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1.
Although several studies have used sentiment analysis to examine social media content, relatively few have complemented this work with sociological theories. This study employed the diffusion of innovation (DOI) framework to provide a deeper understanding of the recent debate on whether women in Saudi Arabia should be granted the right to drive. The outlook of proponents and opponents was considered by using detailed Arabic Twitter data. The sentiment analysis approach was used. The findings were analyzed on the basis of DOI stages, and the innovation–decision process demonstrated that 60% of Twitter users supported the governments' approval of women's right to drive and 40% either opposed the order or had a neutral opinion. The finding of our analysis suggests that Saudi society corresponds the DOI stages and exhibits the tendency to support the right of women to drive. This study contributes to DOI research, particularly concerning the use of social media for studying opinions on important unsettled social matters. 相似文献
2.
This study proposed a methodology that integrate sociotechnical systems (STS) and media big data analysis using text mining for the new, real-time technology assessment (TA). The essential steps of this method are composed of data collection using a cultural map, analysis with trends and patents, and synthesis using media big data. By applying this methodology to artificial organs, first, we have shown that STS can be apply to biosocial technical systems beyond the sustainability transition. The result reveals that a media discourse structures, in which eight countries began to form socio-technical regimes around technologies with their respective strengths, in an objective way. Each technology corresponded to the vested interests in each country's socio-technical regimes. These discourse structures helped us to identify substitution, two types of transformation, and reconfiguration as transition pathways. More importantly, our analysis results have also shown that the methodology helps to overcome the anticipation dilemma, saving the time and resources required for TA. Our integrated methodology has achieved similar results by using 23% of the budget, 25% of the time, and 14% of the work hours used for official TA. Lastly, the “objectivity” and “agenda setting” of this methodology can provide a breakthrough in overcoming the control dilemma. 相似文献
3.
Many older adults find it difficult to accept new forms of information and communication technology (ICT), despite its advantages such as convenience and efficiency. It is necessary to identify the reasons for low ICT use among older people—even among those with positive attitudes toward ICT—to help older adults cope with social changes and bridge the digital divide. This study explored technology acceptance and related factors among older Korean adults living in rural areas. Based on an existing model (the senior technology acceptance model), a new conceptual framework for technology acceptance was proposed, and the framework was tested using pathway analysis. Semi-structured interviews were conducted in three focus groups (n = 15), and a survey questionnaire was administered to older Korean adults living in a rural area (n = 233) from 17 January 2021 to 18 February 2021. Qualitative data were analyzed using directed content analysis, and quantitative data were analyzed using pathway analysis. Four categories, 11 subcategories, and 18 codes were identified, and a new conceptual framework was proposed based on the qualitative findings. The results of the model revealed significant positive direct paths from external controls (β = 0.45, p < .001), attitudinal beliefs (β = 0.33, p < .001), and cognitive health (β = 0.10, p = .040) to internal abilities. It is necessary to develop and apply a targeted and tailored ICT education program to improve self-efficacy and reduce anxiety regarding technology use among older Korean adults living in rural areas. 相似文献
4.
《Advanced Powder Technology》2020,31(10):4365-4375
To address the mixing uniformity of multiple organic hydraulic (MOH) mixtures in a continuous mixer, three types of mixing parameters and their coupling effects were studied by the discrete element method (DEM) and response surface methodology. To achieve the research goal, only one parameter was selected for each type of parameter, and the corresponding model was established. Numerical simulations and optimization were implemented. A three-level, three-factor Box-Behnken Design method combined with response surface methodology was applied for the numerical design. The influence of the parameters on the mixing uniformity of the mixture was analyzed by analysis of variance (ANOVA). The ANOVA results show that the rotation speed, the installation angle, the filling ratio and the coupling between the rotation speed and the filling ratio have a significant effect on the mixing uniformity of the mixture, that the rotation speed and the filling ratio have the strongest effect on the response, and that of the fitting model of the mixing uniformity can fit the simulation data well. The coupling effect results show that the influence of coupling between the revolution and installation angle on the mixing uniformity is consistent with that between the filling ratio and installation angle and that the coupling effect between the rotation speed and the filling ratio is different. It is also found that the optimal parameter range under one factor is different from that under multivariable coupling. The optimization results show that when the discrete coefficient is the smallest, the optimal combination of the parameters is a revolution of 350 r/min, an installation angle of 25°, and a filling ratio of 70%. The experimental results are consistent with the optimization results, which indicate the correctness of the parameter optimization results. 相似文献
5.
