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The purpose of this study is to demonstrate and characterise a soft-tooled micro-injection moulding process through in-line measurements and surface metrology using a data-intensive approach.

A soft tool for a demonstrator product that mimics the main features of miniature components in medical devices and microsystem components has been designed and fabricated using material jetting technique. The soft tool was then integrated into a mould assembly on the micro-injection moulding machine, and mouldings were made. Sensor and data acquisition devices including thermal imaging and injection pressure sensing have been set up to collect data for each of the prototypes. Off-line dimensional characterisation of the parts and the soft tool have also been carried out to quantify the prototype quality and dimensional changes on the soft tool after the manufacturing cycles.

The data collection and analysis methods presented here enable the evaluation of the quality of the moulded parts in real-time from in-line measurements. Importantly, it is demonstrated that soft-tool surface temperature difference values can be used as reliable indicators for moulding quality. Reduction in the total volume of the soft-tool moulding cavity was detected and quantified up to 100 cycles. Data collected from in-line monitoring was also used for filling assessment of the soft-tool moulding cavity, providing about 90% accuracy in filling prediction with relatively modest sensors and monitoring technologies.

This work presents a data-intensive approach for the characterisation of soft-tooled micro-injection moulding processes for the first time. The overall results of this study show that the product-focussed data-rich approach presented here proved to be an essential and useful way of exploiting additive manufacturing technologies for soft-tooled rapid prototyping and new product introduction.

Open-access repositories (OARs) are essential for openly disseminating intellectual knowledge on the internet and providing free access to it. The current study aims to evaluate the growth and development of OARs in the field of technology by investigating several characteristics such as coverage, OA policies, software type, content type, yearly growth, repository type and geographic contribution.

The directory of OARs acts as the source for data harvesting, which provides a quality-assured list of OARs across the globe.

The study found that 125 nations contributed a total of 4,045 repositories in the field of research, with the USA leading the list with the most repositories. Maximum repositories were operated by institutions having multidisciplinary approaches. The DSpace and Eprints were the preferred software types for repositories. The preferred upload content by contributors was “research articles” and “electronic thesis and dissertations”.

The study is limited to the subject area technology as listed in OpenDOAR; therefore, the results may differ in other subject areas.

The work can benefit researchers across disciplines and, interested researchers can take this study as a base for evaluating online repositories. Moreover, policymakers and repository managers could also get benefitted from this study.

The study is the first of its kind, to the best of the authors’ knowledge, to investigate the repositories of subject technology in the open-access platform.

The purpose of this study is to clarify the mechanism of ambient and transient temperature effects on piezoelectric pressure sensors, and to propose corresponding compensation measures. The temperature of the explosion field has a significant influence on the piezoelectric sensor used to measure the shock wave pressure. For accurate shock wave pressure measurement, based on the actual piezoelectric pressure sensors used in the explosion field, the effects of ambient and transient temperatures on the sensor should be studied.

The compensation method of the ambient temperature is discussed according to the sensor size and material. The theoretical analysis method of the transient temperature is proposed. For the transient temperature conduction problem of the sensor, the finite element simulation method of structure-temperature coupling is used to solve the temperature distribution of the sensor and the change in the contact force on the quartz crystal surface under the step and triangle temperatures. The simulation results are highly consistent with the theory.

Based on the analysis results, a transient temperature control method is proposed, in which 0.5 mm thick lubricating silicone grease is applied to the sensor diaphragm, and 0.2 mm thick fiberglass cloth is wrapped around the sensor side. Simulation experiments are carried out to verify the feasibility of the control method, and the results show that the control method effectively suppresses the output of the thermal parasitic.

The above thermal protection methods can effectively improve the measurement accuracy of shock wave pressure and provide technical support for the evaluation of the power of explosion damage.

This study aims to adapt and validate the need satisfaction and frustration scale (NSFS) for the Brazilian gig work context and investigate the distinctiveness of the constructs of basic needs satisfaction and frustration among Brazilian gig workers.

Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted on a sample of 351 Brazilian gig workers.

Results from EFA supported a three-factor structure, while results from CFA psychometrically supported a six-factor correlated model. The items that constitute the NSFS presented good discriminant validity (heterotrait-monotrait ratio) and internal consistency (Cronbach’s alpha and McDonald’s omega coefficients). Results regarding criterion validity partially support previous empirical evidence that considers needs satisfaction and frustration independent in relation to well-being and ill-being while reinforcing the need for further investigations. The Brazilian version of the NSFS is shown to be an instrument with robust psychometric qualities to assess workers’ perception of basic needs satisfaction and frustration in Brazilian gig work context.

This study broadens the scope of research on basic psychological needs by introducing a valid and reliable instrument to assess workers’ perceptions of needs satisfaction and frustration in the Brazilian gig work context, a population that has been neglected in self-determination theory research.

O presente estudo teve como objetivos (1) adaptar e validar a Need Satisfaction and Frustration Scale para o contexto brasileiro de gig work e (2) investigar a distinção dos construtos de satisfação e frustração das necessidades básicas entre os trabalhadores gig brasileiros.

A análise fatorial exploratória (AFE) e a análise fatorial confirmatória (AFC) foram realizadas em uma amostra de 351 trabalhadores gig brasileiros.

