bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper-catalyzed one-pot [3 + 2] cycloadditions of ethynyl indoloxazolidones with 1,3-cyclohexanediones
Authors: Su Qing-Qiang , Wang Ruo-Nan , Lv Yong-Zheng , Fan Ya-Xin , Li Shan , Huang Hong-Li , Du Ji-Yuan
Published: April 2023

Efficient copper-catalyzed [3 + 2] cycloadditions of ethynyl indoloxazolidones with 1,3-cyclohexanediones to access functionalized furan derivatives under mild conditions.
From citronellal to iridoids: asymmetric synthesis of iridoids and their analogues via organocatalytic intramolecular Michael reactions
Authors: Tammisetti Raviramanujayya , Chaudhari Prakash D. , Hong Bor-Cherng , Chien Su-Ying
Published: April 2023

A series of iridoids and their analogues have been synthesized efficiently from citronellal via the key-step reaction of metathesis, organocatalysis, and subsequent transformation.
3D-printed ketoenamine crosslinked polyrotaxane hydrogels and their mechanochromic responsiveness
Authors: Zheng Dan , Tang Miao , Ke Chenfeng
Published: April 2023

We report the synthesis and 3D printing of mechanically robust ketoenamine-crosslinked polyrotaxane hydrogels. These hydrogels are tagged with molecular probes to show fluorescent emission changes upon compression.
Dancing silanols: stereospecific rearrangements of silanol epoxides into silanoxy-tetrahydrofurans and silanoxy-tetrahydropyrans
Authors: Joshi Harshit , Thomas Annu Anna , Mague Joel T. , Sathyamoorthi Shyam
Published: April 2023

We have developed highly stereospecific rearrangements of silanol epoxides into 1′-silanoxy-tetrahydrofurans and 1′-silanoxy-tetrahydropyrans.
Heterogeneous photochemical reaction enabled by an ultrasonic microreactor
Authors: Udepurkar Aniket P. , Nandiwale Kakasaheb Y. , Jensen Klavs F. , Kuhn Simon
Published: April 2023

A novel ultrasonic microreactor is demonstrated for the heterogeneous silyl radical-mediated metallaphotoredox cross-electrophile coupling.
Structural and biochemical analysis of a novel atypically split intein reveals a conserved histidine specific to cysteine-less inteins
Authors: Pasch Tim , Schröder Alexander , Kattelmann Sabrina , Eisenstein Miriam , Pietrokovski Shmuel , Kümmel Daniel , Mootz Henning D.
Published: April 2023

Cysteine-less split inteins are very useful, but rare tools for protein engineering. Investigation of the novel PolB16 intein revealed a previously overlooked histidine as a conserved part for the serine-dependent mechanism.
Ruthenium-catalysed decarboxylative unsymmetric dual ortho-/meta-C–H bond functionalization of arenecarboxylic acids
Authors: Li Xiankai , Wang Xiaofei , Zhang Jing
Published: April 2023

We report a Ru-catalysed decarboxylative unsymmetric ortho-C–H azaarylation/meta-C–H alkylation via a traceless directing group relay strategy, which shows high regio- and chemoselectivity with broad substrate scopes under redox-neutral conditions.
Molecular-level insights into a tripolyphosphate and pyrophosphate templated membrane assembly
Authors: Prasad Mahesh , Hazra Bibhas , Sardar Avijit , Mandal Raki , Gayen Soumajit , Tarafdar Pradip K.
Published: April 2023

Templated assembly of amphiphiles into nano-structural architectures has been used extensively by nature throughout its evolution.
Macroscopic analogue to entangled polymers
Authors: Gómez Leopoldo R. , García Nicolás A. , Pöschel Thorsten
Published: April 2023

X-ray tomography helps us study complex macroscopic entangled structures and to verify that systems like noodles, earthworms, snakes, and rubber bands can indeed be a good approximation of real polymers.
Hybrid domain digital watermarking scheme based on improved differential evolution algorithm and singular value block embedding
Authors: Liu Dawei , Liu Donglin , Wang Bin , Zheng Pan
Published: April 2023

The internet and related technologies have promoted the development of medical and health fields, especially remote diagnosis. As medical images may be stolen in the transmission process, the patient's personal information could be leaked. Aiming at the problem of privacy disclosure of colour medical images, a hybrid domain watermarking scheme based on improved differential evolution (DE) and the singular value block embedding (SVBE) is proposed in this study. Through this scheme, the image containing the patient's information is hidden in the patient's medical carrier image as a watermark. First, redistributed invariant lifting wavelet transform (RILWT), discrete wavelet transform (DWT), and singular value decomposition (SVD) are used to process the colour medical carrier image, and the high‐frequency information in the integer wavelet domain of the watermark is embedded into the processed carrier image using the proposed singular value block embedding method based on the improved differential evolution algorithm. At the same time, to increase the security of the watermark scheme, a digital signature based on the SHA‐384 hash function is designed for verification before watermark extraction. Compared with recent related research, the scheme has strong invisibility and robustness.
Design of on‐chip antennas for THz detector and source in CMOS (Invited paper)
Authors: Xu Lei‐Jun , Zhao Xin‐Ke , Bai Xue
Published: April 2023

