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In this work, the device modeling of n-i-p architecture based on FTO/WSe2/ CsSn x Ge 1 - x I 3 x = 0.5 /Spiro-OMeTAD/Au was performed using solar cell capacitance simulator-one dimensional (SCAPS-1D) tool. All simulations were performed in the 1.5G AM sunlight spectrum. The effect of various parameters such as defect density, thickness of absorber layer and work function of contact electrode have been investigated. The effect of temperature, series and shunt resistance have also been analyzed. After optimization of photovoltaic parameters, we obtained power conversion efficiency 18.51%, fill factor 79.41%, open circuit voltage (Voc) 0.8458 V and short-circuit current density (Jsc) 27.562 mA/cm2. The modeling of CsSn x Ge 1 - x I 3 x = 0.5 based devices open the door for the fabrication of feasible and highly efficient perovskite solar cells. [ABSTRACT FROM AUTHOR]

The molecular design and conformations of hole-transporting materials (HTM) have unravelled a strategy to enhance the performance of environmentally sustainable perovskite solar cells (PSC). Several attempts have been made and several are underway for improving the efficiency of PSCs by designing an efficient HTM, which is crucial to preventing corrosion, facilitating effective hole transportation, and preventing charge recombination. There is a need for a potential alternative to the current market-dominating HTM due to its high cost of production, dopant requirements, moisture sensitivity, and low stability. Among several proposed HTMs, molecules derived from thiophene exhibit unique behaviour, such as the interaction with under-coordinated Pb2+, thereby facilitating the passivation of surface defects in the perovskite layer. In addition, coupling a suitable side chain imparts a hydrophobic character, eventually leading to the development of a moisture-sensitive and highly stable PSC. Furthermore, thiophene-backboned polymers with ionic pendants have been employed as an interfacial layer between PSC layers, with the backbone facilitating efficient charge transfer. This perspective article comprehensively presents the design strategy, characterization, and function of HTMs associated with thiophene-derived molecules. Hence, it is observed that thiophene-formulated HTMs have an enhanced passivation effect, good performance in an open-circuit environment, longevity, humidity resistance, thermostability, good hole extraction, and mobility in a dopant-free condition. For a better understanding, the article provides a comparative description of the activity and function of thiophene-based small molecules and polymers and their effect on device performance. [ABSTRACT FROM AUTHOR]

This paper examines the problem of identifying network anomalies when processing data streams in industrial systems. A network anomaly refers to a malicious signature and the current context: network environment and topology, routing parameters, and node characteristics. As a result of the study, it is proposed to use a neocortex model that supports the memory mechanism to detect network anomalies. [ABSTRACT FROM AUTHOR]

This study considers the problem of detecting network anomalies caused by computer attacks in the networks of the industrial Internet of things. To detect anomalies, a new method is proposed, built using a hierarchical temporal memory (HTM) computation model based on the neocortex model. An experimental study of the developed method of detecting computer attacks based on the HTM model showed the superiority of the developed solution over the LSTM analog. The developed prototype of the anomaly detection system provides continuous training on unlabeled data sets in real time, takes into account the current network context, and applies the accumulated experience by supporting the memory mechanism. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have garnered the attention of researchers in recent years as they have been able to attain high efficiency within a short time. In the present study, the hybrid organic inorganic lead iodide perovskite has been used as the sensitizer. Successful fabrication of a hybrid lead halide perovskite sensitized solar cell (PSC) with copper iodide as a medium for transporting holes (HTM) has been performed in a sandwich structure. The synthesized CH3NH3PbI3 material and HTM have undergone various characterization processes, such as XRD, UV–Vis, SEM, and EDX. The present work is based on the synthesis of perovskite, HTM, and polymer electrolyte and their application in a PSC at room ambient following the sandwich structure. A planar WE/TiO2/CH3NH3PbI3/HTM/electrolyte/CE structure was fabricated through solution-processed spin-coating. The electrical properties of the PSC were measured through a solar simulator, and it attained an efficiency of 13.64%, with V oc = 0.63 V and Jsc = 33 mA cm 2 with fill factor = 0.65. This work shows the sandwich-structured fabrication of the PSC in ambient condition with a considerably good efficiency which represents the novelty of the work. [ABSTRACT FROM AUTHOR]

