Laboratory Bench Research Articles

IMPLEMENTATION OF A MATCHED FILTER FOR LFM SIGNALS USING A SYSTEM-ON-CHIP BASED SDR TRANSCEIVER

Background. Creation of communication channels with effective protection against intentional interference is the most urgent task for communication channels of unmanned aerial vehicles (UAVs). An effective solution is the use of signals with spectrum expansion, which allows reducing the impact of intentional interference on control and telemetry channels, thereby increasing the survivability of UAVs. The most optimal is the use of LCM modulation, which became possible with the development of SDR and SoC technologies. The main problem of using LFM modulation is the complexity of implementing matched filters. This requires research to create optimal digital implementations of matched filters. Objective. The purpose of the paper is to determine the parameters of the LFM signal for the implementation of the communication system using CSS modulation on the SDR transceiver. Optimal implementation of discrete matched filter (correlator) for CSS BOK modulation on FPGA (SoC). Methods. Analysis of the possibilities of implementing CSS BOK modulation for building a communication system based on SDR transceivers. Analysis of optimal options for building a discrete matched filter (correlator) for CSS BOK modulation on FPGA (SoC) and its implementation. Testing on a laboratory bench. Results The possibility of creating a communication system based on an SDR transceiver using CSS BOK modulation has been confirmed. The optimal parameters of the LFM signal, which can be implemented, have been studied. An implementation of a discrete matched filter (correlator) for CSS BOK modulation on FPGA has been developed. Testing carried out on a laboratory bench using SDR transceivers AD9361 (AD9364) showed the correctness and effectiveness of the decisions made. Conclusions The parameters of the LFM signal for the implementation in the communication system using CSS modulation on the SDR transceiver have been studied and determined. It was determined that when using the AD9361 (AD9364) transceiver, it is possible to implement an LFM signal with a band of up to 25 MHz, while the optimal symbol duration will be 16.6667 µsec at 1024 counts and a sampling frequency of 61.44 MHz. It was determined that the best CSS modulation method for creating a communication system is the binary orthogonal manipulation (BOK) method, which allows you to effectively use the advantages of SDR technologies, in particular, the ease of working with quadrature channels and, as a consequence, the ease of implementing phase synchronization. It has been determined that the best method of implementing a matched filter (correlator) on the basis of FPGA (SoC) is the application of fast convolution based on the fast Fourier transform. The developed implementation of a discrete matched filter (correlator) for CSS BOK modulation on FPGA showed the possibility of implementing a communication system with CSS BOK modulation on an SDR transceiver in full accordance with the research results. Experimental studies were carried out on a laboratory bench using SDR transceivers AD9361 (AD9364), which fully confirmed the results of simulation modelling.

Identification of the dynamic model of second-life lithium-ion cells through Subspace System Identification and similarity transformation

When lithium-ion batteries (LiBs) reach the end of their first useful life in electric vehicles (EVs), they can still be used in applications with lower power demands, a process known as second-life. However, to ensure that LiBs – or cells – removed from EVs operate safely, efficiently, and reliably in a second application, various tests and procedures must be applied to study their internal conditions. Some information about the conditions of the lithium-ion cells can be obtained from the parameters of its equivalent circuit model(ECM). However, the tests to obtain blackthe ECM parameters usually require taking the LiBs out of service and testing their cells in laboratory benches with special equipment, which is costly and time-consuming. Therefore, this work proposes a methodology to identify the ECM of lithium-ion cells based on Subspace System Identification (SSI) methods. This procedure can be executed online, while the LiBs are being used in the specified application. SSI methods have been widely adopted to identify the dynamic model of lithium-ion cells, but they return models without a physical meaning, called non-parametric models. This type of model cannot be used to address the internal conditions of a lithium cell, because its parameters do not have any physical meaning. To solve this problem, a novel method for estimating the lithium-ion cell physical parameters, in the ECM format, and from its non-parametric model, is proposed in this work. The procedure is based on similarity transformation techniques and special characteristics of the ECM. To validate the proposed method, nine samples of cells from the same manufacturer were studied. These cells had distinct degradation conditions and were removed from heavy-duty EVs at the end of their first life. The results showed that: (a) a good approximation between the identified model voltage output and the actual cells’ experimental voltage output was achieved, with root mean square error values as small as 2.26 mV; (b) it was possible to identify the ECM of the tested cells and their parameters using the proposed similarity transformation; and (c) the identified parameters can be used to detect the internal conditions of the cells.

