Reliable Retention Research Articles

A flexible nickel phthalocyanine resistive random access memory with multi-level data storage capability

Metal phthalocyanine is considered one of the most promising candidates for the design and fabrication of flexible resistive random access memory (RRAM) devices due to its intrinsic flexibility and excellent functionality. However, performance degradation and the lack of multi-level capability, which can directly expand the storage capacity in one memory cell without sacrificing additional layout area, are the primary obstacles to the use of metal phthalocyanine RRAMs in information storage. Here, a flexible RRAM with pristine nickel phthalocyanine (NiPc) as the resistive layer is reported for multi-level data storage. Due to its high trap-concentration, the charge transport behavior of the device agrees well with classical space charge limited conduction controlled by traps, leading to an excellent performance, including a high on-off current ratio of 107, a long-term retention of 106 s, a reproducible endurance over 6000 cycles, long-term flexibility at a bending strain of 0.6 %, a write speed of 50 ns under sequential bias pulses and the capability of multi-level data storage with reliable retention and uniformity.

Bulk Glassy GeTe2: A Missing Member of the Tetrahedral GeX2 Family and a Precursor for the Next Generation of Phase-Change Materials

Vitreous germanium disulfide GeS2 and diselenide GeSe2 belong to canonical chalcogenide glasses extensively studied over the past half century. Their high-temperature orthorhombic polymorphs are congruently melting compounds, and the tetrahedral crystal and glass structure is largely preserved in the melt. In contrast, the ditelluride counterpart is absent in the Ge–Te phase diagram, which shows only a single compound, monotelluride GeTe. Phase-change materials based on GeTe have become a technologically important class of solids, and their structure and properties are also widely studied. Surprisingly, very scarce information is available for alloys having GeTe2 stoichiometry. Using a fast quenching procedure in silica capillaries, high-energy X-ray diffraction, and Raman spectroscopy supported by first-principles simulations, we show that bulk glassy GeTe2 differs substantially from the lighter GeX2 members, revealing 46% of trigonal germanium, 31% of three-fold coordinated tellurium, and only 20% of edge-sharing tetrahedra or pyramids. The fraction of homopolar Ge–Ge bonds is low; however, the population of dominant Te–Te dimers and Ten oligomers, n ≤ 10, appears to be significant. The complex structural and chemical topology of g-GeTe2 is directly related to the thermodynamic metastability of germanium ditelluride, schematically represented by the following reaction: GeTe2 ⇄ GeTe + Te. Disproportionation is complete above liquidus in the temperature range of semiconductor–metal transition, and the dense metallic GeTe2 liquid, mostly consisting of five-fold coordinated Ge species, exhibits high fluidity, strong fragility (m = 99 ± 5), and presumably a fast structural transformation rate combined with low atomic mobility in the vicinity of the glass transition temperature, favorable for reliable long-term data retention in nonvolatile memories. The observed and predicted characteristic features make GeTe2 a promising precursor for the next generation of phase-change materials, especially coupled with additional metal doping, depolymerizing the tetrahedral interconnected glass network and accelerating (sub)nanosecond crystallization.

Bipolar, complementary resistive switching and synaptic properties of sputtering deposited ZnSnO-based devices for electronic synapses

In this work, ZnSnO-based resistive switching (RS) devices were fabricated with different top electrodes (TEs) to investigate the RS and synaptic characteristics for neuromorphic systems. The Ta/ZnSnO/TiN device exhibits excellent endurance (2000 DC cycles), longer retention (104 s), reliable multilevel retention (103 s) with six distinct resistance states via controlling the reset-stop voltage, and low forming/set voltages with high uniformity. Besides, complementary RS (CRS) behavior is observed in Ta/ZnSnO/TiN device at appropriate current compliance (CC, 5 mA) instead of low (600 μA) and high (10 mA) CC, respectively. X-ray photoelectron spectroscopy (XPS) analysis confirms that both TaO and TiON interface layers are formed at the top Ta/ZnSnO and bottom ZnSnO/TiN interfaces, which are found responsible for CRS behavior. Furthermore, XPS analysis also confirmed that the concentration of oxygen vacancies near the bottom ZnSnO/TiON interface is greater than the oxygen vacancies concentration near the top TaO/ZnSnO interface. Based on the XPS analysis, the switching phenomenon is confined in ZnSnO/TaON bottom interface because of its higher oxygen vacancy levels (prevent oxygen loss) in contrast to the TaO/ZnSnO top interface where the ZnSnO layer acts as series resistances in between these two interfaces. The basic features of an artificial synapse, LTP/ LTD, PPF/ PPD, and STDP, were successfully emulated using a Ta/ZnSnO/TiN device, suggesting potential applications for neuromorphic hardware systems.

