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In this paper, the influence of cutting regimes on surface texture and productivity of cylinder liner is shown, obtained by normal honing. Furthermore, normal honing power and torque is discussed. The paper aims to discuss these issues.

Normal honing was done on grey cast iron cylinder liners. Both pre- and finishing honing were done by mechanical means, to achieve the required level of surface texture quality, traditionally achieved by a combination of electrochemical pre-honing and mechanical finishing honing. To determine the most influential parameter on normal honing, statistical mathematical model was devised. Surface texture was controlled by light microscope and scanning electron microscope.

Mathematical model describing the influence of cutting speed, feed rate and depth of cut has shown that the most influential parameter on maximum peak height, productivity and specific volume productivity was shown. The most influential parameter has shown to be cutting speed.

There are two practical implications of this work: this work is a further contribution of understanding normal honing and the influence of various parameters on the quality of normal honing, both in view of surface texture and productivity, as the main drawback of this method. This work offers useful information for honing system designers, as torque and power of normal honing are given.

Two main achievements are given in this paper: as the main drawback of normal honing is lower productivity, the optimization of honing parameters may to some extent resolve this problem. Lower productivity is the result of lower cutting speeds and pressures, which in turn, give normal honed surface a higher quality compared to plateau honing. Lower power and torque demand a lower energy demands, as well as a less complex honing machine which may lead to further savings.

The purpose of this paper is to explore the influence of tool kinematics parameters on surface roughness, productivity and cutting angle for grey cast iron cylinder liners machined by normal honing.

For experimental investigation, a long stroke honing system was used. Diamond and SiC tools were used, for pre‐ and finishing, respectively. The values of cutting parameters were varied within the following limits: cutting speed v_s=0.931‐1.11 m/s; specific pressure of pre‐honing process p_d=1.0‐1.4 N/mm² and specific pressure of finishing honing process p_z=0.2‐0.5 N/mm². The analysis of dispersion was conducted for determining the mathematical model for cutting parameter influence on surface roughness and productivity.

Dispersion analysis proved that the most influential parameters on maximum roughness depth are cutting speed for D181 tool and specific pressure of finishing honing for D151 tool. The most influential parameter on productivity in the honing process with D181 and D151 tool is cutting speed.

The paper gives new information related to the normal honing optimization process. Normal honing offers the highest surface quality which is achieved by a low speed machining. However, that means also a relatively low productivity, demanding a thorough process optimization. Furthermore, normal honing is usually done by ECH pre‐honing and mechanical finishing honing, but in this paper, all‐mechanical honing was used for the same result, at a lower lost.

The purpose of this paper is to present a novel approach on investigating critical current densities in the solder joints of chip-size surface mounted device (SMD) components. The investigation involves a numerical approach and a physical validation with selected track-to-pad connections and high current loads (CXs).

During the investigations, shape of solder fillets was calculated in Surface Evolver, and then the current densities were calculated accordingly in the given geometry. For the verification, CX tests were performed on joints at elevated temperatures. The joints were qualified with X-ray microscopy, cross-section analysis and shear tests.

This study ascertained that the inhomogeneity in current density depends on the track-to-pad structure of the joint. Also this study found that the heavy CX decreases the mechanical strength, but the degradation does not reach the level of electromigration (EM)-induced voiding.

The heavy CX significantly affects joint reliability and the results point out to EM-induced failure-limitations on printed circuit board (PCB)-based assemblies due to the thermomechanical weakness of the FR4 material.

The experiments investigate current density from a novel aspect on more frequently used small-scale components with different track-to-pad configurations – pointing out possible failure sources.

Decision-making structures are commonly associated with the logistics challenges experienced during disaster operations. However, the alignment between the operational level and the decision-making structure is commonly overlooked. The purpose of this paper is to provide an analysis of the fit of both levels and its impact on performance.

The research is developed around a case study in Mexico. Through a review of the disaster management policy in the country, interviews and secondary data, the paper provides an analysis of the current decision-making structure, the logistics activities undertaken by authorities and the impact of the alignment between both components on logistics performance.

