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The study aims to assess the heater and cooler positional impacts systematically using four different quadrantal cavities filled with hybrid nanofluid, keeping the curved surface adiabatic under the orientated magnetic fields. Both heat transfer and entropy generation analyses are performed for a hybrid nanofluid flow in a quarter circular cavity considering different orientations of magnetic fields. The investigation is focused to assess the heater and cooler positional impacts systematically using four different quadrantal cavities (first to fourth quadrantal cavities), keeping the curved surface always adiabatic. The impacts of pertinent variables like Rayleigh number, Hartmann number and volumetric concentration of hybrid nanofluid on heat transfer characteristics are in consideration with the second law of thermodynamics. The analysis includes the thermal, viscous and magnetic aspects of entropy generation.

After validating against the experimental results, the present work explores numerically following the Galerkin weighted finite element technique. The solution is obtained through an iterative process satisfying the convergence limit of 10⁻⁸ and 10⁻¹⁰ for the maximum residuals and the mass defect, respectively.

It revealed that the mutual exchange of heater-cooler positions on the adjacent straight edges of the quadrant cavity does not have any impact on the flow direction. Although the magnitude of flow velocity enhances, the sidewall plays a decision-making role in the formation of a single circulation vortex. It also shows that thermal entropy production is the main cause behind thermodynamic irreversibility. The second or third quadrantal arrangement could have been opted as the best configuration of the heater-cooler position for achieving superior heat transfer. The Lorentz force plays a great role to moderate the heat transfer process. The maximum entropy generation is located, as expected, at the heating-cooling junction point.

There are plenty of prospects for extension of the present research concept numerically or experimentally, adopting three-dimensional analysis, working fluids, boundary conditions, etc. In fact, the study could be carried out for unsteady or turbulent fluid flow.

As the position of the heated source and cold sink on the enclosure geometry can significantly alter the thermo-fluid phenomena, this kind of analysis is of utmost relevance for the further development of efficient heating/cooling arrangements and proper management of the devices subjected to magnetic field applications. This original contribution could be a potentially valuable source for future research and exploration pertaining to a thermal system or device, like heat exchangers, solar collectors, thermal storage, electronic cooling, food and drying technologies and others.

In the literature, an inadequate number of works have focused on a quadrantal cavity, mostly considering the first quadrant of the circle. However, during practical applications, it is possible that the cavity can take the shape of the other three quadrants too, and the corresponding knowledge on relative performance is still missing. Furthermore, the present investigation includes the existence of magnetic fields at various orientations. The impact analysis of this field-induced Lorentz force on the nanofluid thermal performance is another major contribution from the present work that would enrich the domain knowledge and could be useful for thermal system engineers.

The purpose of this paper is to address a shortfall in the literature dealing with optimal sharing arrangements. In construction projects, where the owner is concerned about multiple project outcomes (cost, time, quality, […]), there exist no guidelines in the literature on what a sharing arrangement should be between the owner and the contractor. This paper gives that arrangement, under defined risk assumptions on the contractor (risk averse ranging to risk neutral) and the owner (risk neutral). The sharing aligns the contractor's interests with those of the owner.

The results are based on solving a constrained maximisation problem involving the expected utilities of both the owner and contractor. Construction practitioners were interviewed in a designed experiment to validate the results.

It is demonstrated that, at the optimum, the proportions of outcomes sharing to the contractor should be higher for outcomes with lower effort cost and a lower level of uncertainty, and by increasing the correlation between outcomes, the fixed component of the contractor’s fee should increase and the proportions to the contractor should decrease.

The theoretical results assume that the contractor is risk-averse ranging to risk-neutral, and that the owner is risk-neutral. The theory is supported through conducting an empirical study based on interviewing a sample of practitioners working for medium-sized contractors, and hence the support is limited to similar situations, until further data are assembled.

By providing a broader understanding of sharing arrangements within contracts, a contribution is made to the current practice of contracts management. The results may be used in the design of contracts, or as benchmarks, by which contracts designed differently, may be compared.

The results address a shortfall in the literature and are an original solution to establishing an optimal multiple-outcome sharing arrangement.

