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1.
Appl Ergon ; 106: 103870, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35988302

RESUMO

Future visions of transport systems include both a drive towards automated vehicles and the need for sustainable, active, modes of travel. The combination of these requirements needs careful consideration to ensure the integration of automated vehicles does not compromise vulnerable road users. Transport networks need to be resilient to automation integration, which requires foresight of possible challenges in their interaction with other road users. Focusing on a cyclist overtake scenario, the application of operator event sequence diagrams and a predictive systems failure method provide a novel way to analyse resilience. The approach offers the opportunity to review how automation can be positively integrated into road transportation to overcome the shortfalls of the current system by targeting organisational, procedural, equipment and training measures.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Automação , Meios de Transporte , Viagem , Engenharia
2.
J Exp Child Psychol ; 226: 105573, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36332435

RESUMO

Adolescents use social identities and reasoning to make peer inclusion and attribution decisions. School climate plays a role in these decisions. Thus, this study analyzed how school racial climate and STEM (science, technology, engineering, and math) classroom climate were associated with the choices of adolescents (N = 294; Mage = 15.72 years; 52.3 % female; 36.7 % White/European American, 32.9 % Black/African American, 11.2 % Latino/Hispanic [the most common racial/ethnic groups in the schools where data collection took place]) in two tasks: peer inclusion and attribution of ability. On the peer inclusion task, participants were more likely to choose a non-White peer for a STEM activity if they had lower perceptions of stereotyping at school, and they were more likely to choose a female peer if they were female. Participants were more likely to use reasoning based on personal characteristics when choosing a peer, but female participants who chose a female peer were more likely to use reasoning based on gender. On the attribution task, participants were more likely to choose a non-White peer if they perceived greater STEM connectedness, and they were more likely to choose a White or male peer if they had more positive relationships with their STEM teachers. Therefore, students' perceptions of school racial climate relate to adolescents' peer inclusion decisions, and their perceptions of STEM classroom climate relate to adolescents' ability attributions. Schools may need to focus on creating welcoming school and classroom environments as a way to promote equity in STEM.


Assuntos
Engenharia , Tecnologia , Feminino , Masculino , Adolescente , Humanos , Grupos Raciais , Instituições Acadêmicas , Matemática
3.
CBE Life Sci Educ ; 21(4): ar83, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36318310

RESUMO

A systematic review of the literature was conducted to identify course-based undergraduate research experiences (CUREs) in science, technology, engineering, and math (STEM) courses within the years 2000 through 2020. The goals of this review were to 1) create a resource of STEM CUREs identified by their discipline, subdiscipline, and level; 2) determine the activities included in each CURE, particularly the primary components listed in the CURE definition as well as specific science practices we identified as key to scientific reasoning; and 3) identify the next steps needed in CURE creation and implementation. Our review found 242 CURE curricula described in 220 total articles, with most described in biology, although STEM disciplines, including chemistry and biochemistry, have begun to publish CURE curricula as well. We also found that most CUREs include the primary components. However, when we look at the specific science practices essential to scientific reasoning, we found that these are less common in many CUREs and are implemented differently. We encourage CURE authors to consider including these science practices and potentially measuring their impact on student outcomes. The present work provides a summary of the current published CUREs, their disciplines, course levels, primary components, and specific science practices.


Assuntos
Engenharia , Estudantes , Humanos , Engenharia/educação , Currículo , Matemática , Bioquímica/educação
4.
Nat Commun ; 13(1): 6837, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369261

RESUMO

Expanding the talent pipeline of students from underrepresented backgrounds in STEM has been a priority in the United States for decades. However, potential solutions to increase the number of such students in STEM academic pathways, measured using longitudinal randomized controlled trials in real-world contexts, have been limited. Here, we expand on an earlier investigation that reported results from a longitudinal field experiment in which undergraduate female students (N = 150) interested in engineering at college entry were randomly assigned a female peer mentor in engineering, a male peer mentor in engineering, or not assigned a mentor for their first year of college. While an earlier article presented findings from participants' first two years of college, the current article reports the same participants' academic experiences for each year in college through college graduation and one year post-graduation. Compared to the male peer mentor and no mentor condition, having a female peer mentor was associated with a significant improvement in participants' psychological experiences in engineering, aspirations to pursue postgraduate engineering degrees, and emotional well-being. It was also associated with participants' success in securing engineering internships and retention in STEM majors through college graduation. In sum, a low-cost, short peer mentoring intervention demonstrates benefits in promoting female students' success in engineering from college entry, through one-year post-graduation.