Unless just and inclusive, transitions to low carbon-energy systems are unlikely to receive sufficient legitimacy and broad public support. While research on inequalities and injustices in energy transitions is growing, these issues remain less explored in the case of the digitalisation of the energy systems through smart grids and smart homes. This paper aims to synthetise our understandings of inequality, exclusion and vulnerability in energy transitions by systemically analysing different dimensions of marginalisation in the transition to a digitalised electricity infrastructure in Sweden. To synthetise understandings of marginalisation and exclusion, conceptualisations of these processes in different social science approaches to energy studies are reviewed. Moreover, an empirical analysis of interviews with a range of Swedish actors such as energy utilities, social housing developers or pensioner organisations is carried out and enriched by previous research on smart grid users. The empirical analysis demonstrates what specific forms that diverse categories of marginalisation, as already identified generally in different social science approaches to energy studies, may take in smart grids. We argue that marginalisation of household users in smart grids may take place along multiple dimensions, relating to matters of literacy, participation, infrastructure, and the economy. The analysis suggests that bundles of marginalisation aspects concerning household users in sustainable energy transitions should be recognised and addressed simultaneously. 相似文献
6.
《Current Opinion in Solid State & Materials Science》2023,27(4):101091
The solution of instrumented indentation inverse problems by physically-based models still represents a complex challenge yet to be solved in metallurgy and materials science. In recent years, Machine Learning (ML) tools have emerged as a feasible and more efficient alternative to extract complex microstructure-property correlations from instrumented indentation data in advanced materials. On this basis, the main objective of this review article is to summarize the extent to which different ML tools have been recently employed in the analysis of both numerical and experimental data obtained by instrumented indentation testing, either using spherical or sharp indenters, particularly by nanoindentation. Also, the impact of using ML could have in better understanding the microstructure-mechanical properties-performance relationships of a wide range of materials tested at this length scale has been addressed.The analysis of the recent literature indicates that a combination of advanced nanomechanical/microstructural characterization with finite element simulation and different ML algorithms constitutes a powerful tool to bring ground-breaking innovation in materials science. These research means can be employed not only for extracting mechanical properties of both homogeneous and heterogeneous materials at multiple length scales, but also could assist in understanding how these properties change with the compositional and microstructural in-service modifications. Furthermore, they can be used for design and synthesis of novel multi-phase materials. 相似文献
7.
《Advanced Powder Technology》2023,34(11):104204
We developed a stable OpenFOAM solver for Immersed Boundary Method based on direct forcing and regularized delta function. The soft-sphere model and a lubrication model were implemented to consider particle–particle collision in a viscous flow. We proposed a fluid–structure interaction (FSI) coupling method to accurately calculate the fluid forcing term and particle velocity. Our solver was validated for fixed and moving bodies, including rotation. The accuracy of various FSI schemes was evaluated in predicting the solid and fluid flow behavior in a viscous flow. It was demonstrated that neglecting or simplifying the fluid momentum change affects the accuracy of the solid velocity and fluid flow dynamic; for higher solid-to-fluid density ratios, a larger deviation was predicted. Furthermore, the FSI schemes highly influenced the behavior of the formed vortices.The solver was validated to predict the effective restitution coefficient of particles in a viscous flow as a function of the Stokes number. We also thoroughly analyzed the dynamic flow behavior of colliding particles through the pressure and velocity field and fluid force. This analysis helped us accurately determine the rebound velocity of particles in case of high Stokes numbers when the effect of viscous force is significant. 相似文献
8.
The study analyzes the dynamics of the protection of biotechnology in Brazil through the patent documents. Data analysis was carried out through the use of protective measures aiming to understand the dynamics of development and protection involving biotechnological knowledge in the health, industrial, agricultural and environmental sectors outlined in the Biotechnology Development Policy. In the protection measures, a new method was based on claims data and their relationships. Different trajectories and associations for the protection of biotechnology were shown producing information can be used as a source of support for the patenting and management of intellectual property in the area. 相似文献
9.
《Advanced Powder Technology》2020,31(2):658-669
In the present work, computational fluid dynamics (CFD) based modelling of an industrial scale continuous fluidised bed roaster (FBR) has been carried out to study its performance at different operating conditions, so that the sulphide-sulphur content in the product is within 0.4% at the designed feed rate of 39.75 DMT/h. Eulerian-Eulerian multiphase model, considering four granular phases and one gas phase has been implemented to investigate the velocity and mass fraction profile of the particles in the FBR. The heat and species mass balance calculations have been performed external to CFD, by dividing the roaster into several sections. The conversion of ZnS to ZnO at various sections of the roaster has been estimated using reaction kinetics under isothermal condition (1203 K). The heat liberated and possible temperature rise at each section was predicted based on the heat of reaction and sensible heat of the solid and gaseous products. The CFD model was validated with the plant data for a feed rate of 36.5 DMT/h, air flow rate of 65,000 Nm3/h and O2 content of 21%. The proposed model predicted the sulphide-sulphur content in the product to be 0.4% for the designed feed rate of 39.75 DMT/h, when the O2 content in the inlet air was increased to 25%. 相似文献
10.