Rehabilitation of facial defect on a unique case of disfigurement

Rehabilitation of facial disfigurement after a surgery or trauma is difficult to address as it involves individuality of the patient. Face being the visual pro forma, rehabilitating it is always a challenging task. This is predominantly due to the presence of soft tissue, lack of anatomic undercut, and increased muscle activity. The use of osseointegrated implants provides the most reliable retention, however, placing it on an intact facial defect further complicates rehabilitation. This case report is about rehabilitation of lost facial feature after tumor resection surgery.

Longevity of Commodity DRAMs in Harsh Environments Through Thermoelectric Cooling

Today, more and more commodity hardware devices are used in safety-critical applications, such as advanced driver assistance systems in automotive. These applications demand very high reliability of electronic components even in adverse environmental conditions, such as high temperatures. Ensuring the reliability of microelectronic components is a major challenge at these high temperatures. The computing systems of these applications rely on DRAMs as working memory, which are built upon bit cells that store charges in capacitors. These commodity DRAMs are optimized for cost per bit and not for high reliability. Thus, very high temperatures impose an enormous challenge for commodity DRAMs as the data retention time and reliability decrease largely, affecting the data correctness. Data correctness can be ensured up to certain temperatures by increasing the refresh rate to counterbalance the retention time reduction. However, this severely degrades the access latencies and the usable DRAM bandwidth. To overcome these limitations, we present for the first time a Thermoelectric Cooling (TEC) solution for commodity DRAMs in harsh-environments, such as automotive. Our TEC solution enables the use of commodity off-the-shelf DRAMs in safety-critical applications by reducing the temperature conditions to a range where they can operate reliably. This TEC solution is applied a posteriori to the DRAM chips without using high-cost package solutions. Thus, it maintains the low-cost targets of such devices, improves the reliability, and at the same time, counterbalances the adverse effects of increasing the refresh rate. To quantitatively evaluate the benefits of TEC on commodity DRAMs in harsh-environments, we performed system-level evaluations with several applications backed up by the measured data on commodity DRAMs. Our experimental results, using accurate multi-physics simulations that employ finite element method, demonstrate that the TEC-based cooling ensures that the maximum temperature of all DRAM chips is always below 85°C despite that the original on-chip temperature (i.e., in the absence of our TEC based cooling) goes beyond 120°C.

MINIMUM NUMBER OF POINTS FOR A RELIABLE SOIL WATER RETENTION CURVE USING RICHARDS’ PRESSURE CHAMBER

The soil hydro-physical characteristics are very important for studies about soil water dynamics. The soil water retention curve it is a soil characteristic sometimes expensive and time consuming to be done and could be a problem for farmers. The numbers of points and its tension evaluated are normally choose arbitrarily. This study aimed to define the fewest pairs of soil moisture and water soil potential points which result in a reliable water retention curve in two different soils (sandy and clay). Using different tensions by suction table and Richards’ pressure chamber, nine replications were adjusted by van Genuchten's equation. Curves with 4, 5, 7, 8, 9, 10 and 13 points were studied and the curve with 13 points was adopted as standard. The obtained parameters for different pairs of soil moisture and their corresponding soil water potential were compared to the equivalent standard curve and submitted to analysis of variance (F test), and their values were compared by the Scott-Knott test (5% of probability). The curve with 7 points, using the tensions of 0; 40; 100; 300; 1,000; 5,000 e 15,000 hPa, was the lower number of points that did not showed statistical difference in any parameters of the model and the point with 15,000 hPa shown to be important and should be used on the combination of points to obtain a good adjustment.