Features of the operation of the training stand “Electric vehicle motor” in determining the operation characteristics of electric transport

In the modern world, the problem of the ecological state of our planet is acute. The environmental situation depends on many factors, these include both natural phenomena and human actions. One solution to this problem is to replace traditional internal combustion engines with more environmentally friendly electric vehicles.THE PURPOSE. The objective of this study is to analyze the internal structure of an electric vehicle, based on the training stand “Electric Vehicle Motor”, as well as to study the functions of this device, located at the Kazan State Energy University.METHODS. The authors of the article processed and analyzed the capabilities of modern laboratory equipment that simulates the operation of a particular component of an electric vehicle.RESULTS. The technology of the laboratory bench operating the electric vehicle, together with the DVT Customer software, allows for full control of the electric motor, as well as monitoring and changing a large number of parameters that affect the operation of the entire device as a whole.CONCLUSION. Since electric vehicles are gaining more and more popularity every year, the demand for people capable of diagnosing, repairing, and even improving existing ones and developing new components and assemblies in the field of electric vehicles is growing significantly. Using the “Electric Vehicle Motor” stand for teaching technical subjects and conducting research work can serve as a good basis for the formation of a general knowledge base about electric transport, its structure, the operating principle of all the main elements, monitoring and diagnostics of an electric vehicle.

Development and testing of a stand for studying the dynamics of an inertial screen with two motor-vibrators

Purpose. To substantiate the design of a stand for studying the dynamics of transient modes of an inertial screen with two motor-vibrators and to develop a methodology for conducting a physical experiment to study the dynamics of the screen. The methods. To conduct a physical experiment, a laboratory stand was developed to study the dynamics of screens. The bench consists of an inertial screen with a piezoelectric acceleration sensor KD 35-2, a system of laboratory devices for acoustic and vibration measuring equipment Robotron, and a computer with installed software. The obtained data are analyzed using software that allows to display graphs of oscillations in different directions: vertical, horizontal and at an angle of 45. Findings. A stand for analyzing the dynamics of screens was developed and tested. The results show that the computer modeling data and physical measurements are consistent. The maximum amplitude of vertical vibrations in the center of the screen was 24.71 mm, horizontal displacements reached 18.6 mm, and amplitude vibrations at an angle of 45° – 26.41 mm. The average deviation between the experimental and modeled data does not exceed 9%, which confirms the accuracy of the calculations. The originality. This study presents for the first time a laboratory testbed for studying the dynamics of inertial two-drive screens using piezoelectric sensors and the Robotron vibrometry system. The uniqueness of the work lies in the development of a laboratory bench that allows for accurate measurement of amplitudes in real time, as well as the comparison of results with data from models developed in SolidWorks. Practical implementation. The results of the developed methodology for studying physical prototypes of inertial double-drive screens can be used to optimize the design of vibrating screens in industry. The proposed approach makes it possible to accurately assess the dynamic characteristics of screens and determine the optimal parameters of their operation, which helps to reduce energy consumption and increase the efficiency of the material sorting process.

From lab bench to hope: a review of gene therapies in clinical trials for Parkinson's disease and challenges.

Parkinson's disease (PD) is a chronic neurological disorder that is identified by a characteristic combination of symptoms such as bradykinesia, resting tremor, rigidity, and postural instability. It is the second most common neurodegenerative disease after Alzheimer's disease and is characterized by the progressive loss of dopamine-producing neurons in the brain. Currently, available treatments for PD are symptomatic and do not prevent the disease pathology. There is growing interest in developing disease-modifying therapy that can reduce disease progression and improve patients' quality of life. One of the promising therapeutic approaches under evaluation is gene therapy utilizing a viral vector, adeno-associated virus (AAV), to deliver transgene of interest into the central nervous system (CNS). Preclinical studies in small animals and nonhuman primates model of PD have shown promising results utilizing the gene therapy that express glial cell line-derived neurotrophic factor (GDNF), cerebral dopamine neurotrophic factor (CDNF), aromatic L-amino acid decarboxylase (AADC), and glutamic acid decarboxylase (GAD). This study provides a comprehensive review of the current state of the above-mentioned gene therapies in various phases of clinical trials for PD treatment. We have highlighted the rationale for the gene-therapy approach and the findings from the preclinical and nonhuman primates studies, evaluating the therapeutic effect, dose safety, and tolerability. The challenges associated with gene therapy for heterogeneous neurodegenerative diseases, such as PD, have also been described. In conclusion, the review identifies the ongoing promising gene therapy approaches in clinical trials and provides hope for patients with PD.