Assuntos
Mentores , Grupo Associado , Masculino , Feminino , Humanos , Estados Unidos , Mentores/educação , Mentores/psicologia , Universidades , Estudantes/psicologia , Engenharia/educação
5.
PLoS One ; 17(11): e0276214, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36327281

RESUMO

Micromechanical cracking processes in rocks directly control macro mechanical responses under compressive stresses. Understanding these micro-scale observations has paramount importance in predicting macro-field problems encountered in rock engineering. Here, our study aims to investigate the development of precursory damage zones resulting from microcracking pertinent to macro-scale rock failure. A series of laboratory tests and three-dimensional (3D) numerical experiments are conducted on andesite samples to reveal the characteristics of damage zones in the form of strain fields. Our results from discrete element methodology (DEM) predict that the crack damage threshold (σcd) values are 61.50% and 67.44% of relevant peak stress under two different confining stresses (σ3 = 0.1 MPa and σ3 = 2 MPa), respectively. Our work evaluates the strain fields within the range of the σcd to the peak stress through discrete analysis for both confining stresses. We note that the representative strain field zones of failure are not observed as soon as the σcd is reached. Such localized zones develop approximately 88% of peak stress levels although the confinement value changes the precursory strain localization that appears at similar stress levels. Our results also show that the distinct strain field patterns developed prior to failure control the final size of the macro-damage zone as well as their orientation with respect to the loading direction (e.g 17° and 39°) at the post-failure stage. These findings help to account for many important aspects of precursory strain field analysis in rock mechanics where the damage was rarely quantified subtly.


Assuntos
Engenharia , Estresse Mecânico , Pressão
6.
Bioinspir Biomim ; 18(1)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36351300

RESUMO

As miscellaneous as the Plant Kingdom is, correspondingly diverse are the opportunities for taking inspiration from plants for innovations in science and engineering. Especially in robotics, properties like growth, adaptation to environments, ingenious materials, sustainability, and energy-effectiveness of plants provide an extremely rich source of inspiration to develop new technologies-and many of them are still in the beginning of being discovered. In the last decade, researchers have begun to reproduce complex plant functions leading to functionality that goes far beyond conventional robotics and this includes sustainability, resource saving, and eco-friendliness. This perspective drawn by specialists in different related disciplines provides a snapshot from the last decade of research in the field and draws conclusions on the current challenges, unanswered questions on plant functions, plant-inspired robots, bioinspired materials, and plant-hybrid systems looking ahead to the future of these research fields.


Assuntos
Materiais Biomiméticos , Robótica , Plantas , Fenômenos Fisiológicos Vegetais , Engenharia
7.
Sensors (Basel) ; 22(22)2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36433574

RESUMO

The educational framework-Conceive, Design, Implement, and Operate-is part of an international proposal to improve education in the field of engineering, emphasizing how to teach engineering comprehensively, which allows the standardization of skills in professionals as a model for teaching engineering. Moreover, problem-based learning allows students to experiment with challenging situations through cases that simulate natural contexts with their profession. The integration of these two education strategies applied to the Internet of Things (IoT) Education for Industry 4.0 has promoted the generation of teaching challenges. Our education strategy proposes the synergy between laboratory guides and the classroom with the following actions: the content of the topic is presented, followed by the presentation of an issue focused into a realistic context, with practical exercises integrating software and hardware for the deployment of the solution to be reported as a final project. Moreover, undergraduate students in the biomedical engineering area acquired new knowledge about IoT, but at the same time, they may develop skills in the field of programming and structuring different architectures to solve real-world problems. Finally, traditional models of education require new teaching initiatives in the field of biomedical engineering concerning the current challenges and needs of the labor market.


Assuntos
Engenharia , Aprendizagem Baseada em Problemas , Humanos , Aprendizagem Baseada em Problemas/métodos , Engenharia/educação , Engenharia Biomédica , Estudantes , Internet
8.
J Mater Chem B ; 10(46): 9699-9712, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36398681

RESUMO

Irregular porous structures for guided bone regeneration applications have gained increasing attention as they are similar to human bone and more suitable for bone tissue growth. However, pore irregularity as a critical characteristic has been poorly explored. This study proposed a method for parametrically designing porous scaffolds based on a Voronoi tessellation which were manufactured by selective laser sintering (SLS) using the polyamide 12 (PA12) material. The deformation mechanism and energy absorption properties of the prepared Voronoi scaffolds were investigated by quasi-static compression experiments. The results demonstrated that the Voronoi scaffold underwent bending deformation subsequent to transverse expansion under compression, and the Voronoi scaffold simultaneously had been indicated to be effective in improving the carrying capacity and energy absorption performance. Subsequently, computational fluid dynamics (CFD) and cell proliferation tests were introduced to comprehensively assess the influence of the scaffolds on cell growth. CFD analysis showed that the permeability of the surveyed scaffolds is between 3.65 × 10-8 and 12.05 × 10-8 m2 similar to that of natural cancellous bone. The cell test expressed that the scaffold exhibits good cell activity, which can be used to promote cell adhesion and migration with superior potential for development and application.


