Is it suitable to use the same categorization in rating scales when applied to students with distinctive levels of achievement?

This study examined the efficiency of using the same rating scale categories in measuring affective constructs for students with distinctive levels of achievement. Data used in this study came from the Trends in Mathematics and Science Study (TIMSS) 2011, as a case, on the three scales that were designed to measure eighth graders\u27 attitudes towards science. Data from the four higher and the four lower science performing countries were analyzed using Rasch model. Results revealed that the use of a four-point rating scale appears to be appropriate for some of the higher performing countries; however, it was not appropriate for the lower performing countries. In addition, category functioning and distances between threshold estimates differed by whether the country was a higher or a lower performing country; distances between threshold estimates were too close for the lower performing countries as compared to the higher performing countries. The findings of the current study question the utility of using these scales for a cross-national sample and deducing results concerning the samples’ agreeability to the construct of attitudes towards science

Growth of n-ZnOnanorods on p-GaN using an Aqueous Solution Method

Wide band gap semiconductors like GaN and ZnO have high electron mobility and wide band gap energy. Zinc oxide (ZnO)nanorod arrays are grown on a seed-layer ZnO/GaN l sapphire substrate using a wet chemical bath deposition method. Chemical solution deposition is a low-temperature and possibly the lowest-cost method of growing ZnOnanorods on a GaN substrate. Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) measurements were used to examine the morphology, phase growth orientation and the structure of the ZnOnanorods and the GaN thin film. Optical property of the as-grown ZnOnanorodsand the GaN thin film was analyzed by room temperature photoluminescence measurements. The synthesis of vertically well-aligned nZnOnanorods on p-GaN film with large aspect ratio, high optical quality, and high density can be very useful for fabricating nanoelectronic and nano-optical devices

Near Ultra-Violet Electroluminescence from a ZnO Nanorods/p-GaN Heterojunction Light Emitting Diode

The heterostructure of the n-ZnO nanorod (NRs) arrays grown on the p-GaN layer was formed using lowcost hydrothermal technique in order to fabricate a light emitting diode (LED) device. Morphological, structural and optica l properties of as-prepared sample are described. The LED exhibited room temperature current-voltage (1-V) characteristics confirming a rectifying diode behaviour. The device presents near ultra-violet (UV) color under reverse bias. The electroluminescence (EL) spectrum of color emitting LED composed of intense peaks centered at 378 nm and 367 nm. The electroluminescence mechanism of the heterojunction LED was discussed in terms of band diagram

pH Sensing Characteristics of CuS/ZnO Thin Film Implemented as EGFET

Copper sulphide (CuS) is one of the most important semiconductor materials used in many applications for its semiconducting characteristics. CuS nanoscale thin films were deposited on various substrates using various methods of deposition; recently CuS thin films were used as extended gate field effect transistor (EGFET) and implemented as a pH sensor. In this work, CuS thin film was deposited on ZnO layer using spray pyrolysis deposition (SPD). CuS solution (0.4 M) was prepared from copper(II) chloride and sodium thiosulfate dissolved in deionised water. the precursors used to prepare CuS solution were copper chloride and sodium thiosulfate with 0.4 M concentration, and these precursors were solved using deionized water. The structural characteristics of this thin film show two phases for CuS; covellite and chalcocite with grain size of 31.2 nm. Nanoplate structure with a lot of aggregations was achieved from this deposition and it is confirmed by morphological examination, which estimates the roughness of the film to be 0.145 μm. CuS/ZnO thin film was used as EGFET and applied as pH sensor; the sensitivity and hysteresis were measured for this sensor to be 23.3 mV/pH and 17.5 mV, respectively

ZnO Nanostructures Assisted Growth By Different NH4F Concentrations For Potential Photovoltaic Applications

In this study, different morphologies of ZnO nanostructures (NSs) were synthesized by adding ammonium fluoride (NH4F) at different concentrations using the chemical bath deposition (CBD) method for exploration of photovoltaic applications. Morphology varies from well aligned hexagonal nanorods (NRs), to nanotetrods (NTs) and nanoflowers (NFs) as observed and revealed by field emission scanning microscopy (FESEM). X-ray diffraction spectrum (XRD) analysis confirmed good crystal quality of ZnO nanostructures (NSs) along (002). Ultraviolet-visible (UV-Vis) analysis confirms strong reflection suppression in the ultraviolet-near infrared (UV-NIR) range, giving a high green signal for solar cell applications. Finally, photoluminescence (PL) emission has shown both strong near band edge (NBE) and deep level emission (DLE) peaks indicating a promising signal for different applications such as for photo sensors and photo catalytic