Different on‐chip antennas in Complementary Metal‐Oxide‐Semiconductor (CMOS) technology for THz detector and source are proposed. Firstly, the size of these antennas is estimated with an equivalent CMOS substrate model. Finally, through electromagnetic simulation, the structure optimised and slotted the on‐chip antenna to realise multi‐band detection, miniaturised detection, and miniaturised source. For the THz detector, multi‐band antennas with a dual‐ring structure and miniaturised antennas with circular and diamond structures are designed. At the frequency of 300, 600, and 800 GHz, the gain of the ring antennas is 5.7, 7.2, and 7.2 dBi, respectively. The gain of the circular and diamond antenna is 5.3 and 5.96 dBi at 300 GHz. For the THz source, rectangular‐slot and T‐slot antennas are designed at the frequency of 300 GHz and the gain of the rectangular‐slot and T‐slot antennas is 2.92 and 3.87 dBi, respectively. Multi‐band antennas and miniaturised antennas effectively save the occupation area and improve the performance of the THz system. The effectiveness of antennas is verified by the measurement of the detector and the source, which indicates that the proposed on‐chip antennas have potential prospects for CMOS THz applications.
IoT applications and challenges in smart cities and services
Authors: Rafiq Iqra , Mahmood Anzar , Razzaq Sohail , Jafri S. Hassan M. , Aziz Imran
Published: April 2023

Internet of Things (IoT) is a revolutionary and novel platform where a smart network connects to the large number of electronic devices via internet through available communication systems for reliable and real time connectivity, sensing thus acquiring data from sensors, computing and actuating devices. A review of the current status of IoT features, architecture, communication infrastructure and applications is presented here. Number of IoT applications and challenges in the development of smart cities are covered about this innovative technological platform in this review along with communication protocols characteristics and applications. IoT aided smart city services, health applications, transport applications and smart grid improvements are also discussed. Many challenges and issues related to security, communication, applications and system architecture along with future directions of IoT technology are elaborated in detail.
Adaptive overcurrent relay (AOCR) based on Fano Factors of current signals
Authors: Mahmoud Ragab Abdallah , Malik Om Parkash
Published: April 2023

A Fano Factor‐based adaptive overcurrent protection scheme, that automatically adjusts the protection settings in response to the prevailing conditions of the power system, is presented. Both phase and ground overcurrent relays are based on the same mathematical algorithm to calculate the operating time using Fano Factors (FFs) estimated for phase and ground current signals, respectively. Effectiveness of the proposed adaptive overcurrent method is validated for various fault types under a plethora of loading current levels, besides a wide range of fault inception angles and fault resistance. Simulation results confirm that the proposed algorithm can detect series and shunt faults, differentiate between grounding and phase faults, and adapt the relay operating time settings using the FF for all conditions examined. The relay algorithm speed and sensitivity are controllable using both the FF setting values and moving data window size. Moreover, it is characterized by being simple, reliable, accurate, and can be implemented practically as a base of digital protective relay for use in substation automation systems and phasor measurement units.
Experimental observation and constitutive modelling of the shear strength of a natural unsaturated soil
Authors: Chao Ching-Yu , Muraro Stefano , Broere Wout , Jommi Cristina
Published: April 2023

Increasing frequency and intensity of extreme weather events in the Netherlands is raising attention on the unsaturated response of geo-infrastructures, promoting research projects to provide an overview of the impact of unsaturated conditions on the response of shallow soil layers and embankments, and to better address maintenance and mitigation measures. As part of this effort, we discuss the results of standard laboratory tests performed on initially unsaturated samples retrieved from the field and tested in natural conditions, as well as after controlled drying and wetting. The variation of the “undrained” (i.e. at constant water content) shear strength with the degree of saturation obtained from the laboratory tests aligns well with CPT measurements performed in the field. An elastic-plastic constitutive model with mixed isotropic-rotational hardening developed for saturated soft soils was extended to unsaturated conditions by following a robust approach previously developed for compacted clayey soils. Coupling between the mechanical and the hydraulic behaviour is provided by the water retention curve. The model nicely captures the response observed in the laboratory, until extreme dry conditions, which possibly alter the structure of the soil, the peak stress, and the brittleness after failure. The model is capable of reproducing the effects of the previous hydraulic history on the stress-strain behaviour observed from the laboratory tests over a wide range of degree of saturation.
Constant void ratio vs. constant confining pressure tests on partially saturated silty soil
Authors: Ahmad Tufail , Kato Riko , Shrestha Dipak Raj , Kuwano Jiro
Published: April 2023