Purpose: This study measures the impact of implementation of the Improved Decentralized Maintenance Model on the functionality and availability of medical equipment in Burundi's resource constrained health care system with hypothesis that the model has a measurable impact. Methods: The initial model was tested in 2 provinces before being improved and extended to the provinces of Bujumbura and Rumonge. It is composed by 4 interrelated main axes (Maintenance management, Human, Financial and Material resources,). This study analyses the effects of this implementation between October 2020 and February 2022. Results: The rate of medical equipment functional in service has increased substantially, respectively +8% in the province of Bujumbura and 2% in the province of Rumonge, and the rate of medical equipment requiring maintenance has fallen by 9.7% (Bujumbura) and 2% (Rumonge). The provinces implementing the model have convincing results in terms of functionality with scores of at least 80%, while the national average is 64%. Conclusions: There is a notable positive change between 2020 and 2022 in the functionality of medical equipment and a decrease in equipment awaiting maintenance, and therefore in its availability. This study proves that a sustainable implementation of a decentralized maintenance model is feasible and highly useful in low-resource settings due to its affordability. The context of a low-resource country is a challenge in itself, but the model developed shows that by tackling the low-resource levels of preventive maintenance, we can have some impact on the functionality of the equipment and therefore on the quality of care. [ABSTRACT FROM AUTHOR]

The Spiro-OMeTAD is an excellent candidate for application as hole transport material (HTM), but its high hygroscopicity, inclination to crystallize, and fragility to moisture and heat make it unsuitable for solar cells. Thus, it is of interest to investigate other HTM candidates. In this paper, the use of p-type InGaAs as hole transport material (HTM) has been suggested to enhance the performance of perovskite-based solar cells (PSC). The simulation of a hybrid CH3NH3PbI3/InGaAs planar heterojunction perovskite solar cell is performed using the Silvaco ATLAS simulator. In order to confirm the predictability of the proposed simulation methodology, the conventional ITO/TiO2/MAPbI3/Spiro-OMeTAD structure is simulated, and shows good coherence with experimental results. The proposed design using InGaAs as HTM outperforms the conventional device in terms of short-circuit current density (JSC) of 37.2 mA/cm2, open-circuit voltage (VOC) of 1 V, fill factor (FF) of 80% and high value of efficiency. In addition, the findings show that with In content of x = 0.7 the efficiency will improve to reach a value of about 30%. [ABSTRACT FROM AUTHOR]

High efficiency perovskite solar cells are usually achieved with expensive hole transport materials (HTM), such as PTAA and Spiro-OMeTAD. To bring this technology to industry it is essential to find alternative HTM. In this work, we show results with the inexpensive inorganic semiconductor CuSCN as HTM in inverted device structure. We first studied the interaction between CuSCN and the perovskite solution by performing solubility test and found out that CuSCN can be dissolved in perovskite solution. Then devices were fabricated using single-step deposition technique and sequential deposition technique were first a PbI2 layer is first deposited that could overcome the potential incompatibility of the perovskite solution with the CuSCN. Solar cells with Voc > 1000 mV were successfully fabricated with the 2-step process but demonstrated lower efficiencies compared to the 1-step process due to a lower Jsc. [ABSTRACT FROM AUTHOR]

An ultimate goal of placing fire detection systems in buildings and structures is to allow for the rapid detection of fire and accurate faster than real time prediction of ensuing fire behavior so that relevant information can be delivered to the appropriate stakeholders. In the near-term, development of detection systems with decreased detection time, better discrimination against nuisance and false alarms, and real-time monitoring of the fire state is a critical interim step. Building comfort and efficiency systems are increasingly incorporating a greater quantity of sensors and these sensors are installed at a greater density than any fire sensor with the exception of the sprinkler. While currently used primarily for building management purposes, the application of these, or similar types of building sensors, for rapid fire detection, fire state determination, and fire forecasting offers great potential. This paper discusses the potential benefits of the application of Hierarchical Temporal Memory algorithms for fire state determination in a continuous learning environment based on its application to a series of live fire experiments. [ABSTRACT FROM AUTHOR]

