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1.
Micromachines (Basel) ; 14(4)2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37421089

RESUMO

A novel micro saw was fabricated using a combination of photolithography and electroplating techniques, resembling a miniature timing belt with sideways blades. The rotation or oscillation direction of the micro saw is designed to be perpendicular to the cutting direction so that transverse cutting of the bone is attainable to extract a preoperatively planned bone-cartilage donor for osteochondral auto-graft transplantation. The mechanical property of the fabricated micro saw obtained using the nanoindentation test shows that the mechanical properties of the micro saw are almost an order of magnitude higher than bone, which indicates its potential bone-cutting application. To demonstrate the cutting capability of the fabricated micro saw, an in vitro animal bone cutting was performed using a custom test rig consisting of a microcontroller, 3D printer, and other readily available parts.

2.
ISA Trans ; 137: 506-518, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36725412

RESUMO

In the present era, due to increasing power demand and complex power system structures having various load disturbances, a load frequency management (LFM) scheme is indispensable to provide uninterrupted power to consumers. This research deals with a fractional-order proportional derivative - (one + fractional order integrator) (FOPD-(1+FOI)) cascade controller as a novel control structure to ameliorate the execution of automatic generation control (AGC) for the LFM of interconnected power system (PS). The implementation of this controller is uncomplicated, and it joins the output of the FOPD controller to (1+FOI) controller, where area control error and power error are considered in the outer and inner feedback control loops, respectively. A maiden attempt of a wild horse optimizer-assisted FOPD-(1+FOI) cascade controller for AGC of considered interconnected PS has been performed in this work. To benchmark the proposed control scheme, two areas reheat thermal PS with GDB and GRC nonlinearities is chosen as the test bench. A vivid comparative analysis of six state-of-the-art control techniques is performed, and the results reveal the potency of the presented control approach. Eigenvalues-based stability assessment of interconnected PS in conjunction with the proposed controller is also performed. Finally, for the real PS implementation of the presented control architecture a new england IEEE 39 test bus is considered and analyzed.

3.
ISA Trans ; 132: 387-401, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35752477

RESUMO

The study made in this paper has been directed towards a novel load frequency management (LFM) scheme for solar-wind-based standalone micro-grid (SMG). For LFM, this brief deals with the introduction of proportional-integral-derivative with filter - (one plus integral), i.e., PIDF-(1+I) cascade controller. A maiden endeavor has been performed to employ a recently developed black widow optimization algorithm (BWOA) to obtain the supplementary controller parameters. The considered SMG consists of the wind turbine generator, diesel engine generator, solar photovoltaic as distributed generation unit, and flywheel and ultra-capacitor are considered as energy storage systems. Generation rate constraints and governor dead-band type power system's nonlinearities are also included in this study. This work aims to mitigate the effect of mismatch in demand and generation and minimize the change in frequency deviation (CFD). The maximum obtained CFD with the proposed controller is 0.048 Hz, which is entirely satisfactory and under the permissible limit of IEEE standard. A vivid comparative analysis of artificial bee colony and BWOA tuned controllers like conventional PID, PIDF, and PIDF-(1+I) is also performed. Finally, the detailed robustness assessment of the proposed controller with its real-time implementation through the standard New England IEEE 39 test bus system presents the controller's superiority.

4.
J Family Med Prim Care ; 11(6): 2345-2350, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36119275

RESUMO

Background: Bone health is an important requirement for healthy aging. Osteoporosis is an important cause of both mortality and morbidity among older adults. If we can predict the risk of future osteoporosis by cost-effective methods, we can prevent it up to certain level and plan intervention accordingly. That's why the present study aims to estimate the likelihood of osteoporosis in patients attending the outpatient department (OPD) in a selected community health center (CHC). Methods: A cross-sectional study was conducted in a CNC in Siwan, Bihar, India. An equal number of male and female patients were recruited by quota sampling. A semi-structured proforma was prepared for data collection using the Fracture Risk Assessment (FRAX) tool without performing a bone mineral density (BMD) test in order to assess major osteoporotic fractures and risk for hip fractures with other requisite information. Results: The collected data were organized using Microsoft Excel and analyzed using the statistical software SPSS Statistics 20. As data were gleaned and put under different categories, a statistical analysis based on the Chi-square test was carried out, and an ROC (receiver operating characteristic) curve was also drawn for statistical inference of the data gathered. The main findings of our analyses include the following: Approximately 15% males and 30% females in the study sample had a higher risk of osteoporosis and about 9% males and 36% females had a higher risk of hip fracture. Overall, the findings showed a statistically significant association (p < 0.05) between the gender of the participants and the FRAX risk scores for osteoporosis and hip fracture. Conclusion: Previously osteoporosis was thought of as a disease that affected only women; nevertheless, emerging findings show that osteoporosis is not unusual in men. The FRAX tool can be used as a screening tool before going for a BMD test.

