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1.
Micromachines (Basel) ; 13(4)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35457898

RESUMO

An effective System-on-Chip (SoC) for smart Quality-of-Service (QoS) management over a virtual local area network (LAN) is presented in this study. The SoC is implemented by field programmable gate array (FPGA) for accelerating the delivery quality prediction for a service. The quality prediction is carried out by the general regression neural network (GRNN) algorithm based on a time-varying profile consisting of the past delivery records of the service. A novel record replacement algorithm is presented to update the profile, so that the bandwidth usage of the service can be effectively tracked by GRNN. Experimental results show that the SoC provides self-aware QoS management with low computation costs for applications over virtual LAN.

2.
Light Sci Appl ; 9: 83, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411368

RESUMO

Micro-light-emitting diodes (µ-LEDs) are regarded as the cornerstone of next-generation display technology to meet the personalised demands of advanced applications, such as mobile phones, wearable watches, virtual/augmented reality, micro-projectors and ultrahigh-definition TVs. However, as the LED chip size shrinks to below 20 µm, conventional phosphor colour conversion cannot present sufficient luminance and yield to support high-resolution displays due to the low absorption cross-section. The emergence of quantum dot (QD) materials is expected to fill this gap due to their remarkable photoluminescence, narrow bandwidth emission, colour tuneability, high quantum yield and nanoscale size, providing a powerful full-colour solution for µ-LED displays. Here, we comprehensively review the latest progress concerning the implementation of µ-LEDs and QDs in display technology, including µ-LED design and fabrication, large-scale µ-LED transfer and QD full-colour strategy. Outlooks on QD stability, patterning and deposition and challenges of µ-LED displays are also provided. Finally, we discuss the advanced applications of QD-based µ-LED displays, showing the bright future of this technology.

3.
Adv Sci (Weinh) ; 6(24): 1902230, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31871872

RESUMO

Perovskite quantum dots (PQDs) are a competitive candidate for next-generation display technologies as a result of their superior photoluminescence, narrow emission, high quantum yield, and color tunability. However, due to poor thermal resistance and instability under high energy radiation, most PQD-based white light-emitting diodes (LEDs) show only modest luminous efficiency of ≈50 lm W-1 and a short lifetime of <100 h. In this study, by incorporating cellulose nanocrystals, a new type of QD film is fabricated: CH3NH3PbBr3 PQD paper that features 91% optical absorption, intense green light emission (518 nm), and excellent stability attributed to the complexation effect between the nanocellulose and PQDs. The PQD paper is combined with red K2SiF6:Mn4+ phosphor and blue GaN LED chips to fabricate a high-performance white LED demonstrating ultrahigh luminous efficiency (124 lm W-1), wide color gamut (123% of National Television System Committee), and long operation lifetime (240 h), which paves the way for advanced lighting technology.

4.
Adv Mater ; 30(28): e1705385, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29806141

RESUMO

Transforming thermal energy into electric energy and vice versa needs the decoupling of electrical transport from thermal transport. An innovative strategy is proposed by forming/disrupting electrically triggered conductive nanofilaments within semiconducting thin films to switch thermoelectric properties between two states without further material modification and manufacturing processes. It can also controllably adjust the degree of decoupling, providing a potential resolution and performance adjustability for heat/coldness control or power consumption reduction on demand.

5.
Nanoscale ; 8(11): 5954-8, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26924069

RESUMO

We report Raman scattering results for high-quality wurtzite ZnS nanobelts (NBs) grown by chemical vapor deposition. In the Raman spectrum, the ensembles of ZnS NBs exhibit first order phonon modes at 274 cm(-1) and 350 cm(-1), corresponding to A1/E1 transverse optical and A1/E1 longitudinal optical phonons, in addition to a strong surface optical (SO) phonon mode at 329 cm(-1). The existence of the SO band is confirmed by its shift with different surrounding dielectric media. Polarization dependent Raman spectra were recorded on a single ZnS NB and for the first time a SO phonon band has been detected on a single nanobelt. Different selection rules for the SO phonon mode are shown from their corresponding E1/A1 phonon modes, and were attributed to the breaking of anisotropic translational symmetry on the NB surface.