The analysis suggests that several of the challenges commonly associated with centralisation are actually rooted on its alignment with the operational level. The logistics performance is negatively affected by faulty assumptions, poorly planned procedures, inconsistent decision-making and poorly designed structures. The case showed the need to align the operational level with a centralised perspective to increase responsiveness, flexibility and the interaction between different organisations.

This paper identifies the impact of the misalignment between the decision-making structure and the operational level on logistics performance, an area currently understudied. It moves from the current argument about the appropriate decision-making structure for disaster management to the identification of components to implement an efficient and effective disaster management system. Additionally, this paper provides recommendations for best practices in humanitarian logistics, which are applicable to Mexico and other countries using a centralised decision-making approach.

The purpose of this paper is to explore the implications of natural resource scarcity (NRS) for companies’ supply chain strategies.

Drawing on the resource dependence theory (RDT), a conceptual model is developed and validated through the means of exploratory research. The empirical work includes the assessment of qualitative data collected via 22 interviews representing six large multinational companies from the manufacturing sector.

When the resources are scarce and vitally important, companies use buffering strategies. Buffering and bridging strategies are preferred when there are a few alternative suppliers for the specific resource and when there is limited access to scarce natural resources.

The research focuses on large multinational manufacturing companies so results may not be generalised to other sectors and to small- and medium-sized firms. Future research needs to examine the implications of NRS for organisational performance.

This research provides direction to manufacturing companies for adopting the best supply chain strategy to cope with NRS.

This paper adds to the body of knowledge by providing new data and empirical insights into the issue of NRS in supply chains. The RDT has not been previously employed in this context. Past studies are mainly conceptual and, thus, the value of this paper comes from using a qualitative approach on gaining in-depth insights into supply chain-related NRS strategies and its antecedents.

The objective of this research was to develop a new and highly accurate approach based on a fuzzy inference system (FIS) for the evaluation of usability based on ISO 9241-210:2019. In this study, a fully automated method of usability evaluation is used for interactive systems with a special look at interactive social robots.

Fuzzy logic uses as an intelligent computing technique to deal with uncertainty and incomplete data. Here this system is implemented using MATLAB fuzzy toolbox. This system attempted to quantify four criteria that correlate highly with ISO 9241-210:2019 criteria for the evaluation of interactive systems with maximum usability. Also, the system was evaluated with standard cases of computer interactive systems usability evaluation. The system did not need to train various data and to check the rules. Just small data were used to fine-tune the fuzzy sets. The results were compared against experimental usability evaluation with the statistical analysis.

It is found that there was a high strong linear relation between the FIS usability assessment and System Usability Scale (SUS) based usability assessment, and authors’ new method provides reliable results in the estimation of the usability.

In human-robot systems, human performance plays an important role in the performance of social interactive systems. In the present study, the proposed system has considered all the necessary criteria for designing an interactive system with a high level of user because it is based on ISO 9241-210:2019.

For future research, the system could be expanded with the training of historical data and the production of rules through integrating FIS and neural networks.

This system considered all essential criteria for designing an interactive system with a high level of usability because it is based on ISO 9241-210:2019. For future research, the system could be expanded with the training of historical data and the production of rules through integrating FIS and neural networks.

The space fractional PDEs (SFPDEs) play an important role in the fractional calculus field. Proposing a high-order, stable and flexible numerical procedure for solving SFPDEs is the main aim of most researchers. This paper devotes to developing a novel spectral algorithm to solve the FitzHugh–Nagumo models with space fractional derivatives.

The fractional derivative is defined based upon the Riesz derivative. First, a second-order finite difference formulation is used to approximate the time derivative. Then, the Jacobi spectral collocation method is employed to discrete the spatial variables. On the other hand, authors assume that the approximate solution is a linear combination of special polynomials which are obtained from the Jacobi polynomials, and also there exists Riesz fractional derivative based on the Jacobi polynomials. Also, a reduced order plan, such as proper orthogonal decomposition (POD) method, has been utilized.

A fast high-order numerical method to decrease the elapsed CPU time has been constructed for solving systems of space fractional PDEs.

The spectral collocation method is combined with the POD idea to solve the system of space-fractional PDEs. The numerical results are acceptable and efficient for the main mathematical model.