Display omitted
•This paper summarizes diverse perspectives from researchers on binder aging.•This paper explores binder aging’s chemical, morphological, and rheological aspects.•This paper urges ...better methods for understanding binder aging phenomenon.
Asphalt binders, an indispensable component in road infrastructure construction and maintenance, have been utilized for centuries in the roads. While binders have demonstrated durability and resilience to growing climatic and traffic stressors, concerns persist regarding their susceptibility to aging, a factor that can significantly affect the performance and longevity of asphalt pavements. To address these concerns, extensive research is ongoing to continuously improve our understanding of aging on asphalt binders, employing a multi-aspect characterization approach. In this review paper, we aim to offer a comprehensive and insightful summary of the diverse perspectives provided by researchers on the intricate effects of aging on asphalt binders. We study the chemical, morphological, and rheological aspects of asphalt binder aging, shedding light on the multifaceted changes that occur as these materials mature over time. This cutting-edge approach provides a deeper understanding of the complex processes that underlie asphalt binder aging, keeping the industry up-to-date with the latest findings and breakthroughs. The overarching goal of this review paper is to inspire and motivate asphalt binder researchers to adopt a more holistic approach to characterization, one that considers multiple aspects of the aging phenomenon. By doing so, we can better understand how asphalt binders evolve and degrade over time, ultimately leading to more effective and long-lasting pavements. Furthermore, this review paper highlights the limitations of current methods and technologies, emphasizing the necessity for advancements in the field of asphalt binder aging characterization.
The predominant focus of academic research on the sharing economy has been on Airbnb and Uber; to this extent, the diversity of business models ascribed to the sharing economy has not yet been ...sufficiently explored. Greater conceptual and empirical research is needed to increase understanding of business models in the sharing economy, particularly attributes that deliver on its purported sustainability potential.
We aimed to elaborate an improved sharing economy business modelling tool intended to support the design and implementation of sharing economy business models (SEBMs) with improved sustainability performance.
We used a structured approach to business modelling, morphological analysis, to articulate relevant business model attributes. Our analysis was informed by a narrative literature review of business and platform models in the sharing economy. We also iteratively tested, refined, and evaluated our analysis through three structured opportunities for feedback.
The output of the morphological analysis was a sharing economy business modelling tool for sustainability, with stipulated preconditions and descriptions of all business model attributes.
The sharing economy is not sustainable by default, so we must be strategic and deliberate in how we design and implement SEBMs. The sharing economy business modelling tool should be of interest not only to researchers and practitioners, but also to advocacy organisations and policymakers who are concerned about the sustainability performance of sharing platforms.
•The sharing economy is not sustainable by default.•Reviews existing sharing economy business model conceptualisations.•Proposes preconditions to scope business and consumption practices for improved sustainability performance by sharing platforms.•Conducts morphological analysis depicting and describing all relevant business model attributes.•Presents a sharing economy business modelling tool to overcome the design-implementation gap of sustainable business models.
This paper presents a novel signal processing scheme, bandwidth empirical mode decomposition, and adaptive multiscale morphological analysis (BEMD-AMMA) for early fault diagnosis of rolling bearings. ...In this scheme, we propose a bandwidth based method to select the best envelope interpolation method. First, multiple envelope algorithms are defined and separately subtracted from the original data to obtain the preintrinsic mode functions (PIMFs). Second, an IMF with the smallest frequency bandwidth is selected to be the optimal IMF (OIMF). Third, this OIMF is subtracted from the original signal, and then repeat the sifting process until the residual is a constant or monotonic. Since the OIMF has the smallest frequency bandwidth, the mode mixing phenomenon can be significantly weakened. After that the OIMFs with clear fault information are used to construct the main component of the original signal. Then, the AMMA is introduced to demodulate the constructed main component. Simulation and experimental vibration signals are employed to evaluate the effectiveness of the proposed method. Results show that the proposed method outperforms EMD-AMMA, ensemble empirical mode decomposition-AMMA, and generalized empirical mode decomposition-empirical envelope demodulation in detecting early inner race fault.
Display omitted
•A rapid in-situ pre-coated dynamic membrane formation method was developed.•PC-AnDMBR showed a slightly better pollutants removal compared to SF-AnDMBR.•Stable performance with low ...TMP increasing rate (0.07 kPa/d) was obtained in PC-AnDMBR.•Gel layer rather than cake layer contributed more to the total filtration resistance.•Gel layer showed the properties of more organics accumulation and lower porosity.
