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One major problem preventing further application and benefits from additive manufacturing (AM) nowadays is that AM build parts always end up with poor geometrical quality. To help improving geometrical quality for AM, this study aims to propose geometrical deviation identification and prediction method for AM, which could be used for identifying the factors, forms and values of geometrical deviation of AM parts.

This paper applied the skin model-based modal decomposition approach to describe the geometrical deviations of AM and decompose them into different defect modes. On that basis, the approach to propose and extend defect modes was developed. Identification and prediction of the geometrical deviations were then carried out with this method. Finally, a case study with cylinders manufactured by fused deposition modeling was introduced. Two coordinate measuring machine (CMM) machines with different measure methods were used to verify the effectiveness of the methods and modes proposed.

The case study results with two different CMM machines are very close, which shows that the method and modes proposed by this paper are very effective. Also, the results indicate that the main geometrical defects are caused by the shrinkage and machine inaccuracy-induced errors which have not been studied enough.

This work could be used for identifying and predicting the forms and values of AM geometrical deviation, which could help realize the improvement of AM part geometrical quality in design phase more purposefully.

The purpose of this paper is to investigate the numerical fluid-structure interaction (FSI) framework for the simulations of mechanical behavior of new vortex generators (VGs) in smooth wavy fin-and-elliptical tube (SWFET) heat exchanger using the ANSYS MFX Multi-field® solver.

A three-dimensional FSI approach is proposed in this paper to provide better understanding of the performance of the VG structures in SWFET heat exchangers associated with the alloy material properties and geometric factors. The Reynolds-averaged Navier-Stokes equations with shear stress transport turbulence model are applied for modeling of the turbulent flow in SWFET heat exchanger and the linear elastic Cauchy-Navier model is solved for the structural von Mises stress and elastic strain analysis in the VGs region.

Parametric studies conducted in the course of this research successfully identified illustrate that the maximum magnitude of von Mises stress and elastic strain occurs at the root of the VGs and depends on geometrical parameters and material types. These results reveal that the titanium alloy VGs shows a slightly higher strength and lower elastic strain compared to the aluminum alloy VGs.

This paper is one of the first in the literature that provides original information mechanical behavior of a SWFET heat exchanger model with new VGs in the field of FSI coupling technique.

To evaluate assumptions relevance of an analytical heat flow model used in indirect measurement of heat capacity and thermal conductivity by the modulated calorimetry technique.

Assumptions are tested by comparing analytical prediction to numerical simulation results.

This study validates the analytical model for a solid sample.

This research only focuses on solid samples.

This paper allows a broader study on the relevance of modulated calorimetry on liquid samples.

The purpose of this paper is to study the thermal warpage of a plastic ball grid array (PBGA) mounted on a printed circuit board (PCB) during the reflow process.

A thermal-mechanical coupling method that used finite-element method software (ANSYS 13.1) was performed. Meanwhile, a shadow moiré apparatus (TherMoiré PS200) combined with a heating platform was used for the experimental measurement of the warpage of PBGA according to the JEDEC Standard.

The authors found that the temperature profiles taken from the simulated results and experimental measurement are consistent with each other, only with a little and acceptable difference in the maximum temperatures. Furthermore, the maximum warpage measurements during the reflow process are 0.157 mm and 0.149 mm for simulation and experimental measurements, respectively, with a small 5.37 per cent difference. The experimental measurement and simulated results are well correlated. Based on the validated finite element model, two factors, namely, the thickness and dimension of PCB, are explored about their effect on the thermal warpage of PBGA mounted on PCB during the reflow process.

The paper provides a thorough parametrical study of the thermal warpage of PBGA mounted on PCB during the reflow process.

The findings in this paper illustrate methods of warpage study by combination of thermal-mechanical finite element simulation and experimental measurement, which can provide good guidelines of the PCB design in the perspective of thermal warpage during the reflow process.

This paper aims to provide graduate students, researchers and government and independent agencies with an overview on BLEVE (i.e. boiling liquid expanding vapour explosion).

BLEVE has been studied by researchers, academicians, company specialists, and government and independent agencies. BLEVE incidents are collected from several sources such as technical and general articles, internet web sites and internal reports. BLEVE definitions, history, theory, types, hazards, and models are reviewed. BLEVE incidents are arranged and classified into fires, overfilling, explosions, overheating, runaways, overpressure, collisions, corrosion, and damage (derailment).

BLEVE types are classified into cold BLEVEs, hot BLEVEs, and BLEVEs. The major consequences of a BLEVE are thermal radiation from the resultant fireball and the fragments produced when the vessel fails. Several approaches are developed to describe BLEVE theory. BLEVE incidents are classified into explosions, damage (derailment), overfilling, fires, collisions, runaways, overpressure, overheating, and corrosion. The world has witnessed 74 BLEVE incidents in the period 1926‐1986. BLEVE incidents resulted in 1,427 fatalities and 635 injuries. The materials involved in BLEVE were flammable and non‐flammable. The highest frequencies of BLEVE incidents were due to explosions and damage to tanks. Explosion and damage BLEVE incidents resulted in high injuries. Overfilling and fire BLEVE incidents resulted in high fatalities.

This paper presents an overview of BLEVE definitions, history, incidents, types, theory, hazards and models. BLEVE incidents are classified. This paper combines scattered BLEVE incidents into one record.

The operations research method of data envelopment analysis (DEA) shows promise for assessing radiotherapy treatment plan quality. The purpose of this paper is to consider the technical requirements for using DEA for plan assessment.