The presence of soil solids, water, and air complicates understanding unsaturated soil dynamics. A thorough understanding of unsaturated soil behavior is essential for the fruitful design of slopes, embankments, and retaining structures. A series of constant void ratio and constant confining pressure triaxial compression tests were carried out under constant water content conditions (pore air pressure drained and pore water pressure undrained) to study the shear strength and deformation characteristics of a partially saturated silty soil. Test specimens were prepared with a water content of 15%, 20% (Optimum water content), and 25%, with the corresponding degree of saturation of 37, 49, and 62.5%. The degree of compaction of all specimens was kept at 83% while the dry density was 1.29 g/cm3, and the void ratio was around 1.045. All the samples were isotropically consolidated under 500kPa by keeping deviatoric stress at 0kPa. The constant void ratio test results showed that the deviatoric stress reached a peak value followed by a sudden decrease within the axial strain of 0-1.5%. In contrast, the deviatoric stress increased continuously until reaching the critical state without depicting any peak for constant confining pressure tests. However, in both cases, the lower the water content at the time of specimen preparation, the higher the shear resistance.
Interpretation of constant suction direct shear test
Authors: Bulolo Sam , Leong Eng-Choon
Published: April 2023

Constant suction direct shear test enables the understanding of the failure mechanism in rainfallinduced landslides. It can be conducted using a conventional direct shear apparatus with some modifications. The constant suction direct shear test is carried out in two stages. In the first stage, the unsaturated soil specimen is consolidated to the target net normal stress and matric suction then sheared in the second stage. Matric suction is usually controlled using the axis-translation principle. It is commonly observed that the shear stress of an unsaturated soil sheared in the direct shear shows a strain-hardening behaviour at large displacements making the determination of the failure stress difficult. Hence, the objective of this study is to critically examine the constant suction direct shear tests and the analysis of the test results to obtain the shear strength parameters for unsaturated soils. Constant suction direct shear test data were collated from the literature. It was found that the interpretation of the direct shear test has two inconsistencies: (1) taking failure shear stress at arbitrary displacement strain or limit, dependent on the size of the direct shear apparatus, and (2) correcting only shear stress for contact area. The effect of these two consequences on the interpretation of the direct shear test range from negligible to significant. The study shows that arbitrary determination of failure shear stress can be resolved by plotting the direct shear test results using a stresspath plot. The effects of area correction are shown to be almost negligible for small horizontal displacements of less than 2 mm for both square and circular shear boxes. A more consistent interpretation of the constant suction direct shear test is demonstrated where both these inconsistencies are considered.
Effects of microstructure on THM behaviour of geomaterials
Authors: Pereira Jean-Michel
Published: April 2023

In this paper, we discuss the thermo-hydro-mechanical behaviour of geomaterials at the light of their microstructure and its changes induced by multiphysics loading. After recalling the strong links between the microstructure and the water retention properties of unsaturated soils, the relation between themicrostructure and the physical properties ruling heat and mass transfers are discussed. The mechanical behaviour of unsaturated soils is then discussed focussing on the definition of an effective stress based on a microstructure description. The experimental determination of this microstructurally-based effective stressis presented, including recent advances to identify the stress coefficient from Mercury Intrusion Porosimetry data. Opening remarks towards macroscopic modelling of unsaturated geomaterials accounting for their microstructure and its changes is finally discussed.
Analysis of transient seepage through a river embankment by means of centrifuge modelling
Authors: Ventini Roberta , Dodaro Elena , Giretti Daniela , Pirone Marianna , Zarattini Francesco , Gragnano Carmine Gerardo , Fioravante Vincenzo , Gabrieli Fabio , Gottardi Guido , Mancuso Claudio
Published: April 2023