6.
Sci Rep ; 5: 15087, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26455819

RESUMO

A fully transparent resistive memory (TRRAM) based on Hafnium oxide (HfO2) with excellent transparency, resistive switching capability, and environmental stability is demonstrated. The retention time measured at 85 °C is over 3 × 10(4) sec, and no significant degradation is observed in 130 cycling test. Compared with ZnO TRRAM, HfO2 TRRAM shows reliable performance under harsh conditions, such as high oxygen partial pressure, high moisture (relative humidity = 90% at 85 °C), corrosive agent exposure, and proton irradiation. Moreover, HfO2 TRRAM fabricated in cross-bar array structures manifests the feasibility of future high density memory applications. These findings not only pave the way for future TRRAM design, but also demonstrate the promising applicability of HfO2 TRRAM for harsh environments.

7.
Breast J ; 18(4): 351-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22616636

RESUMO

Tissue expander breast reconstruction is a common post mastectomy breast procedure performed by plastic surgeons. The purpose of this study was to define the incidence of breast reconstruction prosthetic infection, relate patient characteristics with increased rate of infection, and analyze the influence of postoperative complications to expander/implant infection. A retrospective, single-institution chart review of 195 women with post mastectomy tissue expander/implant reconstructions performed from 2006 through 2008 was conducted. Total periprosthetic infection rate was calculated. Patient factors, operative technique, and noninfectious complications were analyzed and related to increased periprosthetic infection rate. A binary logistic regression model was fitted using periprosthetic infection as the dependent variable and 12 patient characteristics as independent variables, followed by a step-wise model for best fit with a limited number of independent variables. The overall periprosthetic infection rate per patient over the 2 year period was 5.1%. The incidence of periprosthetic infection per reconstructed breast was 3.2%. Odds ratio estimates indicated that the presence of cellulitis increased the odds of periprosthetic infection more than 200 times (p = <0.0001), and inpatient procedures increased the odds 16 times (p = 0.02). Other variables (i.e., age > 65, DM, flap necrosis, smoking, dehiscence, AlloDerm, etc) failed to reach statistical significance (p > 0.05). Postoperative breast cellulitis and inpatient status appear to be significant risk factors for increased periprosthetic infection. No significant increase in periprosthetic infection rate was noted with other variables in this model.


Assuntos
Mamoplastia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Infecções Relacionadas à Prótese/etiologia , Infecção da Ferida Cirúrgica/etiologia , Expansão de Tecido/efeitos adversos , Adulto , Idoso , Neoplasias da Mama/cirurgia , Feminino , Humanos , Modelos Logísticos , Mamoplastia/métodos , Mastectomia/efeitos adversos , Pessoa de Meia-Idade , Necrose , Razão de Chances , Complicações Pós-Operatórias/epidemiologia , Infecções Relacionadas à Prótese/epidemiologia , Estudos Retrospectivos , Fumar , Retalhos Cirúrgicos/patologia , Infecção da Ferida Cirúrgica/epidemiologia , Expansão de Tecido/métodos , Dispositivos para Expansão de Tecidos
8.
Chest ; 122(6): 2146-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12475859

RESUMO

OBJECTIVES: Although uncommon, prolonged postoperative air leaks are a troublesome complication of lung surgery. This study was performed to determine if buttressing pulmonary staple lines would reduce air leakage at varying airway pressures, and if there was a difference between buttressing materials. METHODS: Using cadaver lungs, the development of air leak from staple lines was evaluated at incremental airway pressures. Unreinforced staples were compared to staples reinforced with bovine pericardium and staples reinforced with expanded polytetrafluorethylene (ePTFE). RESULTS: Unreinforced staple lines began to leak air at an airway pressure of 20 mm Hg, and > 90% leaked at a pressure of 35 mm Hg. Both bovine pericardium and ePTFE significantly reduced the incidence of air leak at these airway pressures. At higher airway pressures, ePTFE was superior to bovine pericardium. CONCLUSION: Staple line reinforcement with either material protects against air leak. Patients at risk for elevated airway pressures and/or postoperative ventilator support should be considered for utilization of these staple reinforcing materials.


Assuntos
Pulmão/cirurgia , Suturas , Adulto , Ar , Humanos , Pericárdio , Politetrafluoretileno/farmacologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle
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