Implementing an industrial collaborative robot for Human-Robot Collaboration (HRC) in the automotive manufacturing industry is an emerging technology-driven solution aiming to increase production efficiency and reduce the human operator's ergonomic load. Successful implementation of innovative technology depends on technical feasibility and on the acceptance by the affected actors. Many studies exist that focus on the technical aspects of HRC, however, research that focuses on understanding the multi-actor concerns of HRC adoption is rare. In an effort to support the successful adoption of industrial collaborative robots, this study aims to understand the concerns of the various actors who work at the operational and management levels influencing future HRC adoption in the heavy automotive manufacturing industry.A literature review was conducted to understand the HRC implementation challenges and the methods used to investigate multi-actor involvement in advance of, and during, the implementation stage. After reviewing existing studies, the actor analysis method was selected to present the actors' perceptions using the action, factor, and goal (AFG) list to understand different actors’ opinions of HRC adoption, using a Swedish heavy vehicle manufacturing company case study.The case study results showed that the actors from the same organization had different concerns but mostly positive expectations for future HRC adoption. The actors’ perception map shows the details pertaining to Actions, Concerns, and Goals as well as the logical flow between these elements in regards to HRC future adoption. The involvement of different actor groups prior to new solution implementation contributes to a holistic view of potential implementation influences and challenges in the organization. Actor analysis can provide a set of analysis processes that comply with multi-actor perceptions to understand future adoption challenges from different perspectives. In the next step, safety-related issues and under-development standardization are the key challenges of HRC implementation. 相似文献
11.
Laboratory diagnosis of pathologies caused by virus plays a critical role in outbreak response efforts and establishing safe and expeditious testing strategies. Detection of pathogenic virus using commercial solutions require specific tools and laborious laboratory procedures. This makes the day-to-day on time detection of virus infections the limiting step in any outbreak. The need for new diagnostic tools easily available to poor and rural underdeveloped areas where health infrastructure and trained personnel are scarce is highly desirable. The widely known intrinsic properties of Metal-Organic Frameworks (MOFs) embody them with the potential to overcome some of the challenges inherent to virus detection. MOFs are already components of functional devices capable of perform an uninterrupted detection of molecular targets in real time. In this review, we summarise the few studies concerning the reported MOFs used as sensors for pathogenic virus. We emphasise the structural and physical properties of these materials which can open the possibility for their use in this type of sensors and conclude on how the field can progress to envisage the usage of MOFs by the pharmaceutical industry to develop new sensors for these sub-microscopic infectious agents. 相似文献
12.
《Current Opinion in Solid State & Materials Science》2022,26(5):101016
Piezo-/ferroelectric materials with high Curie temperature (TC) are widely needed in sensors, actuators and transducers which can be used for high-temperature (HT) electromechanical transduction applications. In recent years, remarkable progress has been made in bismuth-based piezo-/ferroelectric perovskite materials (BPPs). In this article, recent progress in high TC BPPs is reviewed. This review starts with an introduction to HT piezoelectrics and their applications. A detailed survey is then carried out on bismuth-based perovskites (BPs) with high TC. Material synthesis, doping effects and chemical modifications of the related solid solutions are examined. Based on this analysis, the structure–property relationship of these materials is established. In addition, recent developments of BPPs for HT electromechanical transduction applications are presented and evaluated. Lastly, some main existing issues are analyzed and their possible solutions are proposed. This article provides a comprehensive overview of the research and development of BPPs and offers some prospects towards making these materials a viable resource for the design and fabrication of electromechanical transducers with unique specifications, especially, high temperature, high frequency and high power, for a wide range of technological applications. 相似文献
13.
Satoshi Nogami Katsuhiko Minoura Nao Kiminami Yui Kitaura Hiromasa Uchiyama Kazunori Kadota Yuichi Tozuka 《Advanced Powder Technology》2021,32(5):1750-1756
Although curcumin is considered to have various therapeutic effects, its use as a functional food or supplement is restricted owing to its low water solubility and bioavailability. To increase the solubility of curcumin in water, the use of polyvinylpyrrolidone (PVP) and vinylpyrrolidone-vinyl acetate copolymers with a pyrrolidone skeleton was noted to be promising. In particular, the bi-component formulations of curcumin/PVP prepared through spray drying exhibited an amorphous state in powder X-ray diffraction observations and temporally increased the apparent solubility of curcumin to over 5000 times that of untreated curcumin; nevertheless, after 24 h, the solubility decreased owing to the unstable supersaturated state of curcumin. The addition of α-cyclodextrin (α-CyD) in the bi-component curcumin/PVP formulation helped maintain the supersaturated state of curcumin, whereas the addition of β- and γ-CyD led to the collapse of the supersaturated state. The addition of α-CyD can likely help inhibit the nucleation and crystal growth of curcumin, through the interaction among the solubilized units of curcumin/PVP and α-CyD. 相似文献
14.