An evidence-based review of Morinda citrifolia L. (Rubiaceae) fruits on animal models, human studies, and case reports

Context: Morinda citrifolia L. (Rubiaceae), commonly known as noni, is widely used as a complementary and alternative therapy in many countries due to its numerous beneficial effects on health. Aims: To thoroughly analyze the efficacy and safety of M. citrifolia fruit across all reported areas. Methods: The articles were explored on the PubMed and Cochrane Library databases using a combination of keywords: Morinda citrifolia AND human studies; Morinda citrifolia AND pharmacological activities using PRISMA guidelines. Results: Studies in animal models revealed its activity as anti-dyslipidemia, anti-lipogenesis, anti‑fungal, hepatoprotective, hypotensive, immunostimulatory, anti-alopecia, photoprotective, antitumor, antiviral, anticancer, antidopaminergic, and antimicrobial. Based on the clinical and efficacy evidence, it is apparent that M. citrifolia is a potentially valuable medicinal plant whose status should be upgraded from laboratory bench to bedside. The safety of M. citrifolia has been confirmed and proven by no occurrence of AEs or only mild gastrointestinal discomforts. However, five cases of male and female patients aged from 14 to 63 years old reported different symptoms, such as fatigue, headache, vomiting, pigmentation, or acute hepatitis, after a high-dose daily use of this supplement. Conclusions: Taking everything into consideration, M. citrifolia, despite its mild adverse events, has a beneficial efficacy and safety as an antioxidant; nevertheless, caution and therapy drug monitoring is required if this plant is to be taken in a long-term period.

Translational research: from the laboratory bench to the patient's bedside. Congenital heart disease: a window to knowledge

Translational research: from the laboratory bench to the patient's bedside. Congenital heart disease: a window to knowledge

Comparative near Infrared (NIR) spectroscopy calibrations performance of dried and undried forage on dry and wet matter bases

The application of Near Infrared (NIR) spectroscopy for analyzing wet feed directly on farms is increasingly recognized for its role in supporting harvest-time decisions and refining the precision of animal feeding practices. This study aims to evaluate the accuracy of NIR spectroscopy calibrations for both undried, unprocessed samples and dried, ground samples. Additionally, it investigates the influence of the bases of reference data (wet vs. dry basis) on the predictive capabilities of the NIR analysis. The study utilized 492 Corn Whole Plant (CWP) and 405 High Moisture Corn (HMC) samples, sourced from various farms across Italy. Spectral data were acquired from both undried, unground and dried, ground samples using laboratory bench NIR instruments, covering a spectral range of 1100 to 2498 nm. The reference chemical composition of these samples was analyzed and presented in two formats: on a wet matter basis and on a dry matter basis.The study revealed that calibrations based on undried samples generally exhibited lower predictive accuracy for most traits, with the exception of Dry Matter (DM). Notably, the decline in predictive performance was more pronounced in highly moist products like CWP, where the average error increased by 60–70%. Conversely, this reduction in accuracy was relatively contained (10–15%) in drier samples such as HMC. The Standard Error of Cross-Validation (SECV) values for DMres, Ash, CP, and EE were notably low, at 0.39, 0.30, 0.29, 0.21% for CWP and 0.49, 0.14, 0.25, 0.14% for HMC, respectively. These results align with previous studies, indicating the reliability of NIR spectroscopy in diverse moisture contexts.The study attributes this variance to the interference caused by water in 'as is' samples, where the spectral features predominantly reflect water content, thereby obscuring the spectral signatures of other nutrients. In terms of calibration development strategies, the study concludes that there is no significant difference in predictive performance between undried calibrations based on either 'dry matter' or 'as is' basis. This finding emphasizes the potential of NIR spectroscopy in diverse moisture contexts, although with varying degrees of accuracy contingent upon the moisture content of the analyzed samples. Overall, this research provides valuable insights into the calibration strategies of NIR spectroscopy and its practical applications in agricultural settings, particularly for on-farm forage analysis.