Precoated dynamic membranes (PCDM), commonly formed by retaining external particles on coarse supporting meshes, can accelerate dynamic membrane (DM) formation, change the DM structure, and enhance its filtration performance. An in-situ rapid PCDM formation method via short-time and high-flux initial filtration (at 380 L/m2·h flux for 0.25 min) is proposed using anaerobic sludge as a precoating material. A precoated anaerobic dynamic membrane bioreactor (PC-AnDMBR) was operated in parallel with a self-forming AnDMBR (SF-AnDMBR) to treat domestic wastewater. Extremely low rates of transmembrane pressure (TMP) increase of 0.05 and 0.07 kPa/d were obtained during the long-term operation of the SF-AnDMBR and PC-AnDMBR, respectively. Furthermore, the PC-AnDMBR and SF-AnDMBR showed stable effluent turbidity (27.1 ± 9.44 NTU and 31.35 ± 15.96 NTU, respectively) and satisfactory COD removal (83% and 78%, respectively), which were attributed to the small pore size (<2 μm) of the DM layers. The PCDM and self-forming dynamic membrane (SFDM) with a thickness of 0.7 mm were further characterized as cake and gel layers, whereas the gel layer thickness within the PCDM was higher than that of the SFDM (0.6 mm vs. 0.2 mm). In addition, the porosities of the gel layers (2.87% and 2.95%) were lower than those of the cake layers (3.58% and 3.48%) for the PCDM and SFDM, respectively. Therefore, the compact gel layer, with more accumulated organics, contributed to over 78% of the total filtration resistance. These findings provide new insights into the mechanisms of PCDM formation and the application of AnDMBRs in wastewater treatment.
This study aims to investigate the use of morphological analysis strategy in enhancing the student’s vocabulary acquisition and reading comprehension. The research was experimented in the English ...Department at Universitas Muhammadiyah Parepare, with a total sample of 28 students. This study was pre-experiment research with a pretest-posttest design. The result of this study indicated that: (1) in teaching vocabulary through vocabulary analysis strategy, there are significant differences between the mean score of the pre-test (58.57) and the mean score of the post-test (84.28). Besides that, the result of the t-test calculation shows that the t-test value (7.75) is higher than the t-table value (2.052) at a significance level 0.05 from df = 27. (2) In teaching reading comprehension through vocabulary analysis strategy, there are also significant differences between the mean score of the pre-test (54.64) and the mean score of the post-test (80.51). In addition, the result of the t-test calculation shows that the t-test value (9.75) is higher than the t-table value (2.052) at the significance level 0.05 from df = 27. Thus, the student’s vocabulary acquisition and reading comprehension significantly improve after they are taught using the morphological analysis strategy.
Purpose
The purpose of this paper is to review the existing literature on Lean Six Sigma (LSS) for services, construct a morphological analysis (MA) framework and identify research gaps to point to ...future research possibilities and priorities.
Design/methodology/approach
The MA framework is based on literature review of 175 papers published from 2003 to 2015, across 67 journals recognised by Scopus or ABS Academic Journal Quality Guide 2015. A three-phased methodology is used by the authors, with Phase1 featuring a five-stage systematic review protocol to identify relevant journal papers for review; Phase2 presenting a framework for classifying the reviewed papers in terms of their fundamental, methodological, chronological and sector-wise orientations; and Phase3 constructing an MA framework on the classified papers and identifying the research gaps.
Findings
The MA framework constructed based on six dimensions, namely, organizational context of applications, desired outcomes, implementation systems, LSS tools and techniques, integration with other management philosophies and evaluation methods, involving 40 focused themes, has revealed 355 distinct research gaps as opportunities for future research.
Practical implications
This paper confirms the existence of substantial scope and points to specific topics for further research in the area of LSS for services. The findings demonstrate the gaps in academic research on the subject. In addition, the study also helps organisational leaders and practitioners to look at LSS from a holistic perspective in the services context.
Originality/value
The MA framework of the existing literature on LSS for services presents a unique, systematic effort to identify research opportunities. In addition, a five-stage systematic review protocol is proposed in this paper. This could be valuable to researchers and practitioners in enabling them to systematically review the literature on research subjects of interest to them.