In this work, easy and simple structured perovskite solar cells (PSCs) are designed and characterized. Our effort was to reduce the cost of the fabrication of such PSC devices, first by using an inexpensive starting precursor (aqueous methylamine solution) for the perovskite materials and second by design in a PSC structure free of the expensive hole transport layer (HTL). The CH3NH3PbI3 perovskite sols were deposited onto a conductive FTO glass using the spin coating technique followed by heating at 100 °C for 10 min. The structure of the films was characterized by X-ray diffraction (XRD) and their optical properties by UV–VIS spectrophotometry and photoluminescence (PL). The obtained phase confirmed the formation of a tetragonal perovskite structure. Two different solvents have been used, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). The effect of the type and the concentration of the used solvent DMF and DMSO on the performance of the solar cells have been investigated. It was found that a 40% concentration of the perovskite material resulted in the optimum film thickness that gives the best photoelectric performance. The DMF-based PSC assembled solar cell exhibited the best performance with an open circuit voltage of 750 mV, a photocurrent density of 12.5 mA/cm2, and an overall photon to electric conversion efficiency of 5.7%; all these results are higher than those of cells made with DMSO. Highlights: Easy and simple structured perovskite solar cells free of the hole transport layer were designed for efficient low-cost organolead halide perovskites solar cells by using inexpensive precursors. The influence of the concentration and the type of the solvent of the obtained perovskite materials on the performance of the solar cell have been investigated. For both the used solvents (DMF and DMSO), it was found that a 40% concentration is the optimum to obtain better performance for the DMF-based PSC. An open circuit voltage of 750 mV, a photocurrent density of 12.5 mA/cm2 with an overall photon to electric conversion efficiency of 5.7% was obtained. [ABSTRACT FROM AUTHOR]

An attempt has been made to fabricate methyl ammonium tin chloride (CHNHSnCl) perovskite-sensitized TiO nanostructure photoanode solar cell with hole transport material (HTM) spiro-MeOTAD and graphite-coated counter electrode (CE). The TiO nanoparticles (TNPs), TiO nanoleaves (TNLs), and TNLs with MgO core/shell photoanodes were prepared to fabricate perovskite-sensitized solar cells (PSSCs). The prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The photovoltaic characteristics of the PSSCs, photocurrent density ( J ), open-circuit voltage ( V ), fill factor (FF), and power conversion efficiency (PCE) were determined under illumination of AM 1.5 G. Electrochemical impedance spectroscopy (EIS) analysis was carried out to study the charge transport and lifetime of charge carriers at the photoanode-sensitizer-electrolyte interface of the PSSCs. The PSSC made with CHNHSnCl perovskite-sensitized TNL-MgO core/shell photoanode and spiro-MeOTAD HTM shows an impressive photovoltaic performance, with J = 17.24 mA/cm, V = 800 mV, FF = 73 %, and PCE = 9.98 % under 100 mW/cm light intensity. The advent of such simple solution-processed mesoscopic heterojunction solar cells paves the way to realize low-cost and high-efficiency solar cells. By the aid of electrochemical impedance spectroscopy, it is revealed that the core/shell structure can increase an interfacial resistance of the photoanode-CHNHSnCl interface and retard an electron recombination process in the photoanode-sensitizer-HTM interface. [ABSTRACT FROM AUTHOR]

This work investigates the proficiency of acceptor-donor-acceptor (A-D-A) organic dye Diisopropyl azodicarboxylate (DIAC) as photosensitizer on the photovoltaic parameters of silver (Ag) doped TiO photoanode dye-sensitized solar cells (DSSCs) with quasi-solid state electrolyte/hole transport material (HTM) spiro-MeOTAD. TNSs (TiO nanosticks) photoanodes are prepared through sol-gel method and hydrothermal technique. X-ray powder diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and BET measurement were used to characterize the structure and morphology of TiO nanostructures. The Diisopropyl azodicarboxylate organic dye with TNPs-Ag@TNSs composite photoanode structure and spiro-MeOTAD HTM exhibited better power conversion efficiency (PCE). [ABSTRACT FROM AUTHOR]