Trade‐Off Between Data Retention and Switching Speed in Resistive Switching ReRAM Devices

AbstractMemristive switching devices are promising for future data storage and neuromorphic computing applications to overcome the scaling and power dissipation limits of classical CMOS technology. Many groups have engineered bilayer oxide structures to enhance the switching performance especially in terms of retention and device reliability. Here, introducing retention enhancement oxide layers into the memristive stack is shown to result in a reduction of the switching speed not only by changing the voltage and temperature distribution in the cell, but also by influencing the rate‐limiting‐step of the switching kinetics. In particular, it is demonstrated that by introducing a retention enhancement layer into resistive switching SrTiO3 devices, the kinetics are no longer determined by the interface exchange reaction between switching oxide and active electrode, but depend on the oxygen ion migration in the additional interface layer. Thus, the oxygen migration barrier in the additional layer determines the switching speed. This trade‐off between retention and switching speed is of general importance for rational engineering of memristive devices.

Recipe for ultrafast and persistent phase-change memory materials

The contradictory nature of increasing the crystallization speed while extending the amorphous stability for phase-change materials (PCMs) has long been the bottleneck in pursuing ultrafast yet persistent phase-change random-access memory. Scandium antimony telluride alloy (ScxSb2Te3) represents a feasible route to resolve this issue, as it allows a subnanosecond SET speed but years of reliable retention of the RESET state. To achieve the best device performances, the optimal composition and its underlying working mechanism need to be unraveled. Here, by tuning the doping dose of Sc, we demonstrate that Sc0.3Sb2Te3 has the fastest crystallization speed and fairly improved data nonvolatility. The simultaneous improvement in such ‘conflicting’ features stems from reconciling two dynamics factors. First, promoting heterogeneous nucleation at elevated temperatures requires a higher Sc dose to stabilize more precursors, which also helps suppress atomic diffusion near ambient temperatures to ensure a rather stable amorphous phase. Second, however, enlarging the kinetic contrast through a fragile-to-strong crossover in the supercooled liquid regime should require a moderate Sc content; otherwise, the atomic mobility for crystal growth at elevated temperatures will be considerably suppressed. Our work thus reveals the recipe by tailoring the crystallization kinetics to design superior PCMs for the development of high-performance phase-change working memory technology.

A two-step microengineered system for high-density cell retention from bioreactors

Large-scale cell culture processes are required to produce biopharmaceuticals, cells for tissue engineering, and vaccine production while being effective in toxicity testing, gene therapy vector production for cancer research, and drug development. A growing trend in these industries, particularly for suspension cells, involves implementation of continuous cell perfusion processes, which require an aseptic, efficient, cost-effective, and reliable cell separation and retention scheme. Many cell separation techniques (membrane-based systems, lateral displacement devices, and acoustophoresis) have proven to be highly efficient, but suffer from issue of clogging and high cost, limiting their reliability, and thus, their overall feasibility. Some cell retention devices—those based on inertial microfluidics—offer high reliability (i.e., clog-free), but their efficiency reduces at higher cell concentrations. To overcome this apparent trade-off, we report the development of an integrated system consisting of two different membrane-less microfiltration techniques for cell separation from spent cell media. Although it could be adapted to numerous cell culture applications, this system was optimized and tested for suspension-adapted Chinese Hamster Ovary (CHO) cells. As the first step of the cell retention system, a miniaturised hydrocyclone was developed that could separate the cells with macroscopic volume processing rates (~200 mL/min). At this stage, up to 75% of the cells were isolated with minimal (<5%) change in the viability. The remaining cells passed through the overflow of the device and entered to a multiplexed spiral microchannel system, where more than 90% of the remaining cells were recovered, yielding an overall efficiency of up to 95%. The proposed integrated system is thus ideal for continuous and high throughput cell retention even at high cell concentrations (~80 million cells/mL), which is in range of current need in the bioprocessing industry.

Resistive Switching Characteristics of Nonvolatile Memory with HSQ Film Using Microwave Irradiation.

