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3.
PLoS One ; 16(12): e0261250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34914786

RESUMO

Many fundamental problems in data mining can be reduced to one or more NP-hard combinatorial optimization problems. Recent advances in novel technologies such as quantum and quantum-inspired hardware promise a substantial speedup for solving these problems compared to when using general purpose computers but often require the problem to be modeled in a special form, such as an Ising or quadratic unconstrained binary optimization (QUBO) model, in order to take advantage of these devices. In this work, we focus on the important binary matrix factorization (BMF) problem which has many applications in data mining. We propose two QUBO formulations for BMF. We show how clustering constraints can easily be incorporated into these formulations. The special purpose hardware we consider is limited in the number of variables it can handle which presents a challenge when factorizing large matrices. We propose a sampling based approach to overcome this challenge, allowing us to factorize large rectangular matrices. In addition to these methods, we also propose a simple baseline algorithm which outperforms our more sophisticated methods in a few situations. We run experiments on the Fujitsu Digital Annealer, a quantum-inspired complementary metal-oxide-semiconductor (CMOS) annealer, on both synthetic and real data, including gene expression data. These experiments show that our approach is able to produce more accurate BMFs than competing methods.


Assuntos
Mineração de Dados/métodos , Algoritmos , Análise por Conglomerados , Computadores/tendências , Modelos Teóricos
4.
ScientificWorldJournal ; 2021: 3384332, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650344

RESUMO

BACKGROUND: In this globalized and high-tech era, the computer has become an integral part of daily life. A constant use of computer for 3 hours and more per day can cause computer vision syndrome (CVS), which is one of the leading occupational hazards of the 21st century. The visual difficulties are the most common health problems associated with excessive computer use. Therefore, this study aimed to assess the prevalence and associated factors of CVS among instructors working in Ethiopian universities. METHODS: A web-based cross-sectional study was conducted among 422 university instructors in Ethiopia from February 02 to March 24, 2021. A structured and self-administered questionnaire prepared by Google Forms was shared among instructors through their e-mail addresses, Facebook, and Telegram accounts. Data cleanup and cross-checking were done before analysis using SPSS version 23. A multivariable logistic regression was applied to identify factors associated with CVS using p value <0.05 and 95% confidence interval. RESULTS: Of the total 416 participants, about 293 (70.4%) were reported to have CVS (95% CI: 65.9-74.5%), of which 54.6% were aged 24-33 years. Blurred vision, pain in and around the eye, and eye redness were the main symptoms reported. Working in third-established universities (AOR = 8.44, 95% CI: 5.47-21.45), being female (AOR = 2.69, 95% CI: 1.28-5.64), being 44 years old and above (AOR = 2.73, 95% CI: 1.31-5.70), frequently working on the computer (AOR = 5.51, 95% CI: 2.05-14.81), and sitting in bent back position (AOR = 8.10, 95% CI: 2.42-23.45) were the factors associated with computer vision syndrome. CONCLUSIONS: In this study, nearly seven-tenths of instructors in Ethiopian universities reported having symptoms of computer vision syndrome. Working in third-generation universities, being female, age, frequently working on the computer, and sitting in bent back position were statistically significant predictors in computer vision syndrome. Therefore, optimizing exposure time, addressing ergonomic hazards associated with computer usage through on-the-job and off-the-job training, and making the safety guidelines accessible for all university instructors would be critical to address the problem.


Assuntos
Computadores/tendências , Docentes , Internet/tendências , Tempo de Tela , Universidades/tendências , Transtornos da Visão/epidemiologia , Adulto , Estudos Transversais , Etiópia/epidemiologia , Docentes/psicologia , Feminino , Humanos , Masculino , Prevalência , Síndrome , Transtornos da Visão/diagnóstico , Transtornos da Visão/psicologia
5.
PLoS One ; 15(3): e0229645, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32119705

RESUMO

Solid-state drives (SSDs) that do not have internal dynamic random-access memory (DRAM) are being widely spread for client SSD and embedded SSD markets in recent years because they are cheap and consume less power. Obviously, their performance is lower than conventional SSDs because they cannot exploit advantages of DRAM in the controller. However, this problem can be alleviated by using host memory buffer (HMB) feature of Non-Volatile Memory Express (NVMe), which allows SSDs to utilize the DRAM of host. In this paper, we show that commercial DRAM-less SSDs clearly exhibit worse I/O performance than SSDs with internal DRAM, but this can be improved by using the HMB feature. We also present methods that reveal how the host memory buffer is used in commercial DRAM-less SSDs to improve I/O performance. Through extensive experiments, we conclude that DRAM-less SSDs evaluated in this study mainly exploit the host memory buffer as an address mapping table cache rather than a read cache or write buffer to improve I/O performance.