The purpose of this paper is to demonstrate the theoretical relationship between the layout of four‐sensor dynamic acoustic array tracking system and systematic observation accuracy, and provide an algorithm to determine the optimal arrangement of four‐sensor acoustic array and an indicator to evaluate acoustic array system measurement accuracy.

In the present paper, the measurement principle of the four‐sensor dynamic acoustic array tracking system is analyzed, and the system observation model and the conversion relationship between models are established. Subsequently, the optimization algorithm for the four‐sensor dynamic acoustic array is deduced, the theoretical optimal arrangement of the four‐sensor dynamic acoustic array tracking measurement system is obtained based on the optimal position dilution of precision function (PDOPF) of 2D target, and the static experimental study on sound‐source bearing estimation is designed. The theoretical results are compared with the experimental results of the present study.

The measurement accuracy of the four‐sensor dynamic acoustic array tracking system is largely dependent on the layout of the acoustic sensor. Theoretical studies and experimental results demonstrated that an optimal PDPOF can be used to analyze the rationality of the layout. It can also serve as an indicator for the layout of the four‐sensor dynamic acoustic array tracking system.

The PDOPF value is presented as an indicator for the evaluation of the four‐sensor dynamic acoustic array systematic observation accuracy based on theoretical analysis. The feasibility of the indicator and the rationality of the sensor layout in practical engineering application are verified through experimental studies on sound‐source bearing estimation. The higher the PDOPF value is, the lower the accuracy of the system will be.

The purpose of this paper is to search the optimal arrangement scheme of random motion accuracy of joints for optimal synthesis of pose repeatability which can make robot design more reasonable and reduce the development cost of robots.

In this paper, a mathematical model of pose repeatability, which includes positioning repeatability and orientation repeatability of robots, is established. According to the ISO 9283 standard, an optimal synthesis method of pose repeatability for collaborative robots is introduced, and three optimization objective functions are proposed. The optimization model is solved by using numerical analysis software, and the optimal arrangement scheme of random motion accuracy of joints is obtained which meets the requirements of pose repeatability of robot.

It is found that, in three optimization objective functions, the single-objective evaluation function of maximization of joint motion error is more suitable for optimal synthesis of pose repeatability. In practice, due to the safety factor, the test results of pose repeatability are better than the results of optimal synthesis of pose repeatability.

This method makes robot design more reasonable and reduces the development cost of robots.

This work is the first time to optimize the orientation repeatability of collaborative robots. Because the pose repeatability of most robots is tested by the ISO 9283 standard, so this method which is based on this standard is more suitable for the performance requirements of robot products.

This paper aims to improve shearer positioning accuracy. Shearer positioning using an inertial navigation system (INS) is a highly useful technology; however, positioning accuracy is seriously hindered by INS attitude error, particularly heading drift.

A shearer positioning model with double-INS based on extended Kalman filter was proposed. The constant distance between two INSs (INS 1 and INS 2) was selected as the observation vector. Allan variance was used to identify the noise type of the vertical-axis gyroscope, and the stochastic process of heading drift for two INSs was obtained and divided into incongruous drift and concurrent drift.

Simulation was then carried out to determine the optimal arrangement of the two INSs. For incongruous drift, the optimal arrangement satisfied the condition that the line connecting INS 1 and INS 2 was perpendicular to the shearer lateral axis (in the shearer coordinate frame) and parallel to the east-north plane (in the east-north-up coordinate frame). Under optimal arrangement, the positioning accuracy increased against the distance between INS 1 and INS 2. For concurrent drift, the double-INS positioning model had no effect. Under the circumstances, the number of INSs should be increased so that the uncertainty of INS drift was reflected as much as possible.

A new double-INS positioning model was proposed with the constant distance between the two INSs. The optimal arrangement for double-INS was obtained.

The aim of this paper is to develop a theory of sharecropping with cost sharing after allowing for an explicit role of a creditor. In the tenancy literature, the prevalence of sharecropping has remained an important issue. While most contributions have focussed only on output sharing, very few have studied the issue of cost sharing. Besides, the existing models have considered interactions only between a landowner and a tenant. The purpose of this paper is to extend this setup to a third player – creditor.

The authors adopt a static contract approach with full information and no uncertainty and model possible credit‐cum‐tenancy arrangements among a money‐lender, a landowner and a tenant under the restrictions that the money‐lender cannot charge a lump‐sum fee and the input choices are left with the tenant.

