Complementary Layer Research Articles

Societal and Structural Risks of Biometric ID: Towards People’s Right to Privacy

This article examines the societal and structural risks linked to digital ID programmes in Africa and the adequacy of regulatory and legislative responses that are in progress in this area. It unpacks the disjointedness between the societal and structural nature of the risks and the individualistic orientation of the right to privacy and data protection often presented as a response to such risks. To address these incongruities, the article argues for people’s right to privacy as a complementary layer of protection to mitigate the societal and structural risks associated with digital ID programmes. The account of people’s privacy proposed in this article draws on the people-centric African perspective on human rights as reflected in the African Charter on Human and People’s Rights (the Banjul Charter), African philosophy that is rooted in communality, scholarships in the area of group privacy, people-centric due diligence assessment, and the AU Data Policy Framework.

Photosystem I enhanced perovskite–Organic tandem solar cell efficiency

Tandem solar cells (TSC) have been introduced to better absorb the spectrum of sunlight and reduce optical loss. Among these, perovskite–organic tandem solar cells (P-OTSC) have emerged as a prominent topic over the last decade due to their complementary absorption spectrum. Additionally, incorporating diverse pigmented protein complexes in TSC fabrication is becoming more common. Natural chlorophyll-containing photosystems have garnered significant attention for their naturally solar-tuned absorption spectra. Photosystem I protein (PSI), is the most robust component of oxygenic photosynthesis and contains over 100 Chl a molecules/complex with two sharp absorbance peaks at 430 and 665 nm. PSI offers a second and complementary active layer because P-OTSCs often have a low extinction coefficient in the red wavelength region. In this research, the performance of P-OTSCs was enhanced by improving the absorption spectrum by utilizing an isolated plant PSI complex. The circuit current density (Jsc) increased from 14.23 mA/cm² to 14.95 mA/cm², and the power conversion efficiency (PCE) of P-OTSCs increased from 19.32 % to 20.24 %. We also observed that the external quantum efficiency (EQE) shows an apparent increase in the long wavelength region, reflecting the absorbance of light by PSI. This work is the first to report the integration of PSI into perovskite–organic tandem solar cells, and it motivates new design considerations that can further boost efficiency and utilize natural, earth-abundant pigment proteins.

The nano-sheet structure adjustment and long-term stability of Zn-doped NiO electrochromic films

NiO is a typical anode electrochromic material based on its excellent electrochemical performance. However excellent cycle stability has always been the most important goal pursued by researchers. This study successfully prepared the complex multi-channel self-assembled nanosheet structure of low concentration and different Zn content doped NiO films with outstanding cycle stability on FTO by the low-temperature hydrothermal method. This excellent cycle stability provides a basis for applying NiO as a complementary layer in electrochromic devices. Zn doping influences the surface microstructure and electrochromic properties of NiO films. It is worth noting that all samples show large modulation amplitude, high coloring efficiency, and fast response time at the wavelength of 550 nm. The samples doped with 1% Zn exhibited more outstanding electrochromic properties than the samples without Zn doping, including fast switching speed (6.4 s and 3.8 s), significantly high coloration efficiency (52.49 cm2·C−1), transmittance modulation (68.57 % at 550 nm), and especially outstanding cycle stability (99.47 % after 5000 cycles). Zn doping affects the microstructure of the film surface, which greatly improves the cycle stability of the film by combining doping and structure control. We consider that the 1 % Zn-doped sample has the best cyclic stability because of the lower interface barrier between the 1 % Zn-doped sample and the FTO, the Zn-doped film forms a complex multi-channel structure, and the coupling effect makes the sample more conducive to the charge entry and exit.

The detection of Japanese encephalitis virus in municipal wastewater during an acute disease outbreak.

To demonstrate the capability of wastewater-based surveillance (WBS) as a tool for detecting potential cases of Japanese Encephalitis Virus (JEV) infection in the community. In this study, we explore the potential of WBS to detect cases of JEV infection by leveraging from an established SARS-CoV-2 wastewater surveillance program. We describe the use of two reverse transcriptase quantitative polymerase chain reaction (RTqPCR) assays targeting JEV to screen archived samples from two wastewater treatment plants (WWTPs). JEV was detected in wastewater samples collected during a timeframe coinciding with a cluster of acute human encephalitis cases, alongside concurrent evidence of JEV detection in mosquito surveillance and the sentinel chicken programs within South Australia's Riverland and Murraylands regions. Current surveillance measures for JEV encounter multiple constraints, which may miss the early stages of JEV circulation or fail to capture the full extent of transmission. The detection of JEV in wastewater during a disease outbreak highlights the potential WBS has as a complementary layer to existing monitoring efforts forming part of the One Health approach required for optimal disease response and control.