Assuntos
Periféricos de Computador/tendências , Dispositivos de Armazenamento em Computador/tendências , Computadores/tendências , Algoritmos , Periféricos de Computador/economia , Periféricos de Computador/estatística & dados numéricos , Dispositivos de Armazenamento em Computador/estatística & dados numéricos
6.
Nature ; 575(7784): 607-617, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31776490

RESUMO

Guided by brain-like 'spiking' computational frameworks, neuromorphic computing-brain-inspired computing for machine intelligence-promises to realize artificial intelligence while reducing the energy requirements of computing platforms. This interdisciplinary field began with the implementation of silicon circuits for biological neural routines, but has evolved to encompass the hardware implementation of algorithms with spike-based encoding and event-driven representations. Here we provide an overview of the developments in neuromorphic computing for both algorithms and hardware and highlight the fundamentals of learning and hardware frameworks. We discuss the main challenges and the future prospects of neuromorphic computing, with emphasis on algorithm-hardware codesign.


Assuntos
Inteligência Artificial/tendências , Computadores/tendências , Redes Neurais de Computação , Algoritmos , Modelos Neurológicos
8.
Aktuelle Urol ; 50(4): 386-391, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31091542

RESUMO

The Internet has shaped and changed society like no other technology. Culturally, the emergence of the Internet is being described as having the same impact on society as the invention of printing. In 2018, more than 4 billion people had access to the Internet. Among all Internet users, approximately 80 % search the Internet for health-related information, with cancer being the most frequently searched condition. Patients rate the Internet as the second most helpful source of information, outranked only by consultation with a medical doctor. There are more than 2.6 billion active social media users. Among urological residents, 97 % use social media on a regular basis. Digitalisation has the potential to strengthen patients' health literacy and optimise patient care, especially in the oncologic field. In summary, digitalisation bears an enormous potential for the field of urology.


Assuntos
Computadores/tendências , Internet/tendências , Computação em Informática Médica/tendências , Educação de Pacientes como Assunto/tendências , Urologia/tendências , Previsões , Alemanha , Letramento em Saúde , Humanos , Aplicativos Móveis/tendências , Mídias Sociais/tendências , Neoplasias Urológicas/terapia
10.
Methods Mol Biol ; 1897: 17-29, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30539431

RESUMO

Biobanks support medical research by facilitating access to biospecimens. Biospecimens that are linked to clinical and molecular information are particularly useful for translational biomedical research. Tracking and managing the biospecimens and their associated data are therefore crucial tasks in the functioning of a biobank. Adequate computing hardware, efficient and comprehensive biobanking software, and cost-effective data storage are needed for proper management of biospecimens. As biobanks build up extensive stores of specimens and patient data, ethical considerations also inevitably arise. Herein, we describe some basic considerations for establishing a biobanking information technology infrastructure that a beginning biobanker needs. Finally, we also discuss trends and future needs in biobanking informatics.


Assuntos
Bancos de Espécimes Biológicos/tendências , Pesquisa Biomédica , Tecnologia da Informação/tendências , Software/tendências , Computadores/tendências , Humanos
12.
BMC Bioinformatics ; 19(Suppl 18): 485, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30577756

RESUMO

BACKGROUND: Manual extraction of information from electronic pathology (epath) reports to populate the Surveillance, Epidemiology, and End Result (SEER) database is labor intensive. Systematizing the data extraction automatically using machine-learning (ML) and natural language processing (NLP) is desirable to reduce the human labor required to populate the SEER database and to improve the timeliness of the data. This enables scaling up registry efficiency and collection of new data elements. To ensure the integrity, quality, and continuity of the SEER data, the misclassification error of ML and NPL algorithms needs to be negligible. Current algorithms fail to achieve the precision of human experts who can bring additional information in their assessments. Differences in registry format and the desire to develop a common information extraction platform further complicate the ML/NLP tasks. The purpose of our study is to develop triage rules to partially automate registry workflow to improve the precision of the auto-extracted information. RESULTS: This paper presents a mathematical framework to improve the precision of a classifier beyond that of the Bayes classifier by selectively classifying item that are most likely to be correct. This results in a triage rule that only classifies a subset of the item. We characterize the optimal triage rule and demonstrate its usefulness in the problem of classifying cancer site from electronic pathology reports to achieve a desired precision. CONCLUSIONS: From the mathematical formalism, we propose a heuristic estimate for triage rule based on post-processing the soft-max output from standard machine learning algorithms. We show, in test cases, that the triage rule significantly improve the classification accuracy.