Earthen river embankments are typically in unsaturated conditions during their lifetime and the degree of saturation within their bodies may vary significantly throughout the year, due to seasonalfluctuations of the river stage, as well as infiltrations of meteoric precipitation and evapotranspiration phenomena. Given the significant effects of partial saturation on the hydro-mechanical behaviour of soils, realistic assumptions on the actual water content distribution inside the embankments are essential forproperly modelling their response to hydraulic loadings. In this framework, centrifuge modelling is a useful tool to get insights into the evolution of saturation conditions of a water retaining structure during flood events. It allows for the direct observation of the groundwater flow process, which is hardly detectable at the prototype scale, enabling, at the same time, the validation and calibration of predictive numerical tools.In this paper, the results of a centrifuge test carried out on small-scale physical model of a compacted silty clayey sand embankment subjected to a simulated high-water event, at the enhanced gravity of 50-g, are presented and discussed. The physical model was carefully instrumented with potentiometers, miniaturized pore pressure transducers and tensiometers. Pore pressures and suctions measured during the experiment showed that the stationary flow conditions were reached only after an unrealistic hydrometric peak persistence. It therefore emerges that, for the design and/or the assessment of the safety conditions of a river embankment similar to the one tested, the simplified hypothesis of a steady-state seepage, in equilibrium with the maximum river stage expected could result, in many cases, an excessively conservative assumption.
Impact of sand on the water retention properties of a bentonite/sand mixture by NMR characterization
Authors: Eizaguirre Pablo , Tang Anh Minh , Maillet Benjamin , Sidi-Boulenouar Rahima , Chabot Baptiste , Bornert Michel , Pereira Jean-Michel , Dangla Patrick , Aimedieu Patrick , Talandier Jean , Vu Minh Ngoc
Published: April 2023

Blocks of compacted bentonite/sand mixture, with a 40/60 proportion in dry mass, are being studied as an elementary component in the construction of seals in the French concept for high-levelradioactive waste disposal. In the disposal, the seal will be subjected to water infiltration from the host rock. Water retention behaviour in the mixture is governed by bentonite. Nevertheless, the impact of the sand fraction, especially at high concentrations, is still unclear. The water retention curve is found experimentally for the wetting path by using vapour equilibrium technique. Moreover, NMR relaxometry tests executed atfull saturation state are presented. As a result of the comparison with experimental data reported in the past, for different mixtures -ranging from pure bentonite to 20/80 bentonite/sand mixtures-, it is concluded that all porosity in the mixture can be correctly attributed to bentonite. This conclusion simplifies mixtures to equivalent pure bentonite specimens with a dry density equal to the bentonite dry density (𝜌𝑑,𝑏) of the mixture. Moreover, an original method to compare NMR relaxation times for different bentonite/sand -or pure bentonite- mixtures is proposed. It provides the longitudinal relaxation time (T1) in saturated mixtures as a function of 𝜌𝑑,𝑏 and the montmorillonite concentration in bentonite.
Capillary Barrier Effect in an Earthen Roof of Historical House
Authors: Aslan Fidan Aysenur , Berilgen Mehmet Muhit
Published: April 2023

A capillary barrier is a widely used drainage system in recent years. It has been in practice since the end of the 1950s, and research over the past 60 years has provided valuable insight into its safe and economical design. Although capillary barrier application is not an old and traditional technique, it is possible to see its primitive application on earthen roofs of traditional buildings. One of these applications is in the earthen roofs of historical and protected houses in Kemaliye district in eastern Turkey. In this study, the capillary barrier behaviour of the earthen roof system of historical Kemaliye houses, which has existed for centuries, has been experimentally investigated. In this context, soil index properties and water characteristic curves were determined by conducting laboratory experiments on samples taken from the soil roof of a traditional Kemaliye house. In order to examine the capillary barrier behaviour of the roof in precipitation, 1D model infiltration experiments were carried out. In the light of the findings obtained from these experiments, it was concluded that the earthen roofs of traditional Kemaliye houses show varied capillary barrier behaviour depending on the initial conditions of the layers.
Field observations of soil moisture, suction and movement of cornfield in tropical highland with and without vetiver system
Authors: Jotisankasa Apiniti , Jamrueang Wichuda , Pramusandi Sony , Semmad Surat , Pilumwong Jarunee
Published: April 2023

An increasing large number of cornfield have been cultivated in highland of many Southeast
Asian countries. In most cases, this corn plantation is done without proper soil & water conservation such as vetiver system (VS), thus causing land degradation and shallow slide. This study is aimed at investigating the field behaviour of slopes with corn plantation with and without vetiver system in Chiang Mai, Northern Thailand. Tensiometers, soil moisture sensors, in-place inclinometers and tiltmeters were installed at a slope in two locations, with and without vetiver system from surface to 2m depth. The monitoring results show that for the vetiver treatment, the soil moisture tended to be higher and response faster to rainfall than the cornfield without vetiver. However, the pore-water pressure in the root zone (about 0.5m) was higher for the vetiver treatment than the cornfield which only has the root depth of about 0.2m. For cornfield without vetiver, the seasonal variation of the soil moisture and pore-water pressure was also larger. Tiltmeter indicates a larger surface movement in the cornfield without VS. However, the inclinometer readings suggested that for slope with VS there was some cyclic movement toward hillside at the surface. This could be an indication of non-uniform settlement of soil layers or influence of groundwater rising.
The hydromechanical behaviour of unsaturated loess in slopes, New Zealand
Authors: Yates Katherine , Russell Adrian
Published: April 2023