Cong-Binh Dinh Shu-San Hsiau Chien-Yuan Su Meng-Yuan Tsai Yi-Shun Chen Huy-Bich Nguyen Hou-Peng Wan 《Advanced Powder Technology》2021,32(3):670-682
The unsteady behaviors of the air-silica sand flow in a lab-scale dual fluidized bed gasification cold flow system have been studied. A two-dimensional computational fluid dynamics full-loop model with poly-size distribution in solid phases was developed as an innovation of this study to investigate the effects of crucial parameters on system hydrodynamics. The results showed a decrease in the mixture static pressure from the bottom to the upper regions of the system, which maintained the system operations stable. The riser air inlet velocity and the gasifier static bed height were found to play considerable roles in enhancing the total sand flow rates. The same tendencies in the prediction and experiment of both the mixture pressure and the sand flow rate showed the feasibility of the proposed model. Besides, the residual evaluation enhanced data reliability and supported model validation. Especially, undesirable phenomena possibly occurring in the system operation under improper conditions could also be predicted. Accordingly, the inventory of bed material and the fluidizing gas flow rates should be suitably regulated to maintain pressure balances, trouble-free continuous flow, optimal sand circulation rate, and low solids loss. Furthermore, the obtained results in this study can be used as a reference for optimizing the designs and operational conditions of large-scale plants. 相似文献
15.
This paper presents a narrative literature review that addresses the issue of how disabled and aging people access the arts through technology. Our review synthesized 56 studies about disabled and aging people's experiences of access through technology, with a focus on methods used and accounts of user experiences/stories to inform a Canadian research and development initiative called Accessing the Arts. We urge designers and developers to consider the complex, multimodal sociotechnical relationships surrounding technology and access—or TechnoAccess—as they develop technology with disability, aging and access in mind. Although existing evidence offers ways to improve everyone's access to the arts, recommendations are provided for research around access and technology as an inherently politicized topic that must be informed by disabled and aging people's intersectional cultural experiences, including how they wish to use technology to access the arts. 相似文献
16.
《Advanced Powder Technology》2023,34(7):104047
This study mainly investigated the physicochemical characteristics of ethylene glycol/ water (EG/W) based hydroxyl-functionalized boron nitride (BN-OH) and graphite (G) hybrid nanofluids. A novel simple and efficient annealing method was proposed to have hexagonal boron nitride (h-BN) nanoparticles functionalized to improve the synergistic role between hybrid G/BN-OH nanoparticles. Meanwhile, the dispersion stability, thermal stability, and rheological behavior of diverse nanofluids (h-BN, BN-OH, G, G/BN and G/BH-OH) were comprehensively evaluated. The results showed that the G/BN-OH hybrid nanofluids demonstrate both better dispersion stability and thermal stability, as well as a lower increase in viscosity. In addition, the thermal conductivity of G/BN-OH hybrid nanofluids was increased by up to 18.05% with a concentration of 0.2 wt% when compared to the base fluid. Ultimately, the complicated theoretical mechanism of thermophysical performance augment for G/BH-OH hybrid nanofluids was reliably presented. The enhanced thermal conductivity of nanofluids may be attributed to the formation of adsorption layers and the synergistic effect of the thermal conductivity network. 相似文献
17.