Assuntos
Computadores/tendências , Bases de Dados Factuais/tendências , Triagem/métodos , Teorema de Bayes , Humanos , Armazenamento e Recuperação da Informação
13.
PLoS One ; 13(11): e0206259, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30383760

RESUMO

This paper presents a discretization methodology applied to the NBV (Next Best View) problem, which consists of determining the heuristical best position of the next scan. This new methodology is a hybrid process between a homogenous voxelization and an octree structure that preserves the advantages of both methods. An octree structure is not directly applicable to the NBV problem: as the point cloud grows with every successive scanning, the limits and position of the discretization, octree structure must coincide, in order to transfer the information from one scan to the next. This problem is solved by applying a first coarse voxelization, followed by the division of each voxel in an octree structure. In addition, a previous methodology for solving the NBV problem has been adapted to make use of this novel approach. Results show that the new method is three times faster than the homogenous voxelization for a maximum resolution of 0.2m. For this target resolution of 0.2m, the number of voxels/octants in the discretization is reduced approximately by a 400%, from 35.360 to 8.937 for the study case presented.


Assuntos
Computadores/tendências , Robótica/tendências , Algoritmos , Humanos , Lasers , Controle de Qualidade
16.
Rev. psicol. deport ; 27(supl.1): 83-88, 2018.
Artigo em Português | IBECS | ID: ibc-172357

RESUMO

O objetivo principal deste trabalho foi analisar a percepção moral dos atletas adolescentes de futebol em territórios concretos e virtuais. Pesquisa qualitativa elaborada com dados coletados por meio de entrevistas semiestruturadas pelo Facebook envolvendo 14 atletas homens, com idades entre 16 e 18 anos (±17,35), praticantes de futebol em campeonatos oficiais. Depois de tratados pela Análise Temática e de Discurso, os dados indicaram a configuração de um homem modular para três territórios distintos: ambientes cotidiano, esportivo e virtual, que deixam marcas na percepção moral do atleta jovem. Os atletas acreditam estar imunes a valores morais permanentes ao se deslocarem pelas fendas interterritoriais. Suas ações assumem características de um jogo moral relativo, transitório e desvinculado de parâmetros históricos concretos, o que impossibilita perceber a relação intrínseca entre a dimensão prática e a dimensão moral. Verificou-se a composição de um homem/atleta, etiquetado para cada ambiente em que atua; tridimensional e de moral transitória (AU)


El principal objetivo de este trabajo fue analizar la percepción moral de los atletas adolescentes de fútbol en territorios concretos y virtuales. Fue una investigación cualitativa con datos recolectados a través de entrevistas semiestructuradas en la red social Facebook, con la participación de 14 atletas hombres de 16 a 18 años (±17,35) practicantes del fútbol en campeonatos oficiales. Tratados por las Análisis Temático y del Discurso los resultados indicaron la configuración de un hombre modular para tres áreas distintas: el cotidiano, los deportes y los ambientes virtuales, que dejan marcas en la percepción moral del joven atleta. Los atletas creen que son inmunes a los valores morales permanentes desplazando por las fisuras interterritoriales. Sus acciones suponen características de un juego moral relativo, transitorio y desconectado de los parámetros históricos concretos que impide la percepción de la relación intrínseca que hay entre la dimensión práctica y la dimensión moral. Se descubrió el desarrollo de un hombre/atleta calificado para cada entorno en que actúa, impreso tridimensional y com moral transitória (AU)


The aim of this research was to analyze the moral perception of adolescent soccer athletes in virtual and concrete territories. In this qualitative study the data was collected through semi-structured interviews on Facebook, with 14 male athletes, aged between 16 to 18 years (± 17.35) who played soccer in official tournaments. After being treated by the Thematic and Discourse Analysis, the data indicated the configuration of a modular man for three different territories: everyday, sporty and virtual environments which leave marks on the moral perception of the young athlete. Athletes believe they are immune from permanent moral values as they move through inter-territorial gaps. Their actions assume the characteristics of a relative moral game, transitory and disconnected from concrete historical parameters, which makes it impossible to realize the intrinsic relationship between the practical dimension and the moral dimension. This research showed the composition of a man / athlete, labeled for each environment that he acts in, a young man shaped in three-dimensional and transient moral (AU)


Assuntos
Humanos , Masculino , Adolescente , Adulto Jovem , Futebol/psicologia , Atletas/psicologia , Moral , Esportes/psicologia , Tecnologia/métodos , Computadores/tendências , 25783/métodos , Entrevista Psicológica/métodos
17.
Pediatrics ; 140(Suppl 2): S92-S96, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29093040

RESUMO

Given the pervasive use of screen-based media and the high prevalence of insufficient sleep among American youth and teenagers, this brief report summarizes the literature on electronic media and sleep and provides research recommendations. Recent systematic reviews of the literature reveal that the vast majority of studies find an adverse association between screen-based media consumption and sleep health, primarily via delayed bedtimes and reduced total sleep duration. The underlying mechanisms of these associations likely include the following: (1) time displacement (ie, time spent on screens replaces time spent sleeping and other activities); (2) psychological stimulation based on media content; and (3) the effects of light emitted from devices on circadian timing, sleep physiology, and alertness. Much of our current understanding of these processes, however, is limited by cross-sectional, observational, and self-reported data. Further experimental and observational research is needed to elucidate how the digital revolution is altering sleep and circadian rhythms across development (infancy to adulthood) as pathways to poor health, learning, and safety outcomes (eg, obesity, depression, risk-taking).