Unsaturated loess and loess-derived soils in the Akaroa harbour area of New Zealand are vulnerable to shallow landsliding during rainfall events. Laboratory testing and long-term field instrumentation has been conducted to characterise the water retention and unsaturated shear strength of these materials, and better understand temporal changings in slope stability. Laboratory test results indicate that the same soil-water characteristic curve can be applied to both recompacted and intact loess when suction is normalised by the air entry value. Conversely the stress-strain behaviours of the recompacted and intact loess were different due to the unique microstructure of the intact loess that contributes to its shear strength. Long-term field instrumentation data showed that, for the duration of the monitoring period, the hydraulic state of the loess remained on a scanning curve. These data, combined with the laboratory testing, confirm that temporal variation in slope stability can be attributed to seasonal variability in suction and its contribution to unsaturated shear strength. These hydromechanical variabilities, resulting from wetting and drying, are affected by rainfall intensity and duration that occurs at the site.
Modelling a hydration and heating column test on unsaturated bentonite using a double-porosity approach
Authors: Vasconcelos Ramon , Gens Antonio , Vaunat Jean , Rodríguez Carlos E. , Villar Maria V.
Published: April 2023

A controlled re-saturation of a heated 50 cm long column made of MX-80 bentonite pellets in the CIEMAT laboratory facilities (Madrid, Spain) has been running for 10 years (2011-2021). The experimental data on the saturation state and the swelling response of the bentonite material at high temperatures provided useful information for the verification of a double-porosity approach that considers the hydro-mechanical coupling between the micro- and macro-pore levels and the definition of retention curves for each structural domain. The numerical modelling with this double-porosity model has shown to be able to reproduce the main behaviour features observed in the lab test.
Quantum computing in controlling railroads
Authors: Khomonenko Anatoly , Khalil Maad M.
Published: April 2023

The paper discusses the main possibilities of using quantum computing and technologies in railway management, highlighting the most promising options and proposals for their application. One of the main objectives of the RZD "Russian Railways" is the research and implementation of quantum telecommunications as the basis for building promising network services. By focusing on improving solutions in the field of automation of railway transport process management, and taking into account the over-growing and changing needs of customers, RZD also wants to trans-form to digitalization and use quantum computing to create flexible management models, optimization of the structure and decision-making processes and the use of quantum computers both in information systems and in technical control systems. The study first identifies areas where the development of information technologies in railway transport is a must. Then the strategies and programs to digitalis these fields are discussed, how they are implemented is shown and finally a comparison is then made with other experiences from different agencies around the world. The Study concludes that the creation of quantum information systems with a contactless neuro-computer interface will solve several problems like the performance of duties by railway personnel, monitoring of significant objects of critical information and technical infrastructure, and public services. It is advisable to use quantum technologies and calculations in railway transport in the following main directions: the creation of a quantum telecommunication network; the introduction of quantum computing in the improvement of Blockchain technologies; use of quantum technologies to solve complex optimization problems.
Methods for calculating and analyzing the capacity of a railway line with mixed traffic
Authors: Marchenko M. , Pokrovskaya O. , Rodneva E.
Published: April 2023

This paper considers methods of determining the capacity of railway lines with mixed traffic. This issue is relevant, since the calculation with the help of standard analytical formulas often does not correspond to the actual existing capacity of the railway line. In connection with this circumstance, the paper considers the method of calculating the capacity of the railway line using simulation modeling, the results of which are closer to the real values of the available capacity.
Retracted Article: Mathematical model for optimising drive suspension of a conveyor with suspended belt and distributed drive
Authors: Scherbakov Alexander , Breskich Vera , Deniskina Galina , Kharlamov Evgeniy
Published: April 2023

This paper has been formally retracted on ethical grounds because the article contains
extensive and repeated instances of plagiarism. The authors are responsible for this
mistake and apologise for it. Request approved by the proceedings Editor and the
Publisher on September 13, 2023.
Wastewater temperature changes in sewer outlets under severe climatic conditions
Authors: Terekhov Lev , Tvardovskaya Nadezhda , Mayny Shonchalay
Published: April 2023

