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The purpose of this paper is to measure and compare the technical efficiency of construction companies in seven European countries: Austria, Germany, Hungary, Italy, Poland, Portugal and Spain, during the 2008–2015 period. The analysis involves nine sectors grouped into three divisions: construction of buildings (F41), civil engineering (F42) and specialized construction activities (F43), by NACE classification.

Multidirectional efficiency analysis was adopted to investigate the levels of efficiencies, the differences in those levels and the possible causes of such differences by further defining two new indices.

It showed that F43 is the most efficient division during the study period, followed by F42 and F41. The sectors/countries with less efficiency are: construction of roads and railways/Poland, construction of other civil engineering projects/Hungary, demolition and site preparation/Poland, other specialized construction activities/Portugal. Globally, the development of building projects sector uses resources in the most inefficient way and there was a drop in the efficiency in 2011 and 2013, showing a delay in the crisis impact. After 2010, civil engineering projects required a substantial effort to access resources. Other features regarding (in)efficiency were further identified.

The analysis was conducted with one of the most effective techniques in frontier analysis. The first introduced index allows for comparing efficient/inefficient subgroups, and the other index measures the resource acquisition effort, allowing a better comparison along years. The study provides a good understanding of the performance of the construction industry and indirectly exposes the strategies to overcome the crisis, through the identification of the inputs/outputs which are well/badly used.

The purpose of this paper is to investigate the effects of aging, pre‐conditioning, and build orientation on the mechanical properties of test samples fabricated using stereolithography (SL) and a commercially available resin.

American Society for Testing and Materials (ASTM) Standard D638 Type I specimens were manufactured in a Viper si2 SL system using WaterShed™ 11120 resin. The specimens were manufactured in two different build setups, designed to fit batches of 18 or 24 specimens with different build orientations. The specimens were randomly tested in tension, and a design of experiments (DOE) was used to determine the effect of aging (4, 30 or 120 days), pre‐conditioning (ambient, desiccant, or ASTM recommended conditioning), and build orientation (flat, on an edge, or vertical) on the ultimate tensile stress (UTS) and elastic modulus (E) of SL fabricated samples. Additionally, the fractured samples were imaged using scanning electron microscopy (SEM) to characterize the fractured surfaces.

Results showed that aging, pre‐conditioning, and build orientation each had an effect on the mechanical properties of the SL samples. In general, the samples aged at the shortest time frame (4 days) and the samples preconditioned according to ASTM recommendations had the lowest values of UTS. Regarding the effect of build orientation, the specimens built flat (with layers oriented along the thickness of the sample) had the lowest UTS and E values and the mechanical properties were statistically different from those built vertically or on an edge. The specimens built in the vertical orientation (with layers oriented along the length of the sample) had the highest values of UTS and E, yet the mechanical properties of the samples built on an edge (with layers oriented along the width of the sample) were not statistically different from the samples built vertically. SEM images of the fractured specimens showed fracture surfaces typical of polymers with a mirror zone and changes in surface texture from smooth to coarse.

The research was limited to a single commercially available resin. Through a statistical DOE approach, statistically significant differences in mechanical properties of SL fabricated samples were found as functions of aging, pre‐conditioning, and build orientation. These results can assist the ASTM F42 Committee with developing test standards specific to SL and the additive manufacturing community.

The statistical analyses presented here can help identify and classify the effects of fabrication, storage, and conditioning parameters on mechanical properties for SL fabricated parts. Understanding how the mechanical properties of SL resins are affected by different parameters can help improve the use of SL for a variety of applications including direct manufacturing of end‐use products.

In the optimisation of processing parameters for additive manufactured parts using, e.g. selective laser melting (SLM) or electron beam melting, the measurement of the part densities is essential and of high interest. However, there is no common standard. Different institutes and system providers are using their own principles and guidelines. This study investigates the accuracies of the three measurement principles: Archimedes method, microscopic analysis of cross sections and X‐ray scanning.

A total of 15 test samples on five density levels (densities between 90 and 99.5 per cent) were produced using the SLM process. The samples are analysed regarding the accuracy of the measurement principles and their reproducibility taking into account influencing parameters like the buoyancy of a sample in air (Archimedes method) or different magnifications of a cross section.