PFI SI engine fueled with ethanol with exhaust gas rebreathing: Thermal efficiency optimization with thermodynamic modeling and ANN-PSO application

An ethanol-fueled Atkinson cycle PFI SI engine using exhaust rebreathing (ER) was evaluated under 110 different operating conditions. While ethanol is an important biofuel to reduce greenhouse gas emissions, Atkinson cycle engines have been studied as low-consumption alternatives for hybrid architecture vehicles. The operating conditions were validated with GT-Power® and the resulting combustion and performance parameters were trained by a series of artificial neural network (ANN) structures in order to learn and reproduce the non-linear correlations. The ANN structures were analyzed by number of nodes, hidden layers, and optimization methods. TPA results showed that ER tests had higher indicated thermal efficiency and lower combustion temperatures than both the standard Atkinson cycle and Otto cycle conventional throttled valve strategy with a similar engine setup. The best ANN to accurately predict all six outputs with easy-to-measure operating conditions was a combined ANN-PSO model, with two hidden layers with [30 10] nodes to predict net IMEP, airflow, total mass trapped and burned mass percentage, and a complementary 10-nodes PSO hidden layer, to predict PMEP, and the average exhaust runner temperature. The final model can predict and calibrate an Atkinson cycle PFI SI engine operating with ER with significant accuracy and no need for further TPA simulations.

MLGNet: Multi-Task Learning Network with Attention-Guided Mechanism for Segmenting Agricultural Fields

The implementation of precise agricultural fields can drive the intelligent development of agricultural production, and high-resolution remote sensing images provide convenience for obtaining precise fields. With the advancement of spatial resolution, the complexity and heterogeneity of land features are accentuated, making it challenging for existing methods to obtain structurally complete fields, especially in regions with blurred edges. Therefore, a multi-task learning network with attention-guided mechanism is introduced for segmenting agricultural fields. To be more specific, the attention-guided fusion module is used to learn complementary information layer by layer, while the multi-task learning scheme considers both edge detection and semantic segmentation task. Based on this, we further segmented the merged fields using broken edges, following the theory of connectivity perception. Finally, we chose three cities in The Netherlands as study areas for experimentation, and evaluated the extracted field regions and edges separately, the results showed that (1) The proposed method achieved the highest accuracy in three cities, with IoU of 91.27%, 93.05% and 89.76%, respectively. (2) The Qua metrics of the processed edges demonstrated improvements of 6%, 6%, and 5%, respectively. This work successfully segmented potential fields with blurred edges, indicating its potential for precision agriculture development.

Evaluation of low-voltage-driven multi-colored electrochromic device based on dry-deposited V2O5

A V2O5 film fabricated by a nanoparticle deposition system (NPDS) was used to demonstrate a highly durable electrochromic device (ECD). The V2O5 film deposited on both the electrodes functioned as a complementary layer during the redox reaction to balance the charge inside the device. Thereby, it mitigated the load applied to the ECD by enabling its electrochromic reaction within the range of ±1 V. The fabricated ECD showing different colors at opposite voltages were applied to both the electrodes. Meanwhile, a TiO2-based opaque electrolyte was used to show different colors of V2O5 thin films independently. The fabricated ECD can display three colors: yellow, green, and blue. Furthermore, each color variation is completed within 10 s. According to the International Commission on Illumination (CIE) data, the color differences (ΔE) between yellow and green, green and blue, and yellow and blue were measured to be approximately 27, 17, and 44, respectively. Meanwhile, the fabricated ECD showed almost a similar level of electrochromic performance even after 500 repeated runs. Moreover, the charge capacity of the ECD after a 10,000-cycle cyclic voltammetry (CV) analysis was 49.01 mC/cm2 (the initial charge capacity was measured to be 47.31 mC/cm2). This verified the high durability of the device. Thus, an ECD capable of coloration under a low voltage range of ±1 V was fabricated using a dry deposition method with a TiO2-based opaque electrolyte, to vividly display different colors at both sides of the device simultaneously. The unique device can independently display different colors on both the electrodes. The dry deposition method was applied to deposit an identical V2O5 electrochromic film on the electrodes and an opaque electrolyte. The device has potential applications in functional electrochromic displays.