Sewer outlets from buildings in a harsh climate are considered one of the main elements of the sewer network, determining its reliability and efficiency. The article considers the change in the temperature of wastewater at sewer outlets laid at a reduced depth in the frozen ground. Methods: The purpose of this study was to determine the temperature of wastewater at the sewer outlets in the city of Kyzyl during the day in winter. Result: New experimental data on wastewater temperature are presented and summarized. The range of change in the temperature of wastewater at the sewer outlets from the building in the city of Kyzyl has been determined. The results of measurements of a full-scale experiment during the day in winter are presented.
The role of agile+bim+tunnel innovation in ensuring economic efficiency and security on backbone infrastructure expansion
Authors: Shestakova Ekaterina , Kazaku Ekaterina , Shestakov Pavel
Published: April 2023

This article explores the key lean and safe technologies used for unique transportation projects to expand highway infrastructure. Given today's digital requirements, there are trends to reduce time, cost, and safety, but all of this is possible by introducing several key innovations into the design and construction process. New lean BIM technologies, methods of adaptive flexible Agile-approach have completely transformed modern design technologies and with the application of safe work, methods allow not only to carry out safe reconstruction of transport facilities but also to act as a high-tech locomotive of the transport industry, capable of making a significant contribution of lean production for innovative development of the Eastern polygon. The main task of the reconstruction as a modern intensive ecologically safe production of construction works is necessarily considered with efficient resource consumption and nature management. The authors conclude that the reconstruction of BAM tunnels acts today as the main direction and sets a vector of innovation in the field of investment and innovation projects. Improvement of design activity and presented collective work of specialists of technical and economic specializations of PSUPS of two faculties in the field of tunnel reconstruction should be rightfully named as a prospective resource of economic development in the field of transport construction. The main project technologies under consideration in the innovation aspect: Agile+Bim, economic innovations on the choice of optimal strategy taking into account risk and uncertainty for scenario analysis by Monte-Carlo simulation method, technological innovations using the specialized technological complex for tunnel reconstruction.
Equalization of free geodetic networks by search methods for geodetic monitoring of structures in arctic areas
Authors: Shevchenko Grittel , Bryn Mikhail , Bushuev Nikolay
Published: April 2023

While carrying out work to ensure the technical safety of buildings and structures in the Arctic regions, one of the important stages is geodetic monitoring. Provided that the complexity of ensuring the stability of reference points in the Arctic zone when conducting geodetic monitoring of engineering facilities, geodetic networks should preferably be equated as free, i.e., to equate the reference points on a par with the defined ones. The present article provides variants how to to equalize geodetic networks to carry out a search method of non-linear programming, which is given a theoretical substantiation for the method and the order of estimating accuracy of the outcomes of the equalization of the generalized Makarov method. The procedure of pseudo transformation of a matrix of normal equations of unknowns with the application of an algorithm of a search method of nonlinear programming is given. The correctness of the application of the search method to the pseudo transformation of a matrix of normal equations of unknowns by the coincidence of outcomes of the pseudo transformation of the given matrix based on skeleton expansion done in M. Mashimov's work is proved. Equalization and estimation of accuracy of free leveling network with the application of search method and generalized Makarov's method are carried out. The conclusion about the correctness of the application of a search method of nonlinear programming for the processing of free geodetic networks at the performance of geodetic monitoring of buildings and constructions in the Arctic area is made.
Smart technologies for determining water flow in irrigation systems
Authors: Sapaev J. , Arifjanov A. , Ramazonov Kh. , Sapaev I.B.
Published: April 2023

Without the need for hand-coding, Machine Learning helps systems to enhance and develop dynamically from their experiences. As a result, numerous tech firms have been creating Artificial Intelligence applications in recent years. The majority of irrigation systems available today allow customers to program them to provide a specified amount of water at specific times. On the other hand, a garden frequently has a variety of plants, each of which needs a varying amount of water. This research planned an irrigation system that uses deep learning to regulate the quantity of water given to each type of plant based on plant identification to address this problem. The software and hardware are the two primary constituents of the technology. The former is linked to cameras for plant identification and uses a database to determine the appropriate amount of water; the other regulates the amount of water that can flow out. The technology is designed to predict how long to water the plants after discovering the perfect soil moisture with the applications and incorporating it with the outcome of the existing soil moisture level with the Arduino. This will allow the program to modify the software in the irrigation system controller to alter the period of time the regulator should be kept open.
Digital ecosystem and computer engineering
Authors: Lutsenko M. , Podkletnov S.
Published: April 2023

The present research paper regards the importance of the discipline of computer engineering for creating an ecosystem of transport and logistics services. Special attention is paid to modern knowledge control systems and, in particular, testing when assessing the level of knowledge of students. The variants of tasks prepared by the authors for the Moodle distance learning system are given. Modern systems for processing test results based on the theory of parametrization of Birnbauer-Rasch tests (Item Response Theory) are discussed. The results of testing of students in the discipline “Computer Engineering” at PSUPS are discussed.
The economic category of time in the context of the analysis of transport projects: theoretical aspects and assessment tools
Authors: Romanov Alexey
Published: April 2023

