in the path of cold and hot fluids and using nanofluids can increase heat transfer rate. The purpose of this study is to simulate turbulent flow and heat transfer of two-phase water-silver nanofluid with 0-6 Vol.% nanoparticle concentration in a 180° path of spiral heat exchanger with elliptic pillows.

In this simulation, the finite volume method and two-phase mixture model are used. The walls are subjected to constant heat flux of q″ = 150,000 Wm⁻². The inlet fluid enters curves path of spiral heat exchanger with uniform temperature T_in = 300 K. After flowing past the pillows and traversing the curved route, the working fluid exchanges heat with hot walls and then exits from the section. In this study, the effect of radiation is disregarded because of low temperature range. Also, temperature jump and velocity slipping are disregarded. The effects of thermophoresis and turbulent diffusion on nanofluid heat transfer are disregarded. By using finite volume method and two-phase mixture model, simulations are performed.

The results show that the flow and heat transfer characteristics are dependent on the height of pillows, nanoparticle concentration and Reynolds number. Increasing Reynolds number, nanoparticle concentration and pillow height causes an increase in Nusselt number, pressure drop and pumping power.

Turbulent flow and heat transfer of two-phase water-silver nanofluid of 0-6 per cent volume fraction in a 180° path of spiral heat exchanger with elliptic pillows is simulated.

The purpose of this paper is to evaluate the effect of titanium oxide (TiO₂) and yttrium oxide (Y₂O₃) nanoparticles-reinforced pure aluminium (Al) on the mechanical properties of hybrid aluminium matrix nanocomposites (HAMNCs).

The HAMNCs were fabricated via a vacuum die-assisted stir casting route by a two-step feeding method. The varying weight percentages of TiO₂ and Y₂O₃ nanoparticles were added as 2.5, 5, 7.5 and 10 Wt.%.

Scanning electron microscope images showed the homogenous dispersion of nanoparticles in Al matrix. The tensile strength by 28.97%, yield strength by 50.60%, compression strength by 104.6% and micro-hardness by 50.90% were improved in HAMNC1 when compared to the base matrix. The highest values impact strength of 36.3 J was observed for HAMNC1. The elongation % was decreased by increasing the weight percentage of the nanoparticles. HAMNC1 improved the wear resistance by 23.68%, while increasing the coefficient of friction by 14.18%. Field emission scanning electron microscope analysis of the fractured surfaces of tensile samples revealed microcracks and the debonding of nanoparticles.

The combined effect of TiO₂ and Y₂O₃ nanoparticles with pure Al on mechanical properties has been studied. The composites were fabricated with two-step feeding vacuum-assisted stir casting.