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In a conventional finite element analysis, material properties, dimensions and applied loads are usually defined as deterministic quantities. This simplifying assumption however, is not true in practical applications. Using statistics in engineering problems enables us to consider the effects of the input variables dispersion on the output parameters in an analysis. This provides a powerful tool for better decision making for more reliable design. In this paper, a probabilistic based design is presented which evaluates the sensitivity of a mechanical model to random input variables. To illustrate the effectiveness of this method, a simple bracket is analyzed for stress‐strain behavior using commercially available finite element software. Young’s modulus, applied pressure and dimensions are considered as random variables with Gaussian distribution and their effects on maximum stress and displacement is evaluated. The finite element results are compared with reliability based theoretical results which show very good agreement. This demonstrates the capability of commercially available software to handle probabilistic approach design.

Contact problems are central to solid mechanics as contact is the principal method of applying loads to a deformable body and the point with resulting stress concentration is often the most critical point within the body. This paper presents a finite element model for the elastic contact between two cylinders at several positions. The effects of friction and surface roughness have been considered. The contact between two skew cylinders is also investigated. Results from finite element model show a good agreement with those of analytical solutions available in the literature. It was seen that the geometry of contacting bodies and orientation of applied load effect highly on contact stresses. Although the effect of surface roughness was seen to be more than that of friction, both of them can be assumed negligible in elastic contact problems.

The purpose of this paper is to show how a system of differential equations of one‐dimensional transient cooling heat conduction of different multi‐layer slabs has been solved numerically. A simple deterministic filtering matrix has been developed to remove errors involved in the experimental temperature measurements.

The system of differential equations is solved through Crank‐Nicolson method using a developed computer code. The developed matrix is based on the available information about the system and is strong enough to detect and remove errors from the measured temperatures.

The filtering algorithm is very straightforward and easy to implement and needs to be developed once for a given system.

This paper shows how the governing equations of transient heat conduction of multi‐layer slabs have been solved through Crank‐Nicolson method using a developed computer code. The code is user friendly and solves a large system of simultaneous differential equations for any given composite slab configurations. Furthermore, a matrix filter has been suggested to remove experimental errors. The filter is based on the available information about the considered system. The developed matrix filter is shown to be a powerful technique to detect the noisy data and correct them while intelligent enough not to harm good data. The filtering algorithm is very straightforward and easy to implement and needs to be developed once for a given system.

The purpose of this paper is to investigate steady state creep behavior of a functionally graded rotating disc under varying thermal gradient (TG).

The steady state creep in a rotating FGM disc with linearly varying thickness has been investigated by using von-Mises yield criterion. The disc under investigation is assumed to be made of FGM containing non-linear distribution of silicon carbide particle (SiC_p) in a matrix of pure aluminum along the radial distance. The creep behavior of the FGM composite disc is described by threshold stress-based law. The stresses and strain rates in the FGM disc have been estimated for different kinds of TG.

The results indicate that when the FGM disc is subjected to a radial TG, with temperature increasing with increasing radius, the radial stress in the disc increases over the entire disc but the tangential and effective stresses increase near the inner radius and decrease toward the outer radius. The imposition of such a radial TG in the FGM disc leads to significant reduction in the radial and tangential strain rates. With the increase in magnitude of TG in the FGM disc, the inhomogeneity in creep stresses increases but the inhomogeneity in strain rates decreases significantly, thereby reducing the chances of distortion in the FGM disc.

The creep strain rates in rotating FGM disc could be significantly reduced when the disc is subjected to a radial TG, with temperature increasing with increasing radius.

Aerospace industry was pioneered in the use of superplastic forming (SPF) process. Weight saving is the most important need in this industry. For this reason, there is special attention paid to this method. Blow forming is a common method for SPF process. Process parameters such as temperature and pressure have significant effects on part accuracy, quality and desired characteristics. The purpose of this paper is to present a numerical and experimental investigation of process parameters in superplastic free bulge forming.

In this paper, superplastic free bulge forming of Al‐5083 has been studied. First, free bulge tests have been done at two different pressures. Bulge height variations were recorded for different pressure and temperature. The forming time was determined according to the forming pressure and temperature. Then, simulation of free bulge process has been carried out using creep behavior model at high temperature. Bulge height and thickness distribution are obtained at two different pressure settings. These results have been compared with experimental results presenting a good agreement. Also the effects of temperatures and pressure on the required process time are compared for a certain bulge height. Finally, thickness distribution profile for different temperatures, pressures and initial thicknesses have been studied.

A numerical and experimental investigation has been presented that can be used to study the process parameters. These findings show the effects of temperatures, pressure and initial thicknesses on sheet forming.

The results of this work show that higher temperature and forming pressure will reduce the required process time for a certain bulge height. Reduction of these parameters can improve thickness distribution. Also, by considering the effects of both pressure and temperature, it is shown that using lower forming pressure at higher temperature is more suitable for forming. The findings of this work can provide more understanding of the process for aircraft part designers and manufacturing process planners.