Research background: Swedish economist S.B. Linder considered time as the rarest resource, for the preservation of which people are willing to pay more and more. The problem of monetized evaluation of the benefits of reducing travel time has been relevant for the transport economy since the 1960s. The article is devoted to the study of the specifics of the time resource in modern socioeconomic systems and the analysis of approaches for assessing the benefits of changing time costs. Purpose of the article: To make a retrospective analysis of the phenomenon of time in economics, to investigate the evolution of methodological approaches to the assessment of time resources, to uncover contradictions between the fundamental ideas about the distribution of time resources and methods for assessing the benefits of changes in time costs. Methods: The methods of systematic, retrospective and comparative analysis are used in the paper. Findings & Value added: The conclusions obtained in the course of the study allow us to expand and concretize the methodology of economic assessment of transport projects. There are identified and systematized factors that determine the need for differentiated accounting of changes in the value of reducing travel time for passengers, which ultimately determines the demand for transport services.
Cargo delivery management in global supply chains under sustainable development conditions
Authors: Lytvynenko Sergiy , Voitsehovskiy Viktor , Hryhorak Mariia , Vasylenko Igor , Ozerova Olha , Gabrielova Tetiana
Published: April 2023

The article aims to propose new approaches to cargo delivery management in global supply chains in the context of sustainable development. Recently, this issue gaining in importance and needs to be addressed, as international supply chains are becoming more complex, the range of transported goods is increasing, the requirements of the cargo clientele and the reliability of delivery in general are significantly increasing. Within the framework of the study, a critical analysis of scientific sources on cargo delivery technologies, the functioning of transport systems, the formation of global supply chains was carried out. The empirical research is based on the use of methods of systematization, deduction, expert assessments, statistical analysis — in the classification of cargo flows. Methods of statistical observation, correlation and regression analysis, mathematical modeling and optimization were used in the management of airline cargo flows and determining organizationaltechnological principles of interaction between participants in global supply chains. Scientific and practical recommendations for managing the cargo delivery technology in global supply chains are provided, which ensured the interests of all participants and allowed to unify this process in general.
Calculation and experimental study of water distributor of stratification heat accumulator of solar heating system
Authors: Rashidov Yusuf , Aytmuratov Bahadir , Abdullaeva Barno , Aytbaev Kobeysin
Published: April 2023

The calculation method for a water distributor of a constant cross section uniformly perforated along the height for a multilayer stratified thermal storage tank used in solar heating and hot water supply systems was developed.
Investigation of the adsorption properties of the sorbent obtained in the process of modification of clinoptilothite in the purification of natural gas from sulfur compounds
Authors: Sarimsakova Nilufar , Fayzullaev Normurot , Alimboeva Ozoda
Published: April 2023

The study of the possibility of using modified clinoptilolite as an adsorbent and the adsorption properties of zeolite in the purification of natural gas supplied to gas processing plants from sulfur compounds contained in it is an urgent task. In the experimental study, the adsorbent fraction was chosen as 0.5÷1.0 mm, density - 0.8 g/cm3, adsorbent layer height - 600 mm. Optimal conditions are selected in such a way that the pressure in the experimental process is 0.2-5.0 MPa, the amount of mercaptans in the purified natural gas is 50÷400 mg/nm3, the temperature is 20÷25°C, the gas flow rate is 0.2÷250°C. 0.25 m/s. Experiments IR spectroscopic studies were carried out on a NikoletIS-10 IR spectrometer in the frequency range 400-5000cm-1. The phase composition was studied using a 2DPHASER Bruker X-ray analyzer (CuKa - radiation, 2nd, 20-80 degrees). Electron microscopic images were taken under a Hitachi TM-3000 microscope. Elemental analysis was performed at Oxford Science. The intensity and accuracy of desorption of sulfur compounds adsorbed on clinoptilolite at 250°C, the same results were obtained on NaX zeolite at 320°C. The catalytic activity of regeneration of clinoptilolite at lower temperatures than that of NaX zeolite, although small, made it possible to minimize the decomposition of mercaptans. The purpose of this work is to study the adsorption properties of the sorbent obtained in the process of modifying clinoptilotite during the purification of natural gas from sulfur compounds.
Influence of the parameters to transition capacitance at NCDS-PSI heterostructure
Authors: Sapaev I. , Sapaev B. , Abdullaev D. , Abdullayev J. , Umarov A. , Siddikov R. , Mamasoliev A. , Daliev K.
Published: April 2023