In this study, we fabricated a resistive random access memory (ReRAM) of metal-insulator-metal structures using a hydrogen silsesquioxane (HSQ) film that was deposited by a low-cost solution process as a resistance switching (RS) layer. For post-deposition annealing (PDA) to improve the switching performance of HSQ-based ReRAMs, we applied high energy-efficient microwave irradiation (MWI). For comparison, ReRAMs with an as-deposited HSQ layer or a conventional thermally annealed (CTA) HSQ layer were also prepared. The RS characteristics, molecular structure modification of the HSQ layer, and reliability of the MWI-treated ReRAM were evaluated and compared with the as-deposited or CTA-treated devices. Typical bipolar RS (BRS) behavior was observed in all the fabricated HSQ-based ReRAM devices. In the low-voltage region of the high-resistance state (HRS) as well as the low-resistance state, current flows through the HSQ layer by an ohmic conduction mechanism. However, as the applied voltage increases in HRS, the current slope increases nonlinearly and follows the Poole-Frenkel conduction mechanism. The RS characteristics of the HSQ layer depend on the molecular structure, and when the PDA changes from a cage-like structure to a cross-linked network, memory characteristics are improved. In particular, the MWI-treated HSQ ReRAM has the largest memory window at the smallest operating power and demonstrated a stable endurance during the DC cycling test over 500 times and reliable retention at room (25 °C) and high (85 °C) temperatures for 10⁴ seconds.

Filamentary and interface switching of CMOS-compatible Ta2O5 memristor for non-volatile memory and synaptic devices

To successively implement synaptic memristor device in the neuromorphic computing system, it is essential to perform a variety of synaptic characteristics with low power consumption and have complementary metal-oxidesemiconductor (CMOS) compatibility. In this work, we experimentally demonstrate two types of interface and filamentary resistive switching behaviors for Ni/Ta2O5/Si device by controlling electroforming process. The typical bipolar operation with filamentary switching is observed with electroforming for non-volatile memory properties such as reliable retention (>104) and high on/off ratio (>103). To achieve the synaptic characteristics such as paired pulse facilitation (PPF), potentiation, and depression, the gradual switching with low current without electroforming is used. We evaluate pattern recognition accuracy simulation from Fashion MNIST dataset by using a 3-layer neural network (784 × 512 × 10) and synaptic weight of Ni/Ta2O5/Si device. Furthermore, density of states, isosurface charge density and electron localization function plots confirm the conductivity and charge formation of Ta2O5 structure with and without oxygen vacancies. Theoretical work results reveal that the resistive switching characteristics are due to charge accumulation/depletion near the defects sites (oxygen vacancy). All things considered, the Ni/Ta2O5/p++-Si memristor could offer the flexibility for both non-volatile memory and synaptic devices by simply controlling electroforming.

A Study of the Relationship Between Endurance and Retention Reliability for a HfOₓ-Based Resistive Switching Memory

This study determines the relationship between retention and endurance reliability for a HfOx-based resistive random access memory (ReRAM). A TiN (15 nm) / HfOx (6 nm) / Ti (10 nm) / TiN (40 nm) stacked structure is fabricated and tested to verify its basic characteristics and reliability. The high resistance states (HRS) retention behavior is characterized and is found to degrade over 100x on the endured bits because there is a sequential high temperature procedure. The degradation is reduced slightly to a ~30x drop for the endured devices with one single refresh cycle. During the endurance and retention test procedures, the HRS resistance decreases because neutral oxygen vacancy filaments grow and this cannot be reversed. The I-V characteristics for endured devices are also determined. The results show that isothermal treatment causes a gradual SET and RESET process with multiple feasible states. The thermally induced filament degradation model (isolated filament vs. continuous filament) is verified by the relationship between retention and endurance reliability. Design guidance is recommended for an improvement in ReRAM reliability.