Effect of heating rate on the secondary reaction in low-rank coals pyrolysis with the real-time evolution analysis of in-situ tar

Performing online evolution analysis of tar in actual pyrolysis process is a major challenge. In this work, the effects of heating rate (HR) on evolution curves of in-situ tar for low-rank coals pyrolysis were investigated in a novel laboratory bench. The escape law of volatiles was obtained, the influence of HR on secondary reactions was analyzed, the association between products and molecular structures was constructed, and pyrolysis mechanism was deduced. Aliphatic hydrocarbons (except dienes), phenols, and oxygenated compounds have only one peak, while dienes and aromatics have multiple peaks throughout the pyrolysis process. The first peak is attributed to coal primary pyrolysis. At increased HRs, the second peak for 1∼2ring aromatics is from the cracking of primary volatiles, and that for 3∼4ring aromatics from coal continued cracking. The proportion of phenols and oxygenated compounds decreases, aromatics increases, and aliphatic hydrocarbons varies for different coals. Generally, HR increases the yield of primary volatiles by enhancing coal primary pyrolysis, elevates the proportion of light aromatics by promoting secondary cracking and aromatization of primary volatiles, reduces char yield by inhibiting condensation reactions throughout the pyrolysis process. The similar macromolecular structures of different coals make the evolution curve versus HRs follow a common law.

A Non-Destructive Study of Optical, Geometric and Luminescent Parameters of Active Optical Fibers Preforms

This work is devoted to the scientific and technical aspects of individual stages of active optical fibers preforms’ optical-geometric parameters metrological control. The concept of a system presented makes it possible to carry out a study of a rare earth element distribution in the preform of an active optical fiber and to monitor geometric parameters, and also to study the evolution of the refractive index profile along the length of the sample at a qualitative level. As far as it is known, it is the first description of the preform optical, geometric, and luminescent properties measurement within a single automated laboratory bench. Also, the novelty of the approach lies in the fact that the study of the refractive index profile variation along the length of the preform is, for the first time, conducted using the “dry” method, that is, without immersing the sample in synthetic oil, which makes the process less labor-intensive and safer.

Abstract IA012: Targeting AXL in platinum-resistant ovarian cancer: from the lab bench to Phase 3 trial

Abstract IA012: Targeting AXL in platinum-resistant ovarian cancer: from the lab bench to Phase 3 trial

Abstract 1773 From the lab bench to bedside, the importance of basic science research in medical education and beyond

Abstract 1773 From the lab bench to bedside, the importance of basic science research in medical education and beyond

Evaluation of some bio pesticidal plants in the management of Meloidogyne incognita

Utilization of compounds in extracts derived from medicinal plants is in vogue now for managing Meloidogyne incognita on crops owing to the unpopular use of synthetic nematicides especially in Sub-Saharan Africa. In this study, extracts from Azadirachta indica A. Juss and Hyptis suaveolens obtained using hexane, chloroform, ethyl acetate and methanol were tested for their efficacy in inhibiting egg hatching and inducing larval mortality of Meloidogyne incognita obtained from tomato bioassay maintained in Screenhouse. The extracts obtained from each solvent were reconstituted using Tween80+Dimethylsulfoxide (DMSO) and evaluated on hatching inhibition and larval mortality of Meloidogyne incognita at concentrations of 0.5%, 1.0%, and 1.5%. Furadan served as standard checks while distilled water and Tween80+(DMSO) as controls. Two separate experiments were conducted with 39 treatments each arranged in a Completely Randomized Design (CRD) with four repetitions on the laboratory bench for the hatching inhibition and larval mortality. Ninety (90) µL of each extract was added to 10 µL suspension containing either 15 eggs or second-stage larvae of Meloidogyne incognita pipette into cavity glass blocks. Hatching inhibition and larval mortality readings were recorded at 6, 12, 24, and 36 hours. Results indicated that Neem and Hyptis mixture at all concentrations extracted using any of the solvents gave 100% egg hatching inhibition from the 6th to the 36th h after treatment application. Only Neem and Hyptis mixture at 0.5% extracted in chloroform gave 100% larval mortality at the 6th h till the 36th h among the lowest concentration of the mixtures of the plant extracts. Combined solvent extracts of the two plants showed the highest activity in both hatching inhibition and larval mortality but individual solvent extracts showed the highest activity only at the highest rates used. The acute toxicity test of the most effective solvent extract of Neem and Hyptis at 0.5% extracted in Chloroform did not cause any sign of toxicity or death in the test animals.