Assuntos
Desenvolvimento Infantil/fisiologia , Ritmo Circadiano/fisiologia , Computadores/estatística & dados numéricos , Internet/estatística & dados numéricos , Sono/fisiologia , Mídias Sociais/estatística & dados numéricos , Adolescente , Criança , Computadores/tendências , Estudos Transversais , Feminino , Humanos , Estudos Observacionais como Assunto/métodos , Mídias Sociais/tendências
18.
Pediatrics ; 140(Suppl 2): S122-S126, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29093046

RESUMO

In today's global culture and economy, in which individuals have access to information at their fingertips at all times, digital and media literacy are essential to participate in society. But what specific competencies must young citizens acquire? How do these competencies influence pedagogy? How are student knowledge, attitudes, and behaviors changed? What are the best ways to assess students' digital and media literacy? These questions underscore what parents, educators, health professionals, and community leaders need to know to ensure that youth become digitally and media literate. Experimental and pilot programs in the digital and media literacy fields are yielding insights, but gaps in understanding and lack of support for research and development continue to impede growth in these areas. Learning environments no longer depend on seat time in factory-like school settings. Learning happens anywhere, anytime, and productivity in the workplace depends on digital and media literacy. To create the human capital necessary for success and sustainability in a technology-driven world, we must invest in the literacy practices of our youth. In this article, we make recommendations for research and policy priorities.


Assuntos
Compreensão , Alfabetização Digital/tendências , Computadores/estatística & dados numéricos , Computadores/tendências , Aprendizagem , Adolescente , Criança , Humanos
19.
Pediatrics ; 140(Suppl 2): S127-S131, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29093047

RESUMO

Research on the social implications of adolescent technology use often focuses on identifying and preventing risk. However, adolescence is also a time of rapidly expanding capacities, expectations of autonomy, and identity exploration. In this article, we highlight findings from research in the field of youth civic development, which point to the importance of youth civic engagement during adolescence for later adult civic engagement as well as for promoting positive developmental outcomes. Researchers suggest that certain forms of Internet use (such as information seeking, social network site use, media production, and participation in online communities) promote civic engagement and that digital tools play an important role in youth empowerment efforts. In this article, we suggest a need for greater attention to efforts to promote digital media competencies among adolescents and for greater coordination of research on adolescent risk and adolescent autonomy and empowerment related to Internet use.


Assuntos
Comportamento do Adolescente/psicologia , Computadores/tendências , Política , Mídias Sociais/tendências , Responsabilidade Social , Adolescente , Pesquisa Participativa Baseada na Comunidade/métodos , Pesquisa Participativa Baseada na Comunidade/tendências , Humanos , Internet/tendências , Relações Interpessoais
20.
Pediatrics ; 140(Suppl 2): S137-S141, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29093049

RESUMO

Diverse international perspectives show that children can benefit greatly from digital opportunities. Despite widespread optimism about the potential of digital technologies, especially for information and education, the research reveals an insufficient evidence base to guide policy and practice across all continents of the world, especially in middle- and low-income countries. Beyond revealing pressing and sizeable gaps in knowledge, this cross-national review also reveals the importance of understanding local values and practices regarding the use of technologies. This leads us to stress that future researchers must take into account local contexts and existing inequalities and must share best practices internationally so that children can navigate the balance between risks and opportunities. This article documents the particular irony that while the world's poorer countries look to research to find ways to increase access and accelerate the fair distribution of digital educational resources, the world's wealthier countries look to research for guidance in managing excessive screen time, heavily commercial content, and technologies that intrude on autonomy and privacy. We conclude by recommending that digital divides should be carefully bridged with contextual sensitivity to avoid exacerbating existing disparities; that the provision of technological resources is complemented by a focus on skills enhancement, for teachers as well as students; that a keen eye is needed to ensure the balance of children's protection and participation rights, with protection now including data abuses as well as safety considerations; and that we forge collaborations among all stakeholders in seeking to enhance children's digital opportunities worldwide.


Assuntos
Pesquisa Biomédica/tendências , Computadores/tendências , Política de Saúde/tendências , Internacionalidade , Fatores Socioeconômicos , Pesquisa Biomédica/legislação & jurisprudência , Criança , Computadores/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Humanos , Internacionalidade/legislação & jurisprudência
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