PECULIARITIES OF USING ORTHODONTIC ACTIVATORS FOR DISTAL BITE AND APPLICATION OF RETENTION APPARATUS TO RETAIN RESULTS

Relevance. Distal occlusion is accompanied by certain morphological, functional, and aesthetic changes, in which there are disorders of external respiration, speech disorders, dysfunction of chewing, and swallowing. Today the problem of treatment of occlusion anomalies is not completely solved. The presence of errors and complications in the treatment of distal occlusion, the presence of recurrence of the disease in the form of a double occlusion, which necessitates repeated, and often unsuccessful treatment, indicates that the problem is still far from its final solution.&#x0D; Objective: to investigate the effectiveness of the use of orthodontic activators for the treatment of distal occlusion and retention devices to maintain the results of treatment.&#x0D; Materials and methods. 126 children aged 9-12 years with distal occlusion are divided into 2 groups. Group I (n=63) – children with distal occlusion and physiological type of respiration; Group II (n=63) – children with distal occlusion and pathological (oral) type of breathing. Conducted clinical, myographic, and anthropometric studies. All patients were treated by wearing a removable functional two-jaw orthodontic activator for at least 16 hours a day, with mandatory use during sleep, for 6 months. In addition to this hardware method of treatment, preventive measures were prescribed: myogymnastic and breathing exercises. The correction of the orthodontic activator was performed once a month. A control electromyographic study to determine the effectiveness of treatment was performed 3 months after the start of treatment (selectively, in some patients - also in the sixth month of treatment). Nylon floss, to keep the teeth in the achieved position.&#x0D; Results. The study of the designs of retention devices and comparison of their effectiveness showed that after active orthodontic treatment the most effective retention can be achieved by using a retainer made of flex wire and nylon thread impregnated with liquid photopolymer. The most optimal way to fix the fixed retention apparatus was as follows: complete completion of the active period of treatment; control of fissure-tubercle contact; professional teeth cleaning; conducting X-ray control to identify the position of the roots of the teeth; production of gypsum models and their fixation in the occluder; detection of contact points of the frontal group of teeth; detection of the location of the retainer in the oral cavity; making a retainer indirectly; fixation of the retention apparatus in the oral cavity. Our proposed method of manufacturing and fixing non-removable retainers with the use of nylon thread allows us to achieve reliable long-term retention of the achieved positive results after active orthodontic treatment.&#x0D; Analysis of the study data of children aged 9-12 years with distal occlusion and pathological (oral) type of respiration compared with the control group showed an increase in all measured EMG parameters for the temporalis muscles (in the range of 16-31.1±3.12%) and reduction - for the actual masticatory and circular muscles of the mouth (in the range of 17.0-29.8±3.09% and 16.8-35.9%, respectively). The total deviation of the values of the obtained indicators from the normative ranges from 16.0 to 35.9 ±2.56%. These abnormalities can be seen as a manifestation of the formation of a pathological muscle reaction, accompanied by negative changes in the appearance of the patient.&#x0D; The design of a removable functionally acting two maxillary orthodontic activators for simultaneous treatment of distal occlusion and dysfunction of masticatory and facial muscles in children with physiological and pathological types of respiration has been developed. It consists of a monoblock and a vestibular plate, monolithically connected to each other.&#x0D; Conclusions. In patients with distal occlusion, treatment with a removable functional two-jaw orthodontic activator helps to restore myodynamic balance in the dental system, resulting in improved patient facial expression, self-esteem, and quality of life. Wearing non-removable retainers with the use of nylon thread allows us to achieve reliable long-term retention of the achieved positive results after active orthodontic treatment.

Improvement of quantitative structure–retention relationship models for chromatographic retention prediction of peptides applying individual local partial least squares models

In Reversed-Phase Liquid Chromatography, Quantitative Structure–Retention Relationship (QSRR) models for retention prediction of peptides can be built, starting from large sets of theoretical molecular descriptors. Good predictive QSRR models can be obtained after selecting the most informative descriptors. Reliable retention prediction may be an aid in the correct identification of proteins/peptides in proteomics and in chromatographic method development. Traditionally, global QSRR models are built, using a calibration set containing a representative range of analytes. In this study, a strategy is presented to build individual local Partial Least Squares (PLS) models for peptides, based on selected local calibration samples, most similar to the specific query peptide to be predicted. Similar local calibration peptides are selected from a possible calibration set. The calibration samples with the lowest Euclidian distances to the query peptide are considered as most similar. Two Euclidian distances are investigated as similarity parameter, (i) in the autoscaled descriptor space and, (ii) in the PLS factor space of the global calibration samples, both after variable selection by the Final Complexity Adapted Models (FCAM) method. The predictive abilities of individual local QSRR PLS models for peptides, developed with both Euclidian distances, are found significantly better than those of two global models, i.e. before and after FCAM variable selection. The predictive abilities of the local models, developed with distances calculated in the PLS factor space, were best.

