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Values of parameters such as temperature, humidity, number of plastic products and the location of plastic injection moulds are required to determine the efficiency of plastic injection moulds with a view to improving the quality of the outputs. This article determined the appropriate sensors for the measurement of these essential parameters in the most suitable form of representation of the data to aid a proficient analysis of the data.

The outputs of these sensors were obtained by connecting the sensors to the general-purpose input/output (GPIO) pins of a Raspberry Pi and writing a Python programme for the connected GPIO pins. The values of the outputs of these sensors were represented in a graphical form. The connection of the Raspberry Pi and the sensors were done with a full-sized breadboard and jumper wires. A computer-aided design (CAD) of the connections was produced using Fritzing software.

The appropriate sensors determined are MLX90614 infrared thermometer sensor, DHT11 humidity sensor, pixy2 vision sensor and Neo-6m GPS sensor. This study proposed that the sensors analytic system be applied on an industrial plastic injection mould to measure and display the various parameters of the injection moulds for the purpose of understanding and improving the performance of the injection mould

An electronic system that provides the continuous values of essential parameters of a plastic injection mould in operation.

This paper aims to identify critical factors that influence small and medium-sized enterprise (SME) suppliers’ involvement in their customers’ product development and contrast these with the factors identified from the customer perspective.

A multiple case study approach was used, including four companies. Data were collected through 32 semi-structured interviews, six workshops and documents.

A model is presented that merges this study’s nine identified critical factors with seven critical factors from the customer perspective. The model provides a dual perspective of supplier involvement in product development, wherein the supplier and customer perspectives are concurrently addressed. Some factors are unique for the supplier, but several mirror those on the customer side.

The study is based on data from SME suppliers in Northern Europe. As it is expected that SME companies are more constrained by limited resources, future studies could study critical factors at larger suppliers.

Customers and suppliers having insights about the critical factors can provide better conditions for product development for the other actor; for example, when evaluating customer–supplier integration.

The presented model of critical factors provides a more nuanced picture of supplier involvement in product development as prior research has been biased toward the customer perspective. This study emphasizes the importance of contextual information that has been unnoticed in the literature.

Honeycombs enjoy wide use in various engineering applications. The emergence of additive manufacturing (AM) as a method of customisable of parts has enabled the reinvention of the honeycomb structure. However, research on in-plane compressive performance of both classical and new types of honeycombs fabricated via AM is still ongoing. Several important findings have emerged over the past years, with significance for the AM community and a review is considered necessary and timely. This paper aims to review the in-plane compressive performance of AM honeycomb structures.

This paper provides a state-of-the-art review focussing on the in-plane compressive performance of AM honeycomb structures, covering both polymers and metals. Recently published studies, over the past six years, have been reviewed under the specific theme of in-plane compression properties.

The key factors influencing the AM honeycombs' in-plane compressive performance are identified, namely the geometrical features, such as topology shape, cell wall thickness, cell size and manufacturing parameters. Moreover, the techniques and configurations commonly used for geometry optimisation toward improving mechanical performance are discussed in detail. Current AM limitations applicable to AM honeycomb structures are identified and potential future directions are also discussed in this paper.

This work evaluates critically the primary results and findings from the published research literature associated with the in-plane compressive mechanical performance of AM honeycombs.

This study aims to identify how the personal social capital of opinion leaders contributes to the market adoption of start-up innovations.

A design-oriented case study is undertaken with a start-up company focusing on the development and commercialization of innovations in the veterinary market. Based on a literature review, the authors examine the social capital in value creation and the role of opinion leaders and use qualitative methodology and semi-structured in-depth interviews to collect data.

The adoption of innovations could start with opinion leaders that will later share their experience with other members of the professional community. In turn, social capital allows for creating a collaboration between start-ups and leaders based on a number of specific parameters.