Multifunctional and dynamically tunable coherent perfect absorber based on InSb and graphene metasurface

We propose a temperature-tunable and dual-broadband switchable coherent perfect absorber (CPA) composed of an annulus-disk-shaped InSb pattern and a complementary graphene layer. By controlling the Fermi level of graphene, the temperature of InSb, or the relative phase of incident beams, the working frequency and absorption of the CPA can be continuously adjusted. For a Fermi energy of 0 eV, the dual-band coherent perfect absorptivities exceed 99%. The designed structure achieves broadband absorptance of over 90% in the frequency range of 0.145 THz to 1.24 THz, with a relative bandwidth of about 158.12% for a Fermi energy of 0.5 eV. Moreover, the temperature-dependent permittivity of InSb enables thermal tuning of the dual-band CPA in the THz region. Furthermore, by altering the relative phase of input beams, the absorptivity can be continuously varied between less than 1.2% and more than 90% in the dual-band and broadband modes. Additionally, the designed CPA exhibits insensitivity to the polarization angle within the range of 0° to 90°. Therefore, this multifunctional CPA holds significant potential for applications in modulation, sensing, all-optical switches, and coherent photodetectors.

Flexible pressure and temperature dual-modality sensor based on stretchable electrode for human–machine interaction

Although flexible sensors have been widely used in areas such as human–computer interaction and electronic skin with their sensitive response and excellent robustness, their fabrication process remains complex and expensive. In addition, the flexible pressure sensor can only detect a single pressure. This paper presents a dual-mode pressure and temperature sensor with complementary layers based on stretchable electrodes. The templates required for sensor production are simple, easy to make and inexpensive. Comparing pressure sensors without complementary layers improves the sensitivity of devices with complementary layers more than 2.5 times. In addition, the pressure sensor enables dual-mode testing of pressure and temperature by modifying the complementary layer’s material while keeping the structure unchanged. The temperature sensor demonstrates pressure insensitivity and cyclic stability. The sensor shown some practical applications, such as finger pressing, gesture recognition, arm bending, and Morse code. Finally, sensors were integrated into the mechanical gripper to detect pressure and temperature during gripping. This work provides a promising way to improve the performance of flexible pressure sensors with easily prepared structures and to increase the integration of pressure and temperature dual-mode sensors, with great potential for applications in human–computer interaction and electronic skin.

Ontology-Based Expert System for Automated Monitoring of Building Energy Systems

Modern buildings have complex technical equipment that is hard to operate efficiently from a user’s point of view. Users and building managers therefore need guidance in terms of finding the most efficient operational strategies and monitoring plans to avoid faults and energy wastes. Current support systems can do that, but they must usually be adapted to each building manually. In this study, an expert system is proposed that provides a complementary analysis layer with semantic modeling and knowledge reuse. During the configuration phase, the system starts from a semantic description of a building energy system to identify potential efficiency risks and automatically apply generic monitoring functions and rules for building operation. In the operational phase, it generates advices based on continuous real-time analysis of building operational data. The current implementation of the expert system in 14 buildings proved that the approach can allow for a deployment on a larger scale.

Job Shop Scheduling with Limited-Capacity Buffers using Constraint Programming and Genetic Algorithms

This article aims to propose a new approach for solving production planning and scheduling in the process industries, in such a way to be adaptable to any manufacturing plant and exploring the use of innovative AI-style technologies. The main contributions of the work are: (i) the design of a specific data format to describe any manufacturing plant (including resources, layout and production recipes), being the input of the method; and (ii) the consideration of limited-capacity production lines with intermediate and final buffers in the optimization. The method involves two stages: the first one corresponds to a deterministic optimization algorithm based on Constraint Programming modelling to solve the JSSP in an ideal scenario with no storage limitation; while the second one is a Genetic Algorithm that only comes into play when the solutions obtained from the first one are infeasible for the available storage, so it is a complementary layer to try to solve the mismatches stochastically.

Titanium Carboxylate Molecular Layer Deposited Hybrid Films as Protective Coatings for Lithium-Ion Batteries.

The lifetime of lithium-ion batteries can be extended by applying protective coatings to the cathode's surface. Many studies explore atomic layer deposition (ALD) for this purpose. However, the complementary molecular layer deposition (MLD) technique might offer the benefit of depositing hybrid coatings that are flexible and can accommodate potential volume changes of the electrode during charging and discharging of the battery. This study reports the deposition of titanium carboxylate thin films via MLD. The structure and stability of the hybrid films are studied by using Fourier transform IR spectroscopy. The electrochemical properties of two titanium carboxylate films and a "titanicone" MLD film, deposited by using TDMAT and glycerol, are evaluated on top of a TiO2, TiN, and LiMn2O4 electrode. The coatings are found to present good lithium-ion kinetics and to reduce electrolyte decomposition. Overall, the titanium carboxylate films deposited in this work seem promising as protective and elastic coatings for future high-energy lithium-ion battery cathodes.