It is shown that all Pareto optimal arrangements between a creditor, a landowner and a tenant must involve interest rate discrimination between the tenant and the landowner and a share tenancy with cost sharing, or a fixed rent tenancy with cost sharing, or a mixture of the two. None of the polar contracts – wage or rent – is possible. Lending schemes that feature credit rationing or credit delegation can implement some Pareto efficient outcomes.

The model developed in the paper presents a framework for studying various tripartite arrangements observed in rural economies of developing countries. Also, it provides a benchmark for studying contracts under asymmetric information and uncertainty.

The purpose of this study is investigating the effect of using multi-phase nanofluids, Rayleigh number and baffle arrangement simultaneously on the heat transfer rate and Predict the optimal arrangement type of baffles in the differentiation of Rayleigh number in a 3D enclosure.

Simulations were performed on the base of the L25 Taguchi orthogonal array, and each test was conducted under different height and baffle arrangement. The multi-phase thermal lattice Boltzmann based on the D3Q19 method was used for modeling fluid flow and temperature fields.

Streamlines, isotherms, nanofluid volume fraction distribution and Nusselt number along the wall surface for 104 < Ra < 108 have been demonstrated. Signal-to-noise ratios have been analyzed to predict optimal conditions of maximize and minimize the heat transfer rate. The results show that by choosing the appropriate height and arrangement of the baffles, the average Nusselt number can be changed by more than 57 per cent.

The value of this paper is surveying three-dimensional and two-phase simulation for nanofluid. Also using the Taguchi method for Predicting the optimal arrangement type of baffles in a multi-part enclosure. Finally statistical analysis of the results by using of two maximum and minimum target Function heat transfer rates.

With recent shifts in market forces driven by food safety and quality concerns, managers in the Brazilian beef processing industry are forced to reevaluate their procurement arrangements with cattle producers. The purpose of this paper is to provide insight on the effect of live-weight (LW) and dead-weight (DW) procurement arrangements on farmers’ incentives to invest in cattle quality.

The research methods involve a conceptual model based on principal-agent framework and data from targeted interviews of cattle farmers and slaughterhouse managers in the Western Region of São Paulo state of Brazil.

Findings highlight the potential for adverse selection of low-quality cattle producers under LW arrangement and misaligned incentives for quality improvement, they also illustrate incentive compatibility of DW arrangement when the carcass yield is verifiable by producers. The evidence from field data was largely consistent with the predictions of the model and highlighted the important role of trust for a lasting procurement relationship under DW arrangement.

Due to the lack of publicly available data and the challenges associated with the collection of primary field data, the sample is limited to 30 cattle producers and 5 processing firms.

This paper provides a theoretical and empirical platform for developing further research on coordination at the producer–processor interface of beef supply chain in Brazil and other countries with similar transaction characteristics. The findings will assist in designing more incentive compatible and self-enforcing arrangements between cattle farmers and slaughterhouses to enhance the product quality and the overall efficiency of the supply chain.

Target cost contracts are commonly used to share the monetary outcome of work or a project. However, discussion is ongoing, as to what constitutes optimal sharing. The purpose of this paper is to examine optimal sharing and derives a result for defined risk assumptions on the owner (risk neutral) and contractor (risk-averse ranging to risk neutral).

The derivation is based on solving a constrained maximization problem using ideas from principal-agent theory. Practitioners were engaged in a designed exercise in order to validate the approach and propositions. The influence of the contractor's level of risk aversion, the cost uncertainty and the contractor's effort effectiveness are examined.

The paper shows that, at the optimum, the sharing ratio between contractor and owner needs to reduce and the fixed fee needs to increase when the contractor becomes more risk-averse, the level of the cost uncertainty increases, or the effectiveness of the contractor effort decreases.

The paper's findings provide practitioners with a useful benchmark for outcome sharing in target contracts.

Existing work on outcome sharing in target contracts is limited to being qualitative and anecdotal in nature. This paper extends existing knowledge by providing a quantitative treatment of optimal sharing.

This chapter proposes a survey of the main results produced by the literature on licensing and some original insights, with a particular focus on globalization, North–South models of technology transfer, the issue of how the intellectual property rights influences international licensing, and asymmetric information.