5.
Indian Pediatr ; 58 Suppl 1: S23-S27, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34687184

RESUMO

Implementing the nurturing care framework (NCF) for early childhood development (ECD) is essentially multisectoral, requiring coordination amongst all sectors and harmoniously integrating it within the existing contact opportunities in the health sector. This paper discusses the relative strengths, persisting gaps, challenges, and the way forward to implement nurturing care for ECD through the public health system. The vast network of frontline health workers and health facilities; community, home, and center-based service delivery; health and wellness centers located close to the communities have the potential to promote nurturing care. Persisting gaps include limited capacities of health workers in the nurturing care domains, lack of community engagement for ECD, weak referral linkages, inability to reach the most vulnerable children, missed opportunities for early identification of children at risk, and early intervention for children developmental delays and difficulties. Moving forward, incorporating nurturing care components into essential services packages, enhancing competencies of health workers, engaging with parents, establishing a mechanism for tracking children at risk, and developmental surveillance by trained service providers can provide the much-needed impetus to ECD.


Assuntos
Desenvolvimento Infantil , Saúde Pública , Criança , Pré-Escolar , Atenção à Saúde , Deficiências do Desenvolvimento , Humanos , Índia
6.
Sci Rep ; 11(1): 18213, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521866

RESUMO

With the spread of COVID-19, significant emphasis has been placed on mitigation techniques such as mask wearing to slow infectious disease transmission. Widespread use of face coverings has revealed challenges such as mask contamination and waste, presenting an opportunity to improve the current technologies. In response, we have developed the Auto-sanitizing Retractable Mask Optimized for Reusability (ARMOR). ARMOR is a novel, reusable face covering that can be quickly disinfected using an array of ultraviolet C lamps contained within a wearable case. A nanomembrane UVC sensor was used to quantify the intensity of germicidal radiation at 18 different locations on the face covering and determine the necessary exposure time to inactivate SARS-CoV-2 in addition to other viruses and bacteria. After experimentation, it was found that ARMOR successfully provided germicidal radiation to all areas of the mask and will inactivate SARS-CoV-2 in approximately 180 s, H1N1 Influenza in 130 s, and Mycobacterium tuberculosis in 113 s, proving that this design is effective at eliminating a variety of pathogens and can serve as an alternative to traditional waste-producing disposable face masks. The accessibility, ease of use, and speed of sanitization supports the wide application of ARMOR in both clinical and public settings.


Assuntos
Desinfecção/métodos , Máscaras , COVID-19/prevenção & controle , COVID-19/virologia , Desinfecção/instrumentação , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos da radiação , Mycobacterium tuberculosis/efeitos da radiação , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/efeitos da radiação , Raios Ultravioleta
7.
Micromachines (Basel) ; 13(1)2021 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-35056191

RESUMO

A layer of self-assembled 1-octadecanethiol was used to fabricate a palladium (Pd)/zinc oxide (ZnO) nanoparticle-based flexible hydrogen sensor with enhanced response and high selectivity at room temperature. A palladium film was first deposited using DC sputtering technique and later annealed to form palladium nanoparticles. The formation of uniform, surfactant-free palladium nanoparticles contributed to improved sensor response towards hydrogen gas at room temperature. The obtained sensor response was higher than for previously reported room temperature Pd/ZnO sensors. Furthermore, the use of the polymer membrane suppressed the sensor's response to methane, moisture, ethanol, and acetone, resulting in the selective detection of hydrogen in the presence of the common interfering species. This study shows a viable low-cost fabrication pathway for highly selective room temperature flexible hydrogen sensors for hydrogen-powered vehicles and other clean energy applications.

8.
ISA Trans ; 112: 234-250, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33303227

RESUMO

The design and control of an intelligent integrated standalone micro-grid (I-ISMG) have been proposed in this study. The ISMG system consists of solar photovoltaic (SPV), wind turbine generator (WTG), diesel engine generator (DEG) as distributed power generation (PG), and battery and flywheel as energy storage systems (ESSs). An improved incremental conductance (I-InC) maximum power point (MPP) tracking (MPPT) scheme, and a fuzzy wind power generation model (FWPGM) are utilized to obtain the power from solar, and wind energy systems respectively. The key contribution of this work is to control the power flow for synchronous micro-grid (MG) operation, which in turn resolves the problem of load frequency control (LFC). In this control strategy, an intelligent, i.e. fuzzy logic-based adaptive control scheme is proposed for the coordinated power flow among the generation, demand, and storage system. To minimize the frequency deviation (Δf) and control of PG from WTG and DEG, frequency support (FS) fuzzy logic-based droop characteristic is employed. For the droop control in WTG and DEG, fuzzy logic-based proportional-integral-derivative (F-PID), and self-tuned-fuzzy PID (STF-PID) control schemes are utilized respectively. Apart from droop controls, a fuzzy observer (FO) is designed to manage power flow to/from the storage systems. Further, the proposed control scheme has been benchmarked using single area power system (SAPS) and modified New England IEEE 39 bus system.