This paper contributes to marketing literature by providing new insights regarding collaboration between start-ups and opinion leaders. The collaboration between opinion leaders and start-ups could be implemented not only in the veterinary industry but also in other industries with minor adaptations. Authors demonstrate how the social capital of external stakeholders may be used as a resource of the company for business development. The main contribution of this study is to demonstrate that social capital could be used as a parameter for the adoption of innovations. The key parameters that allow creating cooperation between start-up and opinion leader have been identified.

The purpose of this study is to develop a cylindrical capacitive sensor that has the advantages of high resolution, small size and designability and can be easily installed on lubricant pipeline to monitor lubricant oil debris.

A theoretical model of the cylindrical capacitive sensor is presented to analyze several parameters’ effectiveness on the performance of sensor. Numerical simulations are then conducted to determine the optimal parameters for preliminary experiments. Experiments are finally carried out to demonstrate the detectability of developed capacitive sensors.

It is clear from experimental results that the developed capacitive sensor can monitor the debris in lubricant oil well, and the capacitance values increase almost linearly when the number and size of debris increase.

There is lot of further work to do to apply the presented method into the application. Especially, it is necessary to consider several factors’ influence on monitoring results. These factors include the flow rate of the lubricant oil, the temperature, the debris distribution and the vibration. Moreover, future work should consider the influence of the oil degradation to the capacitance change and other contaminations (e.g. water and dust).

This work conducts a feasibility study on application of capacitive sensing principle for detecting debris in aero engine lubricant oil.

The novelty of the presented capacitance sensor can be summarized into two aspects. One is that the sensor structure is simple and characterized by two coaxial cylinders as electrodes, while conventional capacitive sensors are composed of two parallel plates as electrodes. The other is that sensing mechanism and physical model of the presented sensor is verified and validated by the simulation and experiment.

The paper aims to describe the process to obtain a complete municipal database from the 2011 Spanish Census information. By complete, the authors mean variables for the full sample of the 8,116 municipalities as of the census reference date. In addition, the database should be consistent with the public census information released by the National Statistical Institute: microdata and customized tables.

The authors use mainly small area demographic and synthetic estimators that are reconciled using biproportional adjustment (iterative proportional fitting), when needed.

As a result, the authors obtain a complete and consistent municipal database composing 55 variables related to socio-demographic characteristics of persons.

The provision of a complete and consistent municipal database, available for download, which is absent in the original 2011 Spanish Census.

How can joint open innovation (OI) projects between small and medium-sized enterprises (SMEs) and large companies (LCs) be effectively managed? This study aims to try to answer this research question with a focus on the critical success factors (CSFs) of such cooperation.

Based on 40 semi-structured interviews with Italian SMEs and LCs engaged in various industries, 20 open OI projects involving SMEs and LCs are investigated using a reflexive thematic analysis, a methodology involving both deductive and inductive approaches.

Fifteen CSFs grouped into seven categories emerge from the analysis of joint OI projects between SMEs and LCs. Among them, shared leadership, dynamic decision-making and priority setting emerge as essential elements at the basis of the proposed SMEs–LCs cooperation in joint OI projects that were not sufficiently addressed by prior studies.

To the best of the authors’ knowledge, this study is the first to provide an evidence-based framework for managing joint OI projects between SMEs and LCs. Relatedly, this study links the practices and most recurring CSFs that facilitate such cooperation.

Because of the anisotropy of the process and the variability in the quality of printed parts, finite element analysis is not directly applicable to recycled materials manufactured using fused filament fabrication. The purpose of this study is to investigate the numerical-experimental mechanical behavior modeling of the recycled polymer, that is, recyclable polyethylene terephthalate (rPET), manufactured by a deposition FFF process under compressive stresses for new sustainable designs.

In all, 42 test specimens were manufactured and analyzed according to the ASTM D695-15 standards. Eight numerical analyzes were performed on a real design manufactured with rPET using Young's compression modulus from the experimental tests. Finally, eight additional experimental tests under uniaxial compression loads were performed on the real sustainable design for validating its mechanical behavior versus computational numerical tests.