ZnO Nanostructures Assisted Growth By Different NH4F Concentrations For Potential Photovoltaic Applications

In this study, different morphologies of ZnO nanostructures (NSs) were synthesized by adding ammonium fluoride (NH4F) at different concentrations using the chemical bath deposition (CBD) method for exploration of photovoltaic applications. Morphology varies from well aligned hexagonal nanorods (NRs), to nanotetrods (NTs) and nanoflowers (NFs) as observed and revealed by field emission scanning microscopy (FESEM). X-ray diffraction spectrum (XRD) analysis confirmed good crystal quality of ZnO nanostructures (NSs) along (002). Ultraviolet-visible (UV-Vis) analysis confirms strong reflection suppression in the ultraviolet-near infrared (UV-NIR) range, giving a high green signal for solar cell applications. Finally, photoluminescence (PL) emission has shown both strong near band edge (NBE) and deep level emission (DLE) peaks indicating a promising signal for different applications such as for photo sensors and photo catalytic

Comparison Study Of Hydrothermally Grown ZnO Nanorods On Untreated Silicon And Black Silicon Substrates

In this paper, the morphological, structural and optical properties of ZnO nanorods grown using the hydrothermal method was studied on two different substrates: untreated silicon and black silicon. Prior to hydrothermal growth, ZnO seed layer was deposited onto the substrates using radio-frequency (RF) sputtering. FESEM imaging was conducted to study the morphology of ZnO nanostructures grown on the substrates. AFM testing was done to determine the surface roughness of both samples. X-Ray diffraction (XRD) and photoluminescence (PL) spectra are obtained to determine the structural and optical properties of ZnO nanostructures. Diffuse reflectance spectra (DRS) was also obtained to determine the ZnO band gap using the Kubelka-Munk theory

ICoFM 2016-58: Influence of Solution Deposition Rate on Properties of V2O5 Thin Films Deposited by spray Pyrolysis Technique

Vanadium oxide (V2O5) thin films were deposited on glass substrates by using a cost-efficient spray pyrolysis technique. The film were grown at 350°C through thermal decomposition VCI3 in deionized water with different solution spray rates. The high resolution X-ray diffraction result revealed the formation of nanocrystalline films having orthorhombic structures with preferential orientation along (101) direction. The spray rate influenced surface morphology and crystallite size of films. The crystallite size was found to increase whereas the micro-strain was decreased by increasing the spray deposition rates. The increase in crystallite size and decrease in the macrostrain resulted in an improvement in the films crystallinity. The UV-Visible spectroscopy analysis indicated that the average transmittance of all films lies in the range 75-80%. The band gap of V2O5 film was decreased from 2.65 to 2.46 eV with increase of the spray deposition rate from 5 ml/min to 10 ml/min

Enhancing smart home energy efficiency through accurate load prediction using deep convolutional neural networks

The method of predicting the electricity load of a home using deep learning techniques is called intelligent home load prediction based on deep convolutional neural networks. This method uses convolutional neural networks to analyze data from various sources such as weather, time of day, and other factors to accurately predict the electricity load of a home. The purpose of this method is to help optimize energy usage and reduce energy costs. The article proposes a deep learning-based approach for nonpermanent residential electrical energy load forecasting that employs temporal convolutional networks (TCN) to model historic load collection with timeseries traits and to study notably dynamic patterns of variants amongst attribute parameters of electrical energy consumption. The method considers the timeseries homes of the information and offers parallelization of large-scale facts processing with magnificent operational efficiency, considering the timeseries aspects of the information and the problematic inherent correlations between variables. The exams have been done using the UCI public dataset, and the experimental findings validate the method's efficacy, which has clear, sensible implications for setting up intelligent strength grid dispatching

Encapsulation Of Ag Nanoparticle-Carbon Composite And Enhancement Of Visible Light ZnO Nanorods Photodiode

In this paper, the effect of encapsulating silver nanoparticles (Ag NPs)- carbon composite onto zinc oxide (ZnO) nanorods (NRs) hydrothermally grown on silicon substrate is characterized and its photodiode performance studied. The composite was dissolved in acetone and drop casted onto ZnO NRs and the samples are baked on a hot plate. FESEM imaging was done and shows the top part of ZnO NRs coated with the composite and EDX testing shows the component are made of carbon as the majority and Ag the minority component. Transmission electron microscopy (TEM) shows the Ag-NPs embedded into the carbon coating. Photoluminescence (PL) spectra shows slight peak broadening of the ZnO main peak at 378 nm. Photodiode measurements shows the encapsulated nanorods has reduced photoresponse to UV light (395 nm) but more responsive to visible light (460 nm) due to creation of new energy states inside the band gap of ZnO