9.
Micromachines (Basel) ; 11(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244636

RESUMO

Flexible sensors with low fabrication cost, high sensitivity, and good stability are essential for the development of smart devices for wearable electronics, soft robotics, and electronic skins. Herein, we report a nanocomposite material based on carbon nanotube and metal oxide semiconductor for ultraviolet (UV) sensing applications, and its sensing behavior. The sensors were prepared by a screen-printing process under a low-temperature curing condition. The formation of a conducting string node and a sensing node could enhance a UV sensing response, which could be attributed to the uniform mixing of functionalized multi-walled carbon nanotubes and zinc oxide nanoparticles. A fabricated device has shown a fast response time of 1.2 s and a high recovery time of 0.8 s with good mechanical stability.

10.
Micromachines (Basel) ; 10(8)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370277

RESUMO

A novel bismuth (Bi)-biopolymer (chitosan) nanocomposite screen-printed carbon electrode was developed using a Bi and chitosan co-electrodepositing technique for detecting multiple heavy metal ions. The developed sensor was fabricated with environmentally benign materials and processes. In real wastewater, heavy metal detection was evaluated by the developed sensor using square wave anodic stripping voltammetry (SWASV). The nanocomposite sensor showed the detection limit of 0.1 ppb Zn2+, 0.1 ppb Cd2+ and 0.2 ppb Pb2+ in stock solutions. The improved sensitivity of the Bi-chitosan nanocomposite sensor over previously reported Bi nanocomposite sensors was attributed to the role of chitosan. When used for real wastewater samples collected from a mining site and soil leachate, similar detection limit values with 0.4 ppb Cd2+ and 0.3 ppb Pb2+ were obtained with relative standard deviations (RSD) ranging from 1.3% to 5.6% (n = 8). Temperature changes (4 and 23 °C) showed no significant impact on sensor performance. Although Zn2+ in stock solutions was well measured by the sensor, the interference observed while detecting Zn2+ in the presence of Cu2+ was possibly due to the presence of Cu-Zn intermetallic species in mining wastewater. Overall, the developed sensor has the capability of monitoring multiple heavy metals in contaminated water samples without the need for complicated sample preparation or transportation of samples to a laboratory.

11.
ACS Appl Mater Interfaces ; 8(48): 33280-33288, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27762558

RESUMO

This work presents a hitherto unreported approach to assemble a 1D oxide-1D chalcogenide heterostructured photoactive film. As a representative system, bismuth (Bi) catalyzed 1D CdSe nanowires are directly grown on anodized 1D TiO2 nanotube (T_NT). A combination of the reductive successive-ionic-layer-adsorption-reaction (R-SILAR) and the solution-liquid-solid (S-L-S) approach is implemented to fabricate this heterostructured assembly, reported in this 1D/1D form for the first time. XRD, SEM, HRTEM, and elemental mapping are performed to systematically characterize the deposition of bismuth on T_NT and the growth of CdSe nanowires leading to the evolution of the 1D/1D heterostructure. The resulting "treelike" photoactive architecture demonstrates UV-visible light-driven electron-hole pair generation. The photoelectrochemical results highlight: (i) the formation of a stable n-n heterojunction between TiO2 nanotube and CdSe nanowire, (ii) an excellent correlation between the absorbance vis-à-vis light conversion efficiency (IPCE), and (iii) a photocurrent density of 3.84 mA/cm2. This proof-of-concept features the viability of the approach for designing such complex 1D/1D oxide-chalcogenide heterostructures that can be of interest to photovoltaics, photocatalysis, environmental remediation, and sensing.

12.
ACS Appl Mater Interfaces ; 8(21): 13400-9, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27121182

RESUMO

The assembly of a large-bandgap one-dimensional (1D) oxide-conductive carbon-chalcogenide nanocomposite and its surface, optical, and photoelectrochemical properties are presented. Microscopy, surface analysis, and optical spectroscopy results are reported to provide insights into the assembly of the nanostructure. We have investigated (i) how the various carbon allotropes (C60), reduced graphene oxide (RGO), carbon nanotubes (CNTs), and graphene quantum dots (GQDs) can be integrated at the interface of the 1D TiO2 and zero-dimensional (0D) CdS nanocrystals; (ii) the carbon allotrope and CdS loading effects; (iii) the impact of the carbon allotrope presence on 0D CdS nanocrystals; and (iv) how they promote light absorbance. Subsequently, the functioning of the integrated nanostructured assembly in a photoelectrochemical cell has been systematically investigated. These studies include (i) chronoamperometry, (ii) impedance measurements or EIS, and (iii) linear sweep voltammetry. The results indicate that the presence of a GQD interface shows the most enhancement in the photoelectrochemical properties. The optimized photocurrent values were respectively noted to be 2.8, 2.2, 1.9, and 1.6 mA/cm(2), indicating JGQD > JRGO > JCNT > Jfullerene. Furthermore, the annealing conditions have indicated that ammonia treatment leads to an increase in the photoelectrochemical responses when using any form of the carbon allotropes.

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