The Archimedes method shows a very high accuracy (±0.08 per cent for high densities) and repeatability (±<0.1 per cent) on all density levels. In contrast to the Archimedes method, taking a micrograph of a specific cross section allows to influence the resulting density and the coefficient of variation reaches values>4 per cent. However, for low porosities, mean densities are comparable to the results of the Archimedes method even though calculated densities are typically somewhat too high. The advantage of the image guided analysis (2D and 3D) is getting more information about the distribution, size and form of pores in the part.

The findings do not only refer to metallic parts but generally to all parts having a specific porosity. The study is a contribution to the American Society for Testing and Materials initiative F42 “Additive Manufacturing Technology” and especially to the subcommittee “test methods”.

A recent study confirmed that the particle size distribution of a metallic powder material has a major influence on the density of a part produced by selective laser melting (SLM). Although it is possible to get high density values with different powder types, the processing parameters have to be adjusted accordingly, affecting the process productivity. However, the particle size distribution does not only affect the density but also the surface quality and the mechanical properties of the parts. The purpose of this paper is to investigate the effect of three different powder granulations on the resulting part density, surface quality and mechanical properties of the materials produced.

The scan surface quality and mechanical properties of three different particle size distributions and two layer thicknesses of 30 and 45 μm were compared. The scan velocities for the different powder types have been adjusted in order to guarantee a part density≥99.5 per cent.

By using an optimised powder material, a low surface roughness can be obtained. A subsequent blasting process can further improve the surface roughness for all powder materials used in this study, although this does not change the ranking of the powders with respect to the resulting surface quality. Furthermore, optimised powder granulations lead generally to improved mechanical properties.

The results of this study indicate that the particle size distribution influences the quality of AM metallic parts, produced by SLM. Therefore, it is recommended that any standardisation initiative like ASTM F42 should develop guidelines for powder materials for AM processes. Furthermore, during production, the granulation changes due to spatters. Appropriate quality systems have to be developed.

The paper clearly shows that the particle size distribution plays an important role regarding density, surface quality and resulting mechanical properties.

Additive manufacturing (AM) and building information modelling (BIM) are emerging trends for which it has been claimed that both increase both efficiency and productivity in the construction industry. This study aims to synthesise and aggregate the literature addressing BIM integration in the AM of concrete structures and to exploit the joint value creation potential.

This study firstly applies a mixed-review method to achieve mutual corroboration and interdependency between quantitative and qualitative research approaches. Bibliometric mapping is applied to identify, map and synthesise the relevant literature. Scoping review is used to examine the extent, gap, range and nature of the research activity. Afterward, a cross-situational analysis, the threats, opportunities, weaknesses and strengths² matrix, is proposed and applied to exploit the joint value creation potential of different aspects of AM and BIM.

The study reveals a substantial interest in this field. However, progress in terms of integration is slow compared to the rapid development in interest in the two trends individually. The literature discusses or conceptualises such integration at building-scale, while prototyping or proof-of-concept processes are only rarely used. The study identified 12 joint value creation potentials through the integration of BIM in AM for concrete structures, which can create value by enabling more optimised designs, automated construction processes and data analytics that can apply throughout the building life-cycle process.

The advancements of BIM integration in the AM of concrete structures are analysed and joint value creation potentials are proposed. The study proposes a cross-situation analysis that can be applied to structure joint value creation potentials from the multi-dimensional integration of different factors and topics, especially for emerging technologies.

The purpose of this research is to develop a new slicing scheme for the emerging cooperative three-dimensional (3D) printing platform that has multiple mobile 3D printers working together on one print job.

Because the traditional lay-based slicing scheme does not work for cooperative 3D printing, a chunk-based slicing scheme is proposed to split the print job into chunks so that different mobile printers can print different chunks simultaneously without interfering with each other.

A chunk-based slicer is developed for two mobile 3D printers to work together cooperatively. A simulator environment is developed to validate the developed slicer, which shows the chunk-based slicer working effectively, and demonstrates the promise of cooperative 3D printing.

For simplicity, this research only considered the case of two mobile 3D printers working together. Future research is needed for a slicing and scheduling scheme that can work with thousands of mobile 3D printers.

The research findings in this work demonstrate a new approach to 3D printing. By enabling multiple mobile 3D printers working together, the printing speed can be significantly increased and the printing capability (for multiple materials and multiple components) can be greatly enhanced.