In total, 41 prostate treatment plans were retrospectively analysed using the DEA method. The authors investigate the impact of DEA weight restrictions with reference to the ability to differentiate plan performance at a level of clinical significance. Patient geometry influences plan quality and the authors compare differing approaches for managing patient geometry within the DEA method.

The input-oriented DEA method is the method of choice when performing plan analysis using the key undesirable plan metrics as the DEA inputs. When considering multiple inputs, it is necessary to constrain the DEA input weights in order to identify potential plan improvements at a level of clinical significance. All tested approaches for the consideration of patient geometry yielded consistent results.

This work is based on prostate plans and individual recommendations would therefore need to be validated for other treatment sites. Notwithstanding, the method that requires both optimised DEA weights according to clinical significance and appropriate accounting for patient geometric factors is universally applicable.

DEA can potentially be used during treatment plan development to guide the planning process or alternatively used retrospectively for treatment plan quality audit.

DEA is independent of the planning system platform and therefore has the potential to be used for multi-institutional quality audit.

To the authors’ knowledge, this is the first published examination of the optimal approach in the use of DEA for radiotherapy treatment plan assessment.

Changes in economic markets have made it necessary to understand the psychology of individual investors. Conducting effective studies on the decision of investors to buy stock in the stock market can be useful. Therefore, it is necessary to identify and prioritize the factors affecting the decision-making of investors to purchase shares of the stock exchange. The purpose of this study was to analyze causal relationships and to weight effective factors on individual investment to purchase shares of Tehran Stock Exchange.

The present study is applied research in the term of its purposes and a descriptive-survey one in the term of data gathering methods. The data required in this study was collected through library and field studies. The study population included 35 investment experts. In present study, multi-criteria decision-making techniques in type-2 fuzzy environments have been used to analyze the causal relationships and weighing the factors affecting individual investment in purchasing stock in the stock market.

In the study, 4 indicators and 20 sub-indicators influencing individual investors’ decision to purchase shares of Tehran Stock Exchange were selected based on the literature review in the field of investment in the stock exchange, as well as interviews with experts. Analyzing the opinions of experts showed that they have much paid attention to financial index compare to the economic, political and psychological indicators of the market in determining the priority of indicators. In analyzing sub-indicators, it was identified that Iranian investors pay special attention to economic and political developments, political news and international economic developments.

The present study has been carried out in Iran, and therefore, is geographically limited to Iran. In thematic terms, it is limited to effective factors of individual investments in Tehran Stock Exchange. The statistical population of present study was limited to investing experts in Tehran Stock Exchange. The difference in financial, economic, social and political conditions of individuals was another limitation of present study. The main consequences of research were the explanation of causes of investors’ higher attention to financial factors than economic, political and mental factors of market in buying stocks.

Given the uncertainty in the market status, using multi-criteria decision-making techniques in financial analysis can help decision-makers to make better decisions. In addition, it would be possible to take into account many variables that do not have a mathematical aspect but are important in decision-making and lead to increased decision-making satisfaction. The research initially analyzed causal relationships of determinants of individual investment on stock exchange for buying stocks through a type-2 fuzzy approach.

The Analytic Hierarchy Process (AHP), as applied to the plant location problem, involves the structuring of this decision‐making process into different levels. Each level has certain attributes unique to the structure of the problem. Two levels of attributes are considered in the plant location problem. With respect to the first level, the user will focus upon all the tangible and intangible factors which affect the plant location problem, eventually leading to a stated objective or goal. Each attribute at this level will be assigned an appropriate weight through the AHP method. The second level of attributes consists of the possible locations under evaluation. The AHP method also assigns weights to each of the proposed locations as they relate to each of the attributes of the first level.

This paper investigates the interactional relationships between sustainable human resource management (SHRM) and organizational performance (OP). Sustainable HRM is an approach that links HRM and sustainability. These studies focused on integrating HR with sustainable developments, such as economic and social aspects, in favour of focusing on the environmental aspect. Organizational change is an ongoing process that has to be managed effectively to keep the change in place for a long time.

A framework was offered to estimate the cause-and-effect relation of the SHRM and OP factors. Data is gathered from professionals from various pharmaceutical industries. This study applied two methods, Fuzzy AHP and DEMATEL Type II. These techniques are used to understand the cause-and-effect factors and their interactions.

It was observed from the findings that the factor of SHRM, such as Social Justice (F2), Green Job Design (F5), Green Training (F6) and Implementation of Green Policy (F8), was the most critical for the pharmaceutical sector that effects Financial performance (F13), Customer Satisfaction (F15) and Market performance (F14). Pharmaceutical firms ought to coordinate public health advocacy efforts, engage in healthcare initiatives and provide financial support for environmentally friendly efforts that improve social and economic conditions.

For this sustainability, managers concentrate on creating an environment that is healthy and acceptable, and they work hard to mitigate the impact of natural factors and repair damage done to the environment; it is essential to move towards sustainable development to resolve environmental problems. Improving HR efficiency is among essential HRM responsibilities, as they expand the knowledge base of the workforce, enhance human capital, and eventually create valuable intangible assets and promote and encourage sustainable pharmaceutical products for some years.

This research paper has presented exclusive worth to the SHRM and organizational performance literature as it employs fuzzy FAHP and DEMATEL type 2. There is less research on SHRM in the pharmaceutical sector with these factors. In addition, FAHP and TYPE 2 DEMATEL are used in very few researches on SHRM approaches.