Os resultados da EFA apoiaram uma estrutura de três fatores, enquanto os resultados da AFC apoiaram psicometricamente um modelo correlacionado de seis fatores. Os itens que constituem a NSFS apresentaram boa validade discriminante (razão heterotraço-monotraço) e consistência interna (coeficientes alfa de Cronbach e ômega de McDonald). Os resultados relativos à validade de critério apoiam parcialmente as evidências empíricas anteriores que consideram a satisfação e frustração das necessidades independentes em relação ao bem-estar e mal-estar, reforçando a necessidade de mais investigações. A versão brasileira da Need Satisfaction and Frustration Scale mostra-se um instrumento com qualidades psicométricas robustas para avaliar a percepção dos trabalhadores quanto à satisfação e frustração das necessidades básicas no contexto brasileiro de trabalho gig.

Este estudo amplia o escopo da pesquisa sobre necessidades psicológicas básicas ao introduzir um instrumento válido e confiável para avaliar as percepções de satisfação e frustração das necessidades dos trabalhadores no contexto brasileiro de gig work, uma população que tem sido negligenciada nas pesquisas da teoria da autodeterminação.

el presente estudio tuvo como objetivos (1) adaptar y validar la Escala de frustración y satisfacción de necesidades para el contexto del trabajo gig brasileño, y (2) investigar el carácter distintivo de los constructos de satisfacción y frustración de necesidades básicas entre los trabajadores gig brasileños.

se realizaron análisis factoriales exploratorios (AFE) y análisis factoriales confirmatorios (CFA) en una muestra de 351 trabajadores gig brasileños.

los resultados de EFA respaldaron una estructura de tres factores, mientras que los resultados de CFA respaldaron psicométricamente un modelo correlacionado de seis factores. Los ítems que componen la NSFS presentaron buena validez discriminante (relación heterorrasgo-monorrasgo) y consistencia interna (coeficientes alfa de Cronbach y omega de McDonald). Los resultados con respecto a la validez de criterio apoyan parcialmente la evidencia empírica previa que considera la satisfacción y la frustración de necesidades independientes en relación con el bienestar y el malestar, al tiempo que refuerzan la necesidad de más investigaciones. La versión brasileña de la Escala de Satisfacción de Necesidades y Frustración se muestra como un instrumento con sólidas cualidades psicométricas para evaluar la percepción de los trabajadores sobre la satisfacción de las necesidades básicas y la frustración en el contexto del trabajo gig brasileño.

este estudio amplía el alcance de la investigación sobre las necesidades psicológicas básicas al presentar un instrumento válido y confiable para evaluar las percepciones de los trabajadores sobre la satisfacción y la frustración de las necesidades en el contexto del trabajo gig brasileño, una población que ha sido descuidada en la investigación de teoría de la autodeterminación.

This study aims to elucidate the machining properties of low-cost expanded clay-reinforced syntactic foams by using different neural network models for the first time in the literature. The main goal of this endeavor is to create a casting machining-neural network modeling flow-line for real-time foam manufacturing in the industry.

Samples were manufactured via an industry-based die-casting technology. For the slot milling tests performed with different cutting speeds, depth of cut and lubrication conditions, a 3-axis computer numerical control (CNC) machine was used and the force data were collected through a digital dynamometer. These signals were used as input parameters in neural network modelings.

Among the algorithms, the scaled-conjugated-gradient (SCG) methodology was the weakest average results, whereas the Levenberg–Marquard (LM) approach was highly successful in foreseeing the cutting forces. As for the input variables, an increase in the depth of cut entailed the cutting forces, and this circumstance was more obvious at the higher cutting speeds.

The effect of milling parameters on the cutting forces of low-cost clay-filled metallic syntactics was examined, and the correct detection of these impacts is considerably prominent in this paper. On the other side, tool life and wear analyses can be studied in future investigations.

It was indicated that the milling forces of the clay-added AA7075 syntactic foams, depending on the cutting parameters, can be anticipated through artificial neural network modeling.

It is hoped that analyzing the influence of the cutting parameters using neural network models on the slot milling forces of metallic syntactic foams (MSFs) will be notably useful for research and development (R&D) researchers and design engineers.

This work is the first investigation that focuses on the estimation of slot milling forces of the expanded clay-added AA7075 syntactic foams by using different artificial neural network modeling approaches.

Owing to business uncertainty, it is prudent for organizations to rely on temporary employees to achieve numerical flexibility. This paper investigates the effect of perceived investment in temporary employee development (PITED) on organizational performance (OP) through the mediation process of organizational identification (OI), work engagement (WE) and the moderation process of perceived human resource policies (PHRP). A conceptual framework was built on social exchange theory and job demands-resource theory.

Data was collected from skilled temporary employees deputed at client organizations in the information technology business process management (IT-BPM) industry. Analysis was done using the partial least squares-structural equation modelling (PLS-SEM) method using SmartPLS 3.0 software.

The study established a significant association between PITED, OI and OP, in which OI acts as a partial mediator. In contrast, the mediating relationship of WE between PITED and OP was insignificant. PHRP moderated the relationship between PITED and OP.

This research suggests to top management and human resource leaders that PITED makes temporary employees identify with client organizations, resulting in increased OP.

This research builds on theoretical assumptions to adopt a temporary employee perspective on organizational initiatives and performance in the IT-BPM industry, which is uncommon.