A Study on the Temperature-Dependent Operation of Fluorite-Structure-Based Ferroelectric HfO2 Memory FeFET: Pyroelectricity and Reliability

We report on the high-temperature operation and reliability of the Si-doped hafnium oxide (HSO) ferroelectric FET (FeFET) emerging memory. In this study, we explore the role of high-temperature operation of the ferroelectric (FE) material on the FeFET in the temperature range of 40-120 °C. The inverse memory window (MW) dependence on temperature leads to a very small MW size (~300 mV) at 120 °C. The recovery of MW size at room temperature (RT) indicates a potential pyroelectric effect as a cause for MW closure upon high-temperature operation. The FeFET state readout shows pronounced effects to erase (ER) threshold voltage (Vth) shift, due to the decrease in remnant polarization and improved substrate Vth shift as the temperature increases. The endurance reliability measured for temperature range (-40 °C to 40 °C) with 105 cycles shows a maximized initial MW at low temperatures, whereas higher postcycling interface trap generation occurs as the temperature increases. The FeFET 10 h retention tests at 0 °C and 40 °C were extrapolated to ten years and indicated stable properties independent of temperature. The depolarization field (Ed) dependence on the FeFET stack parameters is studied based on an analytical formula. The Ed decreases with increased permittivity of the FE, interface layer (IL), and increased FE film thickness. Substrate doping and temperature seem to have a small impact on E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> , whereas the FE-IL area ratio tuning below unity lowers the E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> . The role of pyroelectric effect on the FeFET memory and operating temperature-induced endurance and retention reliability concerns are discussed.

Ti-doped alumina based reliable resistive switching in sub- μ A regime

We investigated the low current resistive switching behavior using Ti-doped Al2O3 and sub-stoichiometric TaOx layers. The optimized concentrations of Ti and O in each Al2O3 and TaOx layer can make the resistive switching device show the stable retention characteristic and 3-bit operation in the current regime under 1 μA. Doped Ti in the Al2O3 layer generated oxygen vacancies to facilitate fluent resistive switching, and the TaOx layer with an appropriate oxygen concentration played the role of an oxygen reservoir and load resistance for reliable retention and electric pulse compatible characteristics, respectively. We presented the materials optimization processes and comparative resistive switching characteristics in detail.

Should I stay or should I go? Visit frequency as fitness centre retention strategy

ABSTRACT Rationale/Purpose: While there have been many previous studies on the impact of service quality, satisfaction, and loyalty on retention, mainly through qualitative surveys, there has not been an in-depth observation of the direct impact of visit frequency on long-term commitment using quantitative data. Design/methodology/approach: This study empirically tests 2,385 members across a chain of fifty fitness clubs in South Korea for one year from membership enrolment using logistics regression analysis. Findings: The research reveals and validates that visit frequency plays a significant impact. It shows that the member’s age also has a significant impact on the frequency and retention. This study shows how the first quarter of the year demonstrates a pattern to enhance retention predictability and reliability. Practical implications: With these findings, this study offers implications for retention-related factors in the earlier period of membership rather than tangible fitness centre-related factors in enhancing retention and long-term commitment to physical exercise. Research contribution: This is the first study that reveals the drop-out predictability by directly establishing the relationship of visit frequency and membership retention by tracking a one-year membership cycle.