Assuntos
Osso e Ossos , Engenharia Tecidual , Humanos , Porosidade , Permeabilidade , Engenharia
9.
Proc Natl Acad Sci U S A ; 119(49): e2207754119, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36442126

RESUMO

Millions of people across the world live off-grid not by choice but because they live in rural areas, have low income, and have no political clout. Delivering sustainable energy solutions to such a substantial amount of the world's population requires more than a technological fix; it requires leveraging the knowledge of underserved populations working together with a transdisciplinary team to find holistically derived solutions. Our original research has resulted in an innovative Convergence Framework integrating the fields of engineering, social sciences, and communication, and is based on working together with communities and other stakeholders to address the challenges posed by delivering clean energy solutions. In this paper, we discuss the evolution of this Framework and illustrate how this Framework is being operationalized in our on-going research project, cocreating hybrid renewable energy systems for off-grid communities in the Brazilian Amazon. The research shows how this Framework can address clean energy transitions, strengthen emerging industries at local level, and foster Global North-South scholarly collaborations. We do so by the integration of social science and engineering and by focusing on community engagement, energy justice, and governance for underserved communities. Further, this solution-driven Framework leads to the emergence of unique approaches that advance scientific knowledge, while at the same time addressing community needs.


Assuntos
Sistemas Computacionais , Energia Renovável , Humanos , Engenharia , Tecnologia , Altruísmo
10.
Elife ; 112022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36444975

RESUMO

Concerns about systemic racism at academic and research institutions have increased over the past decade. Here, we investigate data from the National Science Foundation (NSF), a major funder of research in the United States, and find evidence for pervasive racial disparities. In particular, white principal investigators (PIs) are consistently funded at higher rates than most non-white PIs. Funding rates for white PIs have also been increasing relative to annual overall rates with time. Moreover, disparities occur across all disciplinary directorates within the NSF and are greater for research proposals. The distributions of average external review scores also exhibit systematic offsets based on PI race. Similar patterns have been described in other research funding bodies, suggesting that racial disparities are widespread. The prevalence and persistence of these racial disparities in funding have cascading impacts that perpetuate a cumulative advantage to white PIs across all of science, technology, engineering, and mathematics.


Assuntos
Engenharia , Imunoterapia , Racismo Sistêmico
11.
Sci Rep ; 12(1): 20540, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446880

RESUMO

The square root operation is indispensable in a myriad of computational science and engineering applications. Various computational techniques have been devised to approximate its value. In particular, convergence methods employed in this regard are highly affected by the initial approximation of the seed value. Research shows that the provision of an initial approximation with higher accuracy yields fewer additional iterations to calculate the square root. In this article, we propose two novel algorithms. The first one presents a seed generation technique that depends on bit manipulation and whose output is to be used as an initial value in the calculation of square roots. The second one describes a quadrature-based square rooting method that utilizes a rectangle as the plane figure for squaring. We provide error estimation of the former using the vertical parabola equation and employ a suitable lookup table, for the latter, to store needed cosine values. The seed generation approach produces a significant reduction in the number of iterations of up to 84.42% for selected convergence methods. The main advantages of our proposed square rooting algorithm lie in its high accuracy and in its requirement of just a single iteration. Our proposed algorithm also provides for lower computational latency, measured in the number of clock cycles, compared to Newton-Raphson's and Bakhshali's square rooting methods.


Assuntos
Algoritmos , Engenharia
12.
Technol Cult ; 63(4): 1140-1156, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36341611

RESUMO

When COVID-19 prevented scholars from traveling to libraries, archives, and museums, staff at those institutions devised creative strategies for providing remote access to their holdings. This article examines one such initiative launched by the Linda Hall Library of Science, Engineering, and Technology in Kansas City, Missouri. The Library's prioritization of print over archival materials, experience fulfilling document delivery requests, and investments in digitization infrastructure facilitated the transition to a completely virtual fellowship program during the 2021-22 academic year. Although virtual fellowships could not replicate every aspect of in-person residencies, they nonetheless supplied scholars with much-needed funding, research materials, and membership in a scholarly community. Based on the program's initial success, the Library plans to continue offering virtual fellowships to scholars otherwise unable to conduct research on site.