Optimization of Search Environments for Learning Contexts

This article proposes an improvement of search engines in a learning or training context. Indeed, the learner requests resources or learning content in a training or learning situation. The same goes for the trainer, who wishes to select the appropriate resources available to his learners. Unfortunately, existing search engines produce an enormous mass of content but sometimes do not match the learning context, thus causing an enormous loss of time for the learner or the teacher to find the appropriate resources among this important batch. Therefore, we suggest associating a complementary layer with search engines to extract the most relevant information related to learning or training situations from the engine results. For this purpose, an integrated filter eliminates irrelevant results to the current learning or training situation; and performs a weighted reclassification of these results based on Bloom’s taxonomy. In terms of the HMI, this layer allows having more informative result snippets. The experimentation of this environment is based on Google APIs. According to the Bloom hierarchy, the classification of the user question and the classification of the search results are carried out from Natural Language Processing based on Logistic Regression of Machine Learning Algorithms. The result obtained presents an intuitively favorable environment for education, leading to the implementation of a specific search engine capable of collecting, storing, and indexing educational concepts in the next stage of this project. A project to empirically evaluate the results obtained is currently underway.

Enhanced Electrochromic Performance of All-Solid-State Electrochromic Device Based on W-Doped NiO Films

Electrochromic materials have attracted much attention due to their promising applications in smart windows and thermal control. However, NiO is a weak point for a complementary ECD and needs to be improved due to its low optical modulation and charge density. In this work, the W-doped NiO films are designed and prepared by RF magnetron co-sputtering to improve the performance of the NiO. The results shows that the optical modulation of the W-NiO (52.7%) is significantly improved compared with pure NiO (33.8%), which can be assigned to the increase in lattice boundaries due to the W doping. The response time of W-NiO is 8.8 s for coloring and 7.2 s for bleaching, which is similar to that of NiO film. The all-solid-state electrochromic devices (ECDs) that employed W-NiO as a complementary layer are prepared and exhibit a high-transmittance modulation of 48.5% in wavelengths of 450–850 nm and an emittance modulation of 0.28 in 2.5–25 μm, showing great application potential in the field of smart windows and spacecraft thermal control devices. The strategy of preparing NiO doped by W indicates an innovative direction to obtain ECDs with high performance.

NiO films prepared by e-beam evaporation for Mg2+ based electrochromic devices

Electrochromic devices (ECDs) with reversible change of optical properties applying an external voltage, are the promising candidate for smart windows technology. In order to solve the unsafety of Li+ based electrolytes and the corrosiveness of acids, the Mg2+ has been used as the efficient insertion ion used in ECDs. However, all previous studies are present in cathode EC materials, in order to improve the optical modulation of complementary ECDs, it is relevant to study in anodic EC materials. In this work, the NiO films were deposited by e-beam evaporation and the annealing effect on the structure, morphology and optical properties were studied. For NiO films annealed at RT, the good cyclic stability and lager ΔT were obtained simultaneously. Meanwhile, the ECDs with the unique structure of ITO/WO3/MgCl2 aqueous solution/NiO/ITO were assembled. The devices showed the large optical transmittance modulations (50% at 630 nm) and the fast response (5.3 s for bleaching and 6.4 s for coloring). These findings not only demonstrate NiO films prepared by e-beam evaporation method are suitable to be applied as complementary EC layer, but also provide the broad prospect for the application of Mg2+ based ECDs.

Polarization-Insensitive Optically Transparent Microwave Metamaterial Absorber Using a Complementary Layer

A simple optically transparent absorber based on a double complementary structured layer of the indium-tin-oxide (ITO) deposited polyethylene terephthalate film is presented. The structure showed more than 90% absorption from 2 to 4.5 GHz of the frequency with a thickness of 0.0847 <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <inline-formula><tex-math notation="LaTeX">$\lambda _L$</tex-math></inline-formula></b> (wavelength corresponding to the lowest frequency of absorption band). The computed absorptivity of the proposed structure is validated using the transmission line theory and measured experimentally as well. The structure has polarization-insensitive response and is highly stable for the oblique wave incidence over a wide angular range. This absorber can be conformally wrapped on a curved surface and reduces the radar cross section (RCS) by more than 10 dB of a curve cylinder. This 10 dB RCS reduction covers almost the entire S-band of microwave frequencies. Optical transparency and flexibility of the proposed absorber make it suitable for a wide range of applications.