Ni-rich layered oxides (NRLOs) and Li-rich layered oxides (LRLOs) have been considered as promising next-generation cathode materials for lithium ion batteries (LIBs) due to their high energy density, low cost, and environmental friendliness. However, these two layered oxides suffer from similar problems like capacity fading and different obstacles such as thermal runaway for NRLOs and voltage decay for LRLOs. Understanding the similarities and differences of their challenges and strategies at multiple scales plays a paramount role in the cathode development of advanced LIBs. Herein, we provide a comprehensive review of state-of-the-art progress made in NRLOs and LRLOs based on multi-scale insights into electrons/ions, crystals, particles, electrodes and cells. For NRLOs, issues like structure disorder, cracks, interfacial degradation and thermal runaway are elaborately discussed. Superexchange interaction and magnetic frustration are blamed for structure disorder while strains induced by universal structural collapse result in issues like cracks. For LRLOs, we present an overview of the origin of high capacity followed by local crystal structure, and the root of voltage hysteresis/decay, which are ascribed to reduced valence of transition metal ions, phase transformation, strains, and microstructure degradation. We then discuss failure mechanism in full cells with NRLO cathode and commercial challenges of LRLOs. Moreover, strategies to improve the performance of NRLOs and LRLOs from different scales such as ion-doping, microstructure designs, particle modifications, and electrode/electrolyte interface engineering are summarized. Dopants like Na, Mg and Zr, delicate gradient concentration design, coatings like spinel LiNi0.5Mn1.5O4 or Li3PO4 and novel electrolyte formulas are highly desired. Developing single crystals for NRLOs and new crystallographic structure or heterostructure for LRLOs are also emphasized. Finally, remaining challenges and perspectives are outlined for the development of NRLOs and LRLOs. This review offers fundamental understanding and future perspectives towards high-performance cathodes for next-generation LIBs. 相似文献
18.
《Advanced Powder Technology》2020,31(5):2092-2100
Tapered wire coil insert is proposed as a novel enhancer in the double tube heat exchanger and experimental studies on Al2O3 + MgO hybrid nanofluid flowing under the turbulent condition are performed to investigate the hydrothermal characteristics. Effects of using tapered wire coil turbulator and hybrid nanofluid on the hydrothermal behaviors are examined for different coil configurations (Converging (C) type, Diverging (D) type and Conversing-Diverging (C-D) type) and hybrid nanofluid inlet temperatures and volume flow rates. Results show that D-type wire coil insert promotes better hydrothermal performance as compared to C-type and C-D type. Nusselt number and friction factor of hybrid nanofluid using D-type, C-D type and C-type wire coil inserts enhance up to 84%, 71% and 47%, and 68%, 57% and 46%, respectively than that of water in tube without insert. The entropy generation of hybrid nanofluid is lower than that of base fluid in all cases. The thermal performance factor for hybrid nanofluid is found more than one with all inserts. The thermal performance factor is observed a maximum of 1.69 for D-type coil. The study reveals that the hybrid nanofluid and tapered wire coil combination is promising option for improving the hydrothermal characteristics of double pipe heat exchanger. 相似文献
19.
《Advanced Powder Technology》2022,33(12):103879
Heat transfer within ceramic feedstock powders is still unclear, which impedes optimization of the thermal and mechanical properties of the thermal sprayed coatings. The microspheres (yttria-stabilized zirconia YSZ and lanthanum zirconate LZO) were prepared via the electro-spraying assisted phase inversion method (ESP). The thermal properties of the two ESP microspheres and a commercial hollow spherical powder (HOSP) were investigated by using theoretical, experimental, and simulation methods. Thermal conductivity of the single microsphere was estimated via a novel nest model that was derived from the Maxwell-Eucken 1 and the EMT model. Thermal conductivity of a single YSZ/LZO-ESP microsphere prepared at 1100–1200 °C was within 0.36–0.75 W/m K, which was ~ 20 % lower than that of a single YSZ-HOSP microsphere with a similar porosity. Heat flux simulation showed that high tortuosity around the multi-scaled voids of the ESP microsphere led to a more efficient decrease in thermal conductivity compared with total porosity. 相似文献
20.
《Advanced Powder Technology》2020,31(3):1114-1124
The prefabrication of Mo-Nb composite powders is an effective way of improving the homogeneity of Mo-10Nb targets, which have broad application prospects in the photoelectric sensor industry. However, this aspect has been rarely addressed so far. Therefore, we prepared Mo-10Nb composite powders by mechanical alloying (MA), and investigated the effects of the experimental parameters such as the milling speed and duration on the particle morphology, size distribution, compositional homogeneity, crystallite size, inner strain, and oxygen content. High-quality Mo-10Nb composite powders with 3-μm spherical particles of narrow size distribution, homogeneous elemental distribution, and nanometric crystalline structure were obtained by implementing optimum MA parameters, viz., a milling speed of 250 rpm and duration of 36 h using an MITR QM-QX-4L omnidirectional ball mill. The mechanically alloyed Mo-10Nb composite powders were prone to oxidation when exposed to air, which led to a sharp increase in the oxygen content to ~5400 ppm. X-ray photoelectron spectroscopic analysis revealed the presence of Nb2O5, MoO2, and MoO3 on the surface of the Mo-10Nb particle. We believe that this study demonstrates an interesting strategy for the fabrication of high-quality Mo-10Nb targets. 相似文献