The purpose of this paper is to determine the current state of the Lean principles adopted by food small and medium-sized enterprises (SMEs).

The case study approach was undertaken in order to gain insights into Lean adoption. Nine Greek food SMEs certified according to the ISO 9001 quality management system (QMS) and the ISO 22000 food safety management system (FSMS) were approached. Interviews were conducted with the chief executive officers and the company managers in charge of the QMS or FSMS, based on a structured questionnaire.

The food SMEs participating in the present study adopt Lean principles to a high extent. However, there is room for further improvement.

The fact that the data collected suggests subjective business evidence and not objective as well as the fact that only two representatives of each of the nine food SMEs were conducted, comprise the main limitations of the present study. So, the results should be considered with caution, as far as the Lean adoption in the Greek food sector is concerned. Based on these limitations, future research suggestions can be made.

Based on the present study, suggestions can be made regarding the successful adoption of Lean principles, not only for the sample SMEs but also for the whole of the food sector. More specifically, by determining the strengths and weaknesses of the food SMEs’ efforts to adopt Lean, suitable managerial initiatives can be undertaken by these companies as well as the whole sector to fully adopt Lean and derive the respective benefits.

The paper provides insights into the adoption of Lean principles in the Greek food sector. This is the first study in the field of Lean that has been carried out in the Greek food SMEs.

The purpose of this paper is to investigate a subject accounting firm’s existing workflow processes for preparing individual tax returns with an emphasis on identifying predominant areas of waste.

Specific Quality and Lean tools were applied to qualitative data secured from on-site visits to the firm. Quantitative data analysis of productivity measures was performed to identify additional sources of muda (waste) as well as validate the findings from the qualitative analysis. Corrective actions were recommended as applicable.

This case study of the subject firm identifies predominant wastes in the individual tax return process as defects and waiting. The authors propose that these categories of waste (waiting and defect) may indeed be the predominant forms of waste in service organizations and require further research.

At least two limitations exist. The first was the inability to capture exact cycle times for each of the process steps. A second limitation was that the data on staff performance were gathered via interview rather than through direct observation.

Individual income tax return preparation (Form 1040) provides a significant revenue stream for many accounting firms. Managing the processes involved in an effective and timely fashion is critical to profitability. Additionally, other service industries, including financial and accounting firms of similar size or function, may find these areas of waste relevant and adopt similar strategies for eliminating or reducing them in service-processes.

Negligible literature exists concerning wastes in accounting firms. However, accounting firms in the USA earn an average of more than 50 percent of their total fees from tax services, including income tax return preparation.

This paper aims to review and critique the public sector knowledge management (KM) literature, offers an overview of the state of public sector KM research and outlines a future research agenda.

Articles published in KM journals are analyzed using a structured literature review methodology. The paper analyzes 180 papers published within ten journals specializing in the field of KM.

Public sector KM is a research area of growing importance. Findings show that few authors specialize in the field and there are several obstacles to developing a cohesive body of literature. Low levels of international cooperation among authors and international comparisons mean that the literature is fragmented. Some research topics and some geographical areas within the public sector theme are over-analyzed, while others are under-investigated. Additionally, academic researchers should re-think their methodological approach if they wish to make significant contributions to the literature and work toward developing research which impacts practice in conjunction with practitioners.

The paper presents a comprehensive structured literature review of the articles published in KM journals. The paper’s findings can offer insights into future research needs.

As the COVID-19 epidemic ravages the world in the fourth industrial revolution era, the manufacturing sector faces its worst situation in a century. Lean philosophy, renowned as a “warrior philosophy,” can be an able rescuer to these industries. This study aims to identify the hurdles to lean strategy implementation and conduct an analysis to provide cognizance to policymakers, practitioners and decision-makers.

This study aims to identify the obstacles that obstruct lean implementation into seven primary barriers/components, with the fuzzy DEMATEL approach being used to evaluate the critical factors as well as the cause and effect factors among them. Expert opinions are sought to obtain the relevant data for evaluation purposes.

The results reveal that a firm should focus on firm cultural conflict scenario, resources–responses incapability, improve on suppliers’ attitude and execute a proper planning and logistics equation to alleviate the hindrances of implementing lean. As these causal factors influence the effect factors, namely, top management vision, management–employee relationship and human resource building, focusing on them automatically improves the effect factors; thus, the surge to overcome resistance to lean implementation is alleviated.

This research aids in identifying and analyzing lean implementation issues in the manufacturing and industrial sectors. The observations, results and insights drawn can act as a guiding force to rupture the resistance envelope covering the domain of lean implementation and possibly reinstating industries to survive and excel in the business post-COVID era.

This research introduces barriers to lean implementation in a unique way, as it articulates all sections of an industry and group the barriers based on the classification. It further prioritizes the barriers for their importance in the Indian industrial scenario. This would help the industry professionals and managers access the barriers and generate insight on how and where to start implementing lean.