Elemental analysis by Metallobalance provides a complementary support layer over existing blood biochemistry panel-based cancer risk assessment.

Despite the benefit of early cancer screening, Japan has one of the lowest cancer screening rates among developed countries, possibly due to there being a lack of “a good test” that can provide sufficient levels of test sensitivity and accuracy without a large price tag. As a number of essential and trace elements have been intimately connected to the oncogenesis of cancer, Metallobalance, a recent development in elemental analysis utilizing the technique of inductively coupled plasma mass spectrometry has been developed and tested as a robust method for arrayed cancer risk screening. We have conducted case-control epidemiological studies in the prefecture of Chiba, in the Greater Tokyo Area, and sought to determine both Metallobalance screening’s effectiveness for predicting pan-cancer outcomes, and whether the method is capable enough to replace the more conventional antigen-based testing methods. Results suggest that MB screening provides some means of classification potential among cancer and non-cancer cases, and may work well as a complementary method to traditional antigen-based tumor marker testing, even in situations where tumor markers alone cannot discernibly identify cancer from non-cancer cases.

Ultra-wideband graphene-based absorber in the terahertz regime based on elliptical slots and a complementary sinusoidal-patterned dielectric layer.

A graphene-based absorber is presented based on elliptical slots and a complementary sinusoidal-patterned dielectric layer. The proposed absorber structure includes upper dielectric and metal film layers resulting in a Fabry-Perot cavity. The produced cavity enhances the confinement of electromagnetic waves. The presented absorber yields an absolute bandwidth of 4.02 THz (0.51-4.53 THz) considering an 0.88 absorbance level together with normal incidence. The presented structure benefits from an almost insensitive ultra-wideband absorbing performance as θ varies up to 50°and 60° for TE and TM polarizations, respectively. Moreover, the considered symmetry in the design procedure results in an almost insensitive structure with respect to the φ incident angle. Finally, the obtained 160% fractional bandwidth is much greater compared to mentioned previous works in literature.

N-Glycosylation can selectively block or foster different receptor\u2013ligand binding modes

While DNA encodes protein structure, glycans provide a complementary layer of information to protein function. As a prime example of the significance of glycans, the ability of the cell surface receptor CD44 to bind its ligand, hyaluronan, is modulated by N-glycosylation. However, the details of this modulation remain unclear. Based on atomistic simulations and NMR, we provide evidence that CD44 has multiple distinct binding sites for hyaluronan, and that N-glycosylation modulates their respective roles. We find that non-glycosylated CD44 favors the canonical sub-micromolar binding site, while glycosylated CD44 binds hyaluronan with an entirely different micromolar binding site. Our findings show (for the first time) how glycosylation can alter receptor affinity by shielding specific regions of the host protein, thereby promoting weaker binding modes. The mechanism revealed in this work emphasizes the importance of glycosylation in protein function and poses a challenge for protein structure determination where glycosylation is usually neglected.

Reduced graphene oxide and perylene derivative nanohybrid as multifunctional interlayer for organic solar cells

In this work, reduced graphene oxide:3,4,9,10-perylenetetracarboxylic dianhydride nanohybrid was prepared by a modified Hummers method which resulted in effective functionalization of graphene sheets. In this procedure, the perylene molecules were included at the reaction medium of graphene oxide, where the acid promotes hydrolysis of the anhydride, forming carboxylic acids; these groups react with hydroxyl groups of graphene oxide, generating ester bonds between graphene oxide and perylene, followed by a reduction through thermal annealing in air. The resulting interfacial nanohybrid film combines optical and electrical features of both materials, being a promising functional interlayer in organic-inorganic based devices. Herein, the thin film was tested in organic solar cells; the photovoltaic response pointed out that the dipole character of the nanohybrid enhances the fill factor and open circuit voltage parameters, when compared with the solar cell without buffer layer or having a polymeric hole transporting layer. After that, the optimized solar cells displayed open circuit voltage of 0.76 V, short circuit current density of 11.61 mA/cm2, fill factor of 53 % and power conversion efficiency of 4.70 % under AM1.5 illumination, where the nanohybrid film may act as a complementary absorbing layer and as hole injection layer, pointing out the potential use of this compound to improve the photovoltaic response in solar cells.