Advances in making Mn oxide‐coated sands

AbstractManganese (Mn) oxide‐coated sand has been suggested as an amendment for scrubbing metals in water filtration beds and also as a less concentrated medium for uniformly amending soils with Mn oxides in mesocosm scale studies. Earlier work at the lab bench scale, using potassium permanganate (KMnO4) solutions that were reduced with sodium (Na) lactate, resulted in sands coated with about 0.13% Mn. The goal of this project was to increase the amount of Mn oxide that could be coated on sand to make it a more useful amendment and also to attempt to scale up the procedure to produce larger (kg) quantities of coated sand. Titration experiments examined the effects of (1) varying the molar ratio of Na lactate to KMnO4, (2) varying the rate at which the titration was accomplished, and (3) varying the concentration (molarity) of the original KMnO4 solution. The results of this work led to an optimal approach utilizing 0.32 M KMnO4 solution that was titrated to a final lactate:permanganate ratio of ∼1.1 with 10% of the lactate being added every 10 min while the suspension was being stirred. The proportion of sand to an initial solution was also increased 5–20 fold to between 50 and 200 g per 100 mL of solution. Applying this method and using a large 20‐ to 30‐L reaction vessel yields sands coated with up to 0.7% Mn in batches 5–10 kg is size, which could be useful as an amendment in mesocosm scale studies, or as a component of treatment filter beds. The examination of various size fractions of the coated sands demonstrated that more Mn was coated on finer sand fractions, which appears to be a function of the particle surface area available for the coating of Mn oxides, and at a rate of 0.3–0.5 µg Mn mm−2 of the particle surface.

Powering AI at the edge: A robust, memristor-based binarized neural network with near-memory computing and miniaturized solar cell

Memristor-based neural networks provide an exceptional energy-efficient platform for artificial intelligence (AI), presenting the possibility of self-powered operation when paired with energy harvesters. However, most memristor-based networks rely on analog in-memory computing, necessitating a stable and precise power supply, which is incompatible with the inherently unstable and unreliable energy harvesters. In this work, we fabricated a robust binarized neural network comprising 32,768 memristors, powered by a miniature wide-bandgap solar cell optimized for edge applications. Our circuit employs a resilient digital near-memory computing approach, featuring complementarily programmed memristors and logic-in-sense-amplifier. This design eliminates the need for compensation or calibration, operating effectively under diverse conditions. Under high illumination, the circuit achieves inference performance comparable to that of a lab bench power supply. In low illumination scenarios, it remains functional with slightly reduced accuracy, seamlessly transitioning to an approximate computing mode. Through image classification neural network simulations, we demonstrate that misclassified images under low illumination are primarily difficult-to-classify cases. Our approach lays the groundwork for self-powered AI and the creation of intelligent sensors for various applications in health, safety, and environment monitoring.

First report of root and crown rot caused by Fusarium oxysporum Schltdl. on Prunus cerasifera L. in Spain.