Assuntos
COVID-19 , Bibliotecas Médicas , Humanos , Bolsas de Estudo , Engenharia , Arquivos
15.
Molecules ; 27(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36432047

RESUMO

Waste tissues such as mammalian bone are a valuable source from which to extract hydroxyapatite. Camel bone-based hydroxyapatite (CBHA) was extracted from the femur of camel bones using a defatting and deproteinization procedure. The extracted CBHA was mechanically, chemically, physically, morphologically and structurally characterized. Fourier-Transform Infra-Red (FTIR) spectra, Micro-Raman, and X-ray diffraction analysis confirmed successful extraction of hydroxyapatite. The mechanical properties of the CBHA scaffold were measured using a Universal Instron compression tester. Scanning electron microscopy showed the presence of a characteristic interconnected porous architecture with pore diameter ranging from 50-600 µm and micro-computer tomography (Micro-CT) analysis identified a mean porosity of 73.93. Thermogravimetric analysis showed that the CBHA was stable up to 1000 °C and lost only 1.435% of its weight. Inductively coupled plasma-mass spectrometry (ICP-MS) and Energy-dispersive-X-ray (EDX) analysis demonstrated the presence of significant amounts of calcium and phosphorus and trace ions of sodium, magnesium, zinc, lead and strontium. Following 21 days of incubation in simulated body fluid (SBF), the pH fluctuated between 10-10.45 and a gradual increase in weight loss was observed. In conclusion, the extracted CBHA is a promising material for future use in bone tissue regeneration applications.


Assuntos
Durapatita , Engenharia Tecidual , Animais , Camelus , Osso e Ossos , Engenharia
16.
Nat Commun ; 13(1): 7189, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36424374

RESUMO

MHC restriction, which describes the binding of TCRs from CD4+ T cells to class II MHC proteins and TCRs from CD8+ T cells to class I MHC proteins, is a hallmark of immunology. Seemingly rare TCRs that break this paradigm exist, but mechanistic insight into their behavior is lacking. TIL1383I is a prototypical class-mismatched TCR, cloned from a CD4+ T cell but recognizing the tyrosinase tumor antigen presented by the class I MHC HLA-A2 in a fully functional manner. Here we find that TIL1383I binds this class I target with a highly atypical geometry. Despite unorthodox binding, TCR signaling, antigen specificity, and the ability to use CD8 are maintained. Structurally, a key feature of TIL1383I is an exceptionally long CDR3ß loop that mediates functions that are traditionally performed separately by hypervariable and germline loops in canonical TCR structures. Our findings thus expand the range of known TCR binding geometries compatible with normal function and specificity, provide insight into the determinants of MHC restriction, and may help guide TCR selection and engineering for immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Receptores de Antígenos de Linfócitos T , Membrana Celular , Engenharia , Antígeno HLA-A2/genética
17.
Sci Eng Ethics ; 28(6): 56, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36374398

RESUMO

Following other contributions about the MAX accidents to this journal, this paper explores the role of betrayal and moral injury in safety engineering related to the U.S. federal regulator's role in approving the Boeing 737MAX-a plane involved in two crashes that together killed 346 people. It discusses the tension between humility and hubris when engineers are faced with complex systems that create ambiguity, uncertain judgements, and equivocal test results from unstructured situations. It considers the relationship between moral injury, principled outrage and rebuke when the technology ends up involved in disasters. It examines the corporate backdrop against which calls for enhanced employee voice are typically made, and argues that when engineers need to rely on various protections and moral inducements to 'speak up,' then the ethical essence of engineering-skepticism, testing, checking, and questioning-has already failed.


Assuntos
Traição , Princípios Morais , Humanos , Engenharia , Tecnologia
19.
Brain ; 145(11): 3725-3726, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36412514
20.
Sensors (Basel) ; 22(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36298355

RESUMO

State-dependent resistors, capacitors, and inductors are a common part of many smart engineering solutions, e.g., in MEMS (Micro-Electro-Mechanical Systems) sensors and actuators, Micro/NanoMachines, or biomimetic systems. These memory elements are today modeled as generic and extended memristors (MR), memcapacitors (MC), and meminductors (ML), which are more general versions of classical MR, MC, and ML from the infinite set of the fundamental elements of electrical engineering, known as Higher-Order Elements (HOEs). It turns out that models of many complex phenomena in MEMS cannot be constructed only from classical and state-dependent elements such as R, L, and C, but that other HOEs with generalized behavior should also be used. Thus, in this paper, generic and extended versions of HOEs are introduced, overcoming the existing limitation to MR, MC, and ML elements. The relevant circuit theorems are formulated, which generalize the well-known theorems of classical memory elements, and their application to model complex processes of various physical natures in MEMS is shown.


Assuntos
Sistemas Microeletromecânicos , Biomimética , Engenharia
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