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With the problem of environment and energy becoming prominent, energy conservation and emission reduction have received more attention. In the using process, buildings not only have the inherent energy consumption but also have the energy consumption of equipment that is installed for improving the indoor environment. This study aims to investigate how to reduce the energy consumption of buildings through utilizing natural resources.

This paper briefly introduces three objective functions in the building energy-saving model: building energy consumption, natural lighting and natural ventilation. Genetic algorithm was used to optimize the building parameters to achieve energy conservation and comfort improvement. Then a two-story rental building was analyzed.

The genetic algorithm converged to Pareto optimal solution set after 10,000 times of iterations, which took 61024 s. The lowest energy consumption of the scheme that was selected from the 70 optimal solutions was 5580 W/(m²K), the lighting coefficient was 5.56% and Pressure Difference Pascal Hours (PDPH) was 6453 h; compared with the initial building parameters, the building energy consumption reduced by 3.40%, the lighting coefficient increased by 11.65% and PDPH increased by 9.54%.

In short, the genetic algorithm can effectively optimize the energy-saving parameters of buildings.

Within the growing study of transnational entrepreneurial practice, existing conceptualisation of diaspora entrepreneurship has often lacked engagement with the particularities of the diaspora condition. This paper seeks to advance theoretical understanding and empirical study of diaspora entrepreneurship through identifying the processes that generate diaspora entrepreneurship across economic, social and political spheres.

To analyse the relationship between the development of venture activity and diaspora (re)production, in depth, qualitative biographical analysis was undertaken with UK-based diaspora entrepreneurs embedded within the particular contexts of the Sri Lankan Tamil and Kurdish diasporas. Skilled and active diaspora entrepreneurs were purposively selected from these extreme case contexts to explore their entrepreneurial agency within and across the business, social and political realms.

Results identified key dimensions shaping the development of diaspora entrepreneurship. These comprised the role of diaspora context in shaping opportunity frameworks and the mobilisation of available resources, and how venture activity served to sustain collective diaspora identity and address diaspora interests. These findings are used to produce an analytical model of the generation of diaspora entrepreneurship to serve as a basis for discussing how heterogeneous and hybrid entrepreneurial strategies emerge from and shape the evolving diaspora context.

By placing the reproduction of social collectivity centre-stage, this paper identifies the particularities of diaspora entrepreneurship as a form of transnational entrepreneurship. This recognizes the significance of a contextualised understanding of entrepreneurial diversity within wider processes of diaspora development, which has important implications for policy and practice development in homeland and settlement areas.

Fused deposition modeling enables multiscale structure control. However, most of this structural space is unexplored. Specifically, the impact of biomimetic porous structures on the mechanical behavior and reliability of common thermoplastics are unclear. In this work, porous structures inspired by the multifunctional crab exoskeleton were 3D-printed with different raster orientations, including fully rotating rasters similar to Bouligand structures found in biological materials. Tensile tests and simulations were performed to observe the stochastic behavior of fracture properties and to reveal the underlying origins of mechanical reliability in biomimetic porous systems.

Tensile tests were performed on 3D-printed porous structures with four different rasters. These rasters were biomimetic Bouligand, semi-Bouligand, 00 raster and 45°/−45° raster. In addition, two different sets were manufactured to observe the impact of contours on the mechanical behavior. A total of 137 tensile tests were performed. A total of 88 finite element simulations were executed using Abaqus built-in Hashin damage initiation criterion and energy-based damage evolution law. Weibull analyses were performed to quantify the stochastic properties.

Biomimetic Bouligand structure is effective in increasing fracture strength. Average fracture strength of the Bouligand structure was 33% higher compared to the default 45°/−45° and 10% higher compared to 00 rasters. Variations in strength were lower in Bouligand structure compared to the default 45°/−45° raster. However, 00 raster had the highest Weibull modulus m = 54 compared to Bouligand m = 25 and 45°/−45° m = 17. Simulations showed that Bouligand structure is effective in increasing the mechanical reliability through local damage accumulation around the holes. The simulated Weibull modulus of the Bouligand structure was 40 compared to the moduli of other rasters that ranged from 18 to 25.

The mechanical reliability of porous Bouligand structures is higher compared to other rasters, which makes the biomimetic structure a better choice for industrial applications. Contours decrease the strength and strain at failure for 3D-printed porous structures. Bouligand structures with rotating raster orientations increased strength and strain at failure when contours are present in the porous structure.