In 2021, Spain was the largest producer of cherries in Europe with a production of 125810 tons (FAOSTAT, 2021). In May 2022, in several production fields in Huelva (Spain), wilting was noted in 4-year-old cherry trees cv. Crystal Champaign grafted on rootstock cv. Adara (Prunus cerasifera L.). Gumming and wilting affected approx. 1% of the production area, leading to the eventual collapse and death of most affected trees within 2-3 years. Discoloration of the vascular system of the crown and roots was also noted. Symptomatic crown and root pieces (0.5 cm) were subjected to surface sterilization: immersed in 1% NaClO for 2 min, rinsed in sterile distilled water, and air-dried in a laminar flow cabinet. Then, plant tissues were placed on potato dextrose agar (PDA) amended with streptomycin and incubated in a lab bench at room temperature for a week. Cottony and pink colonies were observed growing from the tissues. Two single strains (F175 and F176) were obtained from each tree by excising single spores (Gordon and Okamoto 1991). Isolates produced sparse aerial mycelia with white to pinkish-orange pigmentation on Spezieller Nährstoffarmer Agar (SNA). Both isolates produced microconidia in false heads on short monophialides. Microconidia were hyaline and measured in the range of 5.0-17.5 × 2.5-3.8 µm for both isolates (n = 50). Macroconidia were less abundant, falciform, and hyaline. Morphological characteristics were consistent with identification as Fusarium spp. (Leslie and Summerell 2006). A portion of the translation elongation factor-1 alpha (EF-1α) gene was sequenced using EF1/2 primers (O'Donnell et al. 1998) (GenBank Accession Nos. OR733348 and OR733349). Based on a comparison of 619 base pairs (bp), both isolates exhibited different sequences, with a 99.5% similarity (616/619 bp). A comparison with previously described isolates revealed a 100% match with published F. oxysporum sequences in the GenBank database (KT323846 and MZ404079, respectively). Isolates were used to conduct pathogenicity tests on 1-year-old plants cv. Adara growing in 512 cm3 pots. Using a scalpel, a 6-7 mm-length wound (2-3 mm deep) was made 5 cm above the soil line in all plants. For each isolate, 5 plants were inoculated by placing a 5 mm plug containing 10-day-old mycelia grown in AMAP medium (Borrero et al. 2009) at the incision point. Non-colonized AMAP plugs were used to inoculate 5 control plants. The inoculated sites were sealed with parafilm. Plants were randomly placed in a growth chamber with a temperature of 28/24ºC and a 12-hour photoperiod. A reddish-brown vascular stem discoloration was noticed in all the inoculated plants 73 days after inoculation. On average, the length of the necrotic area was 12.73 cm for F175, 20.12 cm for F176, and 4.59 cm for the control plants. Fusarium oxysporum was successfully re-isolated from all the inoculated plants. Recovered isolates were confirmed to be the same as the inoculated ones by sequencing the EF-1α gene. A one-way ANOVA indicates that plants cv. Adara were susceptible to both F. oxysporum isolates (P < 0.05). This is particularly noteworthy as cherries are predominantly planted on rootstocks and cv. Adara is a widely used rootstock in Spain. While F. oxysporum has been reported as the cause of root and crown rot in sweet cherry (P. avium L.) in British Columbia (Úrbez-Torres et al. 2016), this is the first report of F. oxysporum causing root and crown rot in cherry rootstocks (P. cerasifera L.) in Spain.

Express barcoding with NextGenPCR and MinION for species-level sorting of ecological samples.

The use of DNA barcoding is well established for specimen identification and large-scale biodiversity discovery, but remains underutilized for time-sensitive applications such as rapid species discovery in field stations, identifying pests, citizen science projects, and authenticating food. The main reason is that existing express barcoding workflows are either too expensive or can only be used in very well-equipped laboratories by highly-trained staff. We here show an alternative workflow combining rapid DNA extraction with HotSHOT, amplicon production with NextGenPCR thermocyclers, and sequencing with low-cost MinION sequencers. We demonstrate the power of the approach by generating 250 barcodes for 285 specimens within 6 h including specimen identification through BLAST. The workflow required only the following major equipment that easily fits onto a lab bench: Thermocycler, NextGenPCR, microplate sealer, Qubit, and MinION. Based on our results, we argue that simplified barcoding workflows for species-level sorting are now faster, more accurate, and sufficiently cost-effective to replace traditional morpho-species sorting in many projects.