As a result of the experimental tests, rPET behaves linearly until it reaches the elastic limit, along each manufacturing axis. The results of this study confirmed the design's structural safety by the load scenario and operating boundary conditions. Experimental and numerical results show a difference of 0.001–0.024 mm, allowing for the rPET to be configured as isotropic in numerical simulation software without having to modify its material modeling equations.

The results obtained are of great help to industry, designers and researchers because they validate the use of recycled rPET for the ecological production of real-sustainable products using MEX technology under compressive stress and its configuration for numerical simulations. Major design companies are now using recycled plastic materials in their high-end designs.

Validation results have been presented on test specimens and real items, comparing experimental material configuration values with numerical results. Specifically, to the best of the authors’ knowledge, no industrial or scientific work has been conducted with rPET subjected to uniaxial compression loads for characterizing experimentally and numerically the material using these results for validating a real case of a sustainable industrial product.

This method will become a new development trend in subgrade structure design for high speed railways.

This paper summarizes the structural types and design methods of subgrade bed for high speed railways in China, Japan, France, Germany, the United States and other countries based on the study and analysis of existing literature and combined with the research results and practices of high speed railway subgrade engineering at home and abroad.

It is found that in foreign countries, the layered reinforced structure is generally adopted for the subgrade bed of high speed railways, and the unified double-layer or multi-layer structure is adopted for the surface layer of subgrade bed, while the simple structure is adopted in China; in foreign countries, different inspection parameters are adopted to evaluate the compaction state of fillers according to their respective understanding and practice, while in China, compaction coefficient, subsoil coefficient and dynamic deformation modulus are adopted for such evaluation; in foreign countries, the subgrade top deformation control method, the subgrade bottom deformation control method, the subsurface fill strength control method are mainly adopted in subgrade bed structure design of high speed railways, while in China, dynamic deformation control of subgrade surface and dynamic strain control of subgrade bed bottom layer is adopted in the design. However, the cumulative deformation of subgrade caused by train cyclic vibration load is not considered in the existing design methods.

This paper introduces a new subgrade structure design method based on whole-process dynamics analysis that meets subgrade functional requirements and is established on the basis of the existing research at home and abroad on prediction methods for cumulative deformation of subgrade soil.

Many additively manufactured parts suffer from reduced interlayer strength. This anisotropy is necessarily tied to the orientation during manufacture. When individual features on a part have conflicting optimal orientations, the part is unavoidably compromised. This paper aims to demonstrate a strategy in which conflicting features can be functionally separated into “co-parts” which are individually aligned in an optimal orientation, selectively reinforced with continuous fiber, printed simultaneously and, finally, assembled into a composite part with substantially improved performance.

Several candidate parts were selected for co-part decomposition. They were printed as standard fused filament fabrication plastic parts, parts reinforced with continuous fiber in one plane and co-part assemblies both with and without continuous fiber reinforcement (CFR). All parts were loaded until failure. Additionally, parts representative of common suboptimally oriented features (“unit tests”) were similarly printed and tested.

CFR delivered substantial improvement over unreinforced plastic-only parts in both standard parts and co-part assemblies, as expected. Reinforced parts held up to 2.5x the ultimate load of equivalent plastic-only parts. The co-part strategy delivered even greater improvement, particularly when also reinforced with continuous fiber. Plastic-only co-part assemblies held up to 3.2x the ultimate load of equivalent plastic only parts. Continuous fiber reinforced co-part assemblies held up to 6.4x the ultimate load of equivalent plastic-only parts. Additionally, the thought process behind general co-part design is explored and a vision of simulation-driven automated co-part implementation is discussed.

This technique is a novel way to overcome one of the most common challenges preventing the functional use of additively manufactured parts. It delivers compelling performance with continuous carbon fiber reinforcement in 3D printed parts. Further study could extend the technique to any anisotropic manufacturing method, additive or otherwise.