Robust and Transient Write‐Once‐Read‐Many‐Times Memory Device Based on Hybrid Perovskite Film with Novel Room Temperature Molten Salt Solvent

AbstractOrganic–inorganic hybrid perovskites (OIHPs) have emerged as a novel class of functional materials with applications in solar cells, photodetectors, light‐emitting diodes, and resistive switching memories. Generally, perovskite films are fabricated with toxic solvents and antisolvent technique under inert atmosphere, which limits the commercial applications of OIHP‐based devices. To address this issue, uniform CH3NH3PbBr3 (MAPbBr3) film is fabricated through a facile one‐step spin‐coating method by directly dissolving perovskite precursor in a room‐temperature molten salt methylammonium acetate under air ambient condition. The nonvolatile resistive switching devices based on MAPbBr3 exhibit robust and reproducible write‐once‐read‐many‐times (WORM) memory properties with a large ON/OFF ratio (106), reliable retention properties (104 s), and somewhat ternary resistive characteristic. The conductive filaments in the perovskite thin film are proposed to induce the electrical conductivity switching. Additionally, the MAPbBr3 films can be dissolved rapidly in deionized water within 5 s, showing the transient characteristics. This work demonstrates a new perspective on the perovskite film fabrication and shows the potential application of MAPbBr3 in transient WORM devices.

Experimental Studies on the Reactive Thrust of the Mobile Robot of Arbitrary Orientation

The problem of creating mobile robots of arbitrary orientation in the technological space is to ensure reliable retention of robots on the surface of any orientation. Therefore, well-known experimental studies are mainly devoted to the creation of systems for coupling the robot to the surface along which it moves. The purpose of this study is to create a device for compensating the gravitational load of a mobile robot. The article contains the results of experimental testing of a fundamentally new approach to counteract the gravitational load of a mobile robot, namely, the expediency of equipping the robot with a source of reactive thrust of a non-chemical origin. A pneumatic generator of aerodynamic lift is proposed as such a source. Such a force partially compensates or completely overcomes the gravitational load, while not allowing the transformation of a mobile robot into an aircraft. The specified condition is necessary to perform contact power technological operations in the maintenance of various industrial facilities. In other words, the thrust force should not exceed the adhesion forces of the mobile robot to the displacement surface. As a research method, a full factorial experiment of the operation of a jet thrust generator was used, which is a new way to increase the reliability of holding the robot on an arbitrary surface. The article describes the methodology and description of the full factorial experiment with varying independent factors at two extreme levels. As a result, an experimental solution to the problem of finding the quasi-optimal values of the aerodynamic lifting force depending on the parameters of the jet thrust generator is obtained. As a result, the combination of a new robot design with the results of experimental studies confirms the feasibility of using a pneumatic jet thrust generator as a means of increasing the reliability of holding mobile robots on an arbitrary orientation surface in the technological space.

Experimental Studies on the Reactive Thrust of the Mobile Robot of Arbitrary Orientation

The problem of creating mobile robots of arbitrary orientation in the technological space is to ensure reliable retention of robots on the surface of any orientation. Therefore, well-known experimental studies are mainly devoted to the creation of systems for coupling the robot to the surface along which it moves. The purpose of this study is to create a device for compensating the gravitational load of a mobile robot. The article contains the results of experimental testing of a fundamentally new approach to counteract the gravitational load of a mobile robot, namely, the expediency of equipping the robot with a source of reactive thrust of a non-chemical origin. A pneumatic generator of aerodynamic lift is proposed as such a source. Such a force partially compensates or completely overcomes the gravitational load, while not allowing the transformation of a mobile robot into an aircraft. The specified condition is necessary to perform contact power technological operations in the maintenance of various industrial facilities. In other words, the thrust force should not exceed the adhesion forces of the mobile robot to the displacement surface. As a research method, a full factorial experiment of the operation of a jet thrust generator was used, which is a new way to increase the reliability of holding the robot on an arbitrary surface. The article describes the methodology and description of the full factorial experiment with varying independent factors at two extreme levels. As a result, an experimental solution to the problem of finding the quasi-optimal values of the aerodynamic lifting force depending on the parameters of the jet thrust generator is obtained. As a result, the combination of a new robot design with the results of experimental studies confirms the feasibility of using a pneumatic jet thrust generator as a means of increasing the reliability of holding mobile robots on an arbitrary orientation surface in the technological space.