Statistical process control in pulsed drip irrigation systems

Pulse drip application is a management option to prevent clogging and improve water-use efficiency. The measurement of distribution uniformity is opportune for pulse irrigation projects to ensure efficiency since the shorter the pulse time, the more negative influence the transition periods have. The objective of the present work was to monitor the quality of a drip irrigation system with different emitter models and different pulse times. The experiment was conducted under laboratory bench conditions, and 25 tests were performed for each pulse application (2, 3, 6 and 12 minutes) and emitter model (non-compensated and auto-compensated). Uniformity was determined using Christiansen's uniformity coefficient (CUC) and distribution uniformity coefficient (DUC) and monitored by Shewhart control charts and exponentially weighted moving average (EWMA). The decrease in pulse time caused a decrease in flow rate and uniformity only in drip irrigation systems with non auto-compensated emitters. However, this decrease is subtle, to the point that uniformity presented an excellent performance for all pulses tested. The use of the Shewhart and EWMA control charts were effective in monitoring the uniformity of the pulsed drip irrigation system. The Shewhart control chart was more robust in identifying isolated non-compensated uniformities, while the EWMA control chart was more sensitive in identifying unstable propensity. In the treatments with the non-compensated emitter, the statistical process control was able to identify that shorter pulse times resulted in greater application instability. As for the auto-compensated emitters, the statistical process control highlighted the concern with application uniformity after maintenance interference.&#x0D; Keywords: anti-drain emitter, high-frequency irrigation, irrigation interval, statistical quality control.

МЕТОДИКА ЭКСПЕРИМЕНТАЛЬНОГО ИЗУЧЕНИЯ ПРОЦЕССА ТЕПЛООБМЕНА С ИСПОЛЬЗОВАНИЕМ ИМИТАЦИОННЫХ МОДЕЛЕЙ В РЕАЛЬНОМ ВРЕМЕНИ

The laboratory installation “Study of heat transfer in a pipe-in-pipe heat exchanger with a storage water heater” was supplemented with a digital component that meets the modern level of information technology. The laboratory bench was equipped with new digital temperature and flow sensors. Temperature sensors are installed at the inlet and outlet of coolants. An arduino uno controller is installed to collect data from sensors, perform primary processing and send information to the computer. To visualize sensors data, a program was written in the julia programming language. The program displays 6 figure. Two figures demonstrate the change in the quantities measured by the sensors (temperatures and flow rates) over time. The remaining figures show the calculated values. Based on temperatures and flow rates of coolant, the change in heat flow over time is calculated. Based on the heat flow and the average driving force, the heat transfer coefficient is calculated, calculated from the thermal loads calculated from the hot and cold coolant. Based on a large number of experiments, a criterion equation for calculating heat transfer coefficients for hot and cold coolants was obtained. The change in heat transfer coefficients over time is also demonstrated in program. To understand the processes occurring inside the heat exchanger, the temperature change along the length of the heat exchanger is also shown on the screen. Temperature profiles are calculated based on solving the differential equation for the plug-flow model. The heat transfer coefficient values are calculated using the founded criterion equations. Upon completion of the experiment, the accumulated data is sent to the web server and it is available to students via a link that is shown as a qr code in the program window. The web server determines the areas of stationarity and processes the results according to the methodological instructions for the students. The results of processing are available to the professor and facilitate the search for errors and inaccuracies in the calculations carried out by the student.

METHODOLOGY FOR STUDYING THE COMBUSTION OF SOLID AND LIQUID SUBSTANCES A CLOSED VOLUME

The development of new methods for testing substances and materials is a relevant area that allows to assess the fire hazard of substances, including modern materials, the composition of which is constantly improving and changing. There are and are created special conditions in the premises, under which combustion acquires a completely different character. An example of such conditions can be combustion in a closed volume, when there is no oxygen access and no energy exchange with the environment. We present a technique that allows us to study the combustion of solids and liquids in a closed volume and to control the parameters of the gas medium. The purpose of the technique is to study the kinetics of combustion of solids and liquids in a closed volume by controlling the parameters and investigating their influence on each other (temperature of the gas medium, reduction of light transmission of combustion products, total oxygen concentration, mass loss of samples). A description of the three stages and the order of their realization is given. The laboratory bench developed by the author is briefly described. The results of the research are supposed to be used to expand the understanding of the nature and kinetics of combustion of substances and materials in a closed volume, as well as to assess the fire hazard of substances whose combustion can occur in a closed volume.