In the present article, the pure PbS and different concentrations of Gd doped PbS (Gd:PbS) films were developed using the spray pyrolysis route by growing thin films on the glass substrate. The ...estimated crystallite sizes were found from 15.5 to 20.8 nm for as-deposited films. The spherical shape morphology of grains was observed by FESEM. The obtained average grain sizes varied from 52.8 to 108.2 nm were obtained from the grain size distributions for 0.0, 0.5, 1.5, and 2.5 wt % Gd: PbS films, respectively. Extinction coefficients of as-deposited films were measured from 0.04 to 0.12 in the range of wavelength 200–2500 nm. Refractive indices of films were obtained from 5.4 to 1.22 in range of 200–2500 nm wavelength. The band gaps of 2.75, 2.64, 2.45, and 3.10 eV for 0.0, 0.5, 1.0 and 2.5 wt % Gd thin films were estimated using Tauc's relation respectively. The values of the dielectric constant, dielectric loss, and optical conductivity were recorded in the range of 1.32–29.6, 0.30–0.61, and 2.34 × 1014–3.08 × 1013 between 200 and 2500 nm wavelengths for as-deposited thin films respectively. The optimum values of linear susceptibility, non-linear susceptibility and refractive index were recorded in the range of 1.23–2.93, 5.21 × 10−10 - 120 × 10−10, 3.54 × 10−9 – 74.2 × 10−9 (esu) between 1.46 and 0.52 eV respectively for as-deposited thin films. The Gd: PbS thin films improve the physical properties and therefore, it becomes suitable candidature for the applications in optoelectronic devices.
•Fabrication of PbS and Gd:PbS films on glass by nebulizer spray pyrolysis is reported.•Spherical grains with highly packed structure of PbS and Gd:PbS thin films.•Homogeneous doping of Gd in ZnO was detected by EDX/SEM mapping.•The band gaps is noticed in range of 2.45–3.10 eV for PbS and Gd:PbS thin films.•Values of linear/non-linear susceptibilities, and non-linear refractive index of Gd: PbS decreases as compared to pure.
A fungal strain designated KNUF-22-014, belonging to the family Ophiocordycipitaceae, was isolated from a soil sample collected in Sobaeksan National Park, South Korea. Phylogenetic trees based on ...the combined sequences of internal transcribed spacer (ITS) regions and the large subunit of 28S rRNA (LSU) gene, as well as on five concatenated loci (LSU, ITS, translation elongation factor 1α, β-tubulin, and subunit 1 of RNA polymerase II), revealed that the isolate falls within the clade containing the genus Tolypocladium but occupies a distinct phylogenetic position. Its closest relative is T. tropicale. Morphologically, strain KNUF-22-014 can be distinguished from T. tropicale by the shape of its phialides (subcylindrical vs. lageniform), its conidiophore type (arborescent or unbranched vs. trichodermatoid), and its larger conidia size (2.1 ± 0.1 µm vs. 1.5 ± 0.1 µm). Phylogenetic analysis and morphological observations indicate that KNUF-22-014 represents a novel species in the genus Tolypocladium, for which the name Tolypocladium sobaeksanense sp. nov. is proposed.
A microwave combustion method was used to synthesize Cu1-xZnxFe2O4 (x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5) nanoparticles. The synthesized Zn-doped CuFe2O4 nanoparticles were characterized by techniques ...such as X-ray diffraction, high-resolution scanning electron microscopy, UV–visible diffuse reflectance spectroscopy, photoluminescence spectroscopy, Fourier transform IR spectroscopy, and vibrating sample magnetometry. X-ray diffraction and Fourier transform IR spectroscopy results confirmed the formation of Cu1-xZnxFe2O4(x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) nanoparticles. The crystallite size and lattice parameter were determined as 15–19 nm and 8.319–8.400 Å, respectively. High-resolution scanning electron microscopy revealed the presence of agglomerated spherical particles of Cu1-xZnxFe2O4. Elemental mapping of pure and Zn-doped CuFe2O4 was done by energy-dispersive X-ray analysis. The band gap was calculated with the Kubelka-Munk function and was found to lie in the range from 2.30 to 2.51 eV. Finally, M-H curves were plotted and the magnetic properties, such as coercivity, remanent magnetization, and saturation magnetization, were determined.
Display omitted
•Zinc-doped copper ferrite was synthesized by a microwave combustion method.•Structural, morphological, optical, vibrational, and magnetic properties are studied.•Zinc-doped copper ferrite nanoparticles exhibit ferromagnetic behavior.
PDF