To the best of the authors’ knowledge, this is the first study showing the effects of biomimetic raster orientations on the mechanical behavior and the effects of contours on the tensile fracture properties of 3D-printed porous acrylonitrile butadiene styrene using tensile tests and fracture simulations. This is the first study applying composite fracture model to anisotropic porous 3D-printed polymers.

The purpose of this paper is to investigate fast pyrolysis of maple fruit as an energy sources. This could serve as a solution to the energy sources problem.

Fast pyrolysis of maple fruit (samara) was achieved in a fixed bed reactor. The pyrolysis experiments have been conducted on the sample of maple seeds to particularly determine the effects of pyrolysis temperature, particle size and sweep gas flow rate on the pyrolysis product yields.

The oil of maple fruit from fast pyrolysis has good properties to be a potential candidate as a biofuel or as a source of chemicals. In addition to being environmentally desirable, it can reduce the energy cost, e.g. that Turkey imports a majority of its energy.

The use of maple fruit for fast pyrolysis and pyrolysis conditions impact on the yields of pyrolysis liquid can be considered as novel aspects of this paper.

Social media is a product that is co-created by consumers and multinational enterprises, that partially manage the customer experience and that has garnered significant attention in the field of international marketing. However, international marketing scholars have yet to address the societal costs of the use of social media, even as academics in other disciplines and business leaders are raising alarm that social media has created a digital ecosystem that may harm individuals within the global market. The objective of this research is to examine the generalizability of the relationship between the use of social media and the prevalence of depression across countries.

Employing social cohesion theory and the social network approach of the strength of ties, this work examines the relationship between the use of social media and time spent on social media at the country level and the prevalence of depression. The authors examine this issue within a 28-country, eight-year, unbalanced panel dataset, accounting for cultural, economic and structural factors.

The authors find that as more people within a country use social media, the prevalence of depression in that country increases. However, the authors also find that as the average time spent on social media in a country increases the deleterious relationship between the use of social media and the prevalence of depression diminishes.

Answering the calls in the international marketing literature for a greater understanding of the externalities (i.e. consumer well-being effects) of marketing activities of multinational companies, this study demonstrates the varying relationships of the use of and time spent on social media and the prevalence of depression at the population level, across a wide variety of countries, thus also contributing to the effort to improving generalizations from multi-country comparisons in international research.

There are many investigations in design methodologies, but there are also divergences and convergences as there are so many points of view. This study aims to evaluate to corroborate and deepen other researchers’ findings, dissipate divergences and provide directing to future work on the subject from a methodological and convergent perspective.

This study analyzes the previous reviews (about 15 reviews) and based on the consensus and the classifications provided by these authors, a significant sample of research is analyzed in the design for additive manufacturing (DFAM) theme (approximately 80 articles until June of 2017 and approximately 280–300 articles until February of 2019) through descriptive statistics, to corroborate and deepen the findings of other researchers.

Throughout this work, this paper found statistics indicating that the main areas studied are: multiple objective optimizations, execution of the design, general DFAM and DFAM for functional performance. Among the main conclusions: there is a lack of innovation in the products developed with the methodologies, there is a lack of exhaustivity in the methodologies, there are few efforts to include environmental aspects in the methodologies, many of the methods include economic and cost evaluation, but are not very explicit and broad (sustainability evaluation), it is necessary to consider a greater variety of functions, among other conclusions

The novelty in this study is the methodology. It is very objective, comprehensive and quantitative. The starting point is not the case studies nor the qualitative criteria, but the figures and quantities of methodologies. The main contribution of this review article is to guide future work on the subject from a methodological and convergent perspective and this article provides a broad database with articles containing information on many issues to make decisions: design methodology; optimization; processes, selection of parts and materials; cost and product management; mechanical, electrical and thermal properties; health and environmental impact, etc.

Mechanical reliability (variations in mechanical properties) of fused deposition modeled (FDMed) short-fiber-reinforced composites are unknown, which limits wider and safer use of these composites. Accordingly, this paper aims to investigate the mechanical reliability of FDMed model material short-carbon-fiber-reinforced acrylonitrile butadiene styrene (SCFR-ABS). A new vibration-assisted FDM (VA-FDM) process was used to reduce porosity.

Tensile tests were performed on FDMed SCFR-ABS produced with and without vibrations. Weibull analysis was performed to quantify the variation in fracture strength, tensile strength, strain at break and strain at tensile strength.

Introduction of vibrations to the extrusion head during FDM decreased the inter-bead porosity in SCFR-ABS and thus improved elastic modulus, toughness, fracture strength, tensile strength and strain at break. Weibull modulus of fracture strength increased from 25 to 57 with vibrations.

The reported Weibull analysis offers a practical design guideline to predict failure rates at specific service stresses.

A detailed Weibull analysis of the variations in the mechanical properties of FDMed SCFR-ABS was performed for the first time. A new vibration-assisted FDM process was reported to reduce inter-bead porosity in FDMed composites.

This study aims to examine whether social capital contributes to service firms' resilience during crisis.

This study measures social capital via environmental and social (ES) ratings and firm performance via buy-and-hold-abnormal returns derived from Refinitiv ESG and CRSP databases. Using a sample of 404 US service firms, this study runs cross-sectional regressions to estimate the effect of social capital on service firms' crisis returns.

This study finds that high-social capital service firms outperformed in the first quarter of 2020. The crisis response is heterogeneous among service sub-sectors and diverges (i.e. calming or deepening) over time depending on social capital. Service sub-sector analysis notably posits that social capital impact is positively related to returns of Health- and Business Services and firms with utilitarian nature. The study also indicates that ES commitments targeting internal stakeholders contribute more to resilience. Overall, social capital might be a relevant value driver, generate real impact and provide insurance-like protection for service firms during turmoil.

The service industry is one of the most severely hit industries during COVID-19. However, there is limited knowledge about whether and when social capital creates value in the service industry during crises. This study makes two main contributions: first, it extends to the continuous efforts toward the role of social capital in firm performance, and second, it provides important insights related to the resilience search for service firms.

This study aims to examine the information acquired and shared by floods victims in Sarawak, Malaysia, and the individuals’ perception of social media information quality and awareness of social media emergency services.

The research data were gathered from 118 victims in two flood-ravaged villages with a researcher-administered questionnaire survey. Meanwhile, the research instrument was adopted from Reuter and Spielhofer (2017).

Resultantly, 93% of the respondents employed social media for information-seeking and sharing during floods. For example, Facebook was the most extensively employed digital platform. The most highly sought and exchanged information involved eyewitness pictures or videos, road or traffic conditions and weather conditions or warnings. Although social media information quality reflected faster obtainability, higher accessibility and enriched content, respondents’ viewpoints of social media information quality regarding accuracy and reliability proved negative. Notably, over half of the respondents were unaware of the two social media emergency services: Twitter Alerts and Facebook Safety Check.

This study denoted one of the rare empirical works that explored social media usage for information-seeking and sharing by the flood victims in Sarawak based on the boundary object perspective.

Fused filament fabrication of continuous-fiber-reinforced polymers is a promising technique to achieve customized high-performance composites. However, the off-axis tensile strength (TS) and Mode I fracture toughness of fused filament fabricated (FFFed) continuous-glass-fiber-reinforced (CGFR) nylon are unknown. The purpose of this paper is to investigate the mechanical and fracture behavior of FFFed CGFR nylon with various fiber content and off-axis fiber alignment.

Tensile tests were performed on FFFed CGFR-nylon with 9.5, 18.9 and 28.4 fiber vol. %. TS was tested with fiber orientations between 0^∘ and 90^∘ at 15^∘ intervals. Double cantilever beam tests were performed to reveal the Mode I fracture toughness of FFFed composites.

TS increased with increasing fiber vol. % from 122 MPa at 9.5 vol. % to 291 MPa at 28 vol. %. FFFed nylon with a triangular infill resulted in 37 vol. % porosity and a TS of 12 MPa. Composite samples had 11–12 vol. % porosity. TS decreased by 78% from 291 MPa to 64 MPa for a change in fiber angle θ from 0^∘ (parallel to the tensile stress) to 15^∘. TS was between 27 and 17 MPa for 300 < θ < 900. Mode I fracture toughness of all the composites were lower than ∼332 J/m2.

Practical applications of FFFed continuous-fiber-reinforced (CFR) nylon should be limited to designs where tensile stresses align within 15^∘ of the fiber orientation. Interlayer fracture toughness of FFFed CFR composites should be confirmed for product designs that operate under Mode I loading.

To the best of the authors’ knowledge, this is the first study showing the effects of fiber orientation on the mechanical behavior and effects of the fiber content on the Mode I fracture toughness of FFFed CGFR nylon.