The chunk-based slicing algorithm is critical to the success of cooperative 3D printing, which may enable an autonomous factory equipped with a swarm of autonomous mobile 3D printers and mobile robots for autonomous manufacturing and assembly.

This work presents a new approach to 3D printing. Instead of printing layer by layer, each mobile 3D printer will print one chunk at a time, which provides the much-needed scalability for 3D printing to print large-sized object and increase the printing speed. The chunk-based approach keeps the 3D printing local and avoids the large temperature gradient and associated internal stress as the size of the print increases.

Recently, blockchain technology (BT) has resolved healthcare data management challenges. It helps healthcare providers automate medical records and mining to aid in data sharing and making more accurate diagnoses. This paper attempts to identify the critical success factors (CSFs) for successfully implementing BT in healthcare.

The paper is methodologically structured in four phases. The first phase leads to identifying success factors by reviewing the extant literature. In the second phase, expert opinions were solicited to authenticate the critical success factors required to implement BT in the healthcare sector. Decision Making Trial and Evaluation Laboratory (DEMATEL) method was employed to find the cause-and-effect relationship among the third phase’s critical success factors. In phase 4, the authors resort to validating the final results and findings.

Based on the analysis, 21 CSFs were identified and grouped under six dimensions. After applying the DEMATEL technique, nine factors belong to the causal group, and the remaining 12 factors fall under the effect group. The top three influencing factors of blockchain technology implementation in the healthcare ecosystem are data transparency, track and traceability and government support, whereas; implementation cost was the least influential.

This study provides a roadmap and may facilitate healthcare professionals to overcome contemporary challenges with the help of BT.

The purpose of this paper is to develop a data system to assess failure probability in small to medium‐sized enterprise (SME) reorganization.

The data system is based on information from 83 reorganized Finnish SMEs. Information is divided into four types: pre‐filing non‐financial, pre‐filing financial, reorganization submission, and reorganization plan information. Partial least squares (PLS) analysis is used in data mining to factorize information for each type of information. Logistic regression analysis is applied to assess failure probability.

Useful data system can be developed on the basis of pre‐filing non‐financial information to support reorganization decision. Pre‐filing financial information only marginally improves quality of information. Submission and reorganization plan information improve quality in terms of fit but do not significantly improve classification accuracy.

The sample is small and should be expanded in further studies. The system is developed for Finnish reorganizing firms. It can be generalized to any similar reorganization process.

The data system is useful for managers, lending specialists, investors, reorganization lawyers, and judges. It warns a SME about reorganization failure before filing petition (passive use). It is also useful in developing successful reorganization plans (active use).

This paper builds an extensive data system for assessing reorganization failure risk. It makes use of many variables that have not been analyzed in reorganization studies earlier. It deals with SMEs that is rare in reorganization studies. The paper utilizes PLS in assessing failure probability. It includes new analytical results on PLS.

The purpose of this paper is to measure technical efficiencies, slacks and input/output targets for 50 large Indian pharmaceutical firms.

The data are collected from Prowess of Centre for Monitoring of Indian Economy for the financial year 2010-2011. This study uses data envelopment analysis approach, taking raw material, salaries and wages, advertisement and marketing and capital usage cost as input variables and net sales revenue as output variable.

The paper finds that out of 50 firms, nine firms were overall technical efficient while 19 firms pure technical efficient and thus defined the efficient frontier. The BCC model identified that the inefficiency is either due to inefficient managerial performance or scale utilization. Further, firms are classified as high, low and middle robust firms on the basis of peer count. The study also analysed the slacks which were found to be significant in regard of some inputs, especially advertisement and marketing. The targets setting results have shown that all the inputs have significant scope for reduction.

The empirical results are useful in assessing the relative efficiency of the large Indian drug and pharmaceutical industry (ID&P) firms. The managers and owners can take corrective actions to reduce the cost of operations by optimizing advertising and marketing cost, capital usage cost and salary and wages so as to improve their efficiency.

Unlike the previous studies on the efficiency of the ID&P industry, the paper have shown the significance of improvement in managerial performance and scale utilization. In addition to this, excess inputs used in the production process and also possible target values of inputs and outputs are shown in the study. The robustness and stability of efficiency scores is also checked.