It is important to research the dependence of the capacitance and capacitance on the parameters on the photodiodes. In this article, we aim research experimental and theoretical on the nCdSpSi heterostructure. A heavily doped n+CdS layer with a thickness of about 50 Å was created by deposition of a thin layer of indium (In) for 25-30 s on the surface of a CdS film in vacuum with a residual pressure of 10-5Torr at a substrate temperature of 373 K, followed by annealing at 673 K in within 300s. Then, on the surface of this heavily doped n+CdS layer, a current-collecting “P”-shaped ohmic contact with an area of 3 mm2 was obtained also by the vacuum evaporation of In.
Optimization of the method of oxide coating of metallic iron powder particles
Authors: Berdiyev Usan , Demedenko Olga , Ashurov Mirjalol , Hasanov F.F. , Sulaymonov U.B.
Published: April 2023

This article considers the issue of wide implementation in various branches of the national economy caused the intensive growth of electric machines production. Due to the high specific consumption of magnetic materials in the production of electric machines, a very promising direction is the development of waste-free technology of manufacture of magnetic cores and cores by methods of powder metallurgy. The use of powder metallurgy allows reducing losses of electrical steel and eliminating many labor-intensive operations, using powder metallurgy for electrical production, it is possible to obtain sufficiently high efficiency values and reduce hysteresis losses.
Mathematical model of heat and humidified air treatment in the injector camera
Authors: Normuminov J. , Nodirxonova Ch. , Samandarov J.
Published: April 2023

The article describes a mathematical model for the heat-moisture treatment of air in the nozzle chamber. The dynamics of unsteady processes of heat and mass transfer between the working substances in the apparatus and the transfer characteristics, balance equations of exchanging media are considered. A physical and mathematical description of heat and mass transfer processes in a thicker working medium and the relationship between the heat and mass fluxes through a surface unit and the mass-average temperature and potential are presented. The expression and their dependencies are presented for determining the final parameters of air in the irrigation chamber.
Investigation of asymmetry in asynchronous motor used in a borehole pump
Authors: Berdiev U. , Norboev A. , Mamarajabova Z.
Published: April 2023

In this paper, the values of the symmetrical states of asynchronous motors used in borehole pumps are obtained at different time intervals, the results are analyzed, and formulas for changing the symmetrical states over time are developed.
Analysis of the performance and economic parameters of different types of solar panels taking into account degradation processes
Authors: Saitov E. , Kudenov I. , Qodirova F. , Askarov D. , Sultonova M.
Published: April 2023

Analysis of the operational and economic parameters of various types of solar panels, taking into account their degradation. An inspection of literary sources of solar panels was carried out. The types of solar panels, their advantages and disadvantages are described in detail. An analysis of the degradation of solar panels was carried out. The calculation is made and graphs of degradation of solar panels are given. In the feasibility study, capital investment calculations were carried out for the introduction of two network stations with a capacity of 30 kW, with various types of solar panels. Scientific novelty lies in the analysis of the degradation of various types of solar panels.
The new design scheme of drilling rock cutting tools, working in rotation mode pairs
Authors: Toshov B. , Toshov J. , Akhmedova L. , Baratov B.
Published: April 2023

The article describes the dynamics of drill bits, drilling modes, distribution of resistance forces when drilling with bits. The theory of drilling a well of arbitrary shape, possible shapes of contacting figures at the bottom hole and the type of drill bit operating in the rotation pair mode are considered. This type of bit has the properties of a double center of rotation, which results in attrition drilling. At the same time, during drilling, the load on the bit will be located the same throughout the working part, it is also theoretically shown that the specific volumetric and contact work of the cutting parts will be the same, which leads to the same wear of the bit. It also discusses the issues of improving the flushing and blowing of wells when drilling with rotary steam bits.
Evaluation of the possibility of developing and manufacturing integral composite structures for airframe elements
Authors: Pashkov V.S. , Zhuleva A.D. , Tikhtey Yu.N. , Shavelkin D.S. , Popov Yu.I.
Published: April 2023

Nowadays, the degree of structural integrity is as important as the specific load bearing capacity. An integral product can be called a product obtained by combining structural elements of different configurations and functional purposes into a single object that does not contain joints. The concept of “integral”, obviously, is synonymous with the concept of “monolithic”. However, the word “monolithic” is traditionally identified with a massive structure, in which all fragments have the same order of measurement. The very concept of “degree of integration” is very conditional, since now there is no clear methodology for its assessment in quantitative terms. Issues related to the design, manufacture and operation of such products should be addressed in a comprehensive manner based on design solutions, technological capabilities, as well as data obtained as a result of strength calculations. In this paper strength calculations were made for metal and composite panels. Besides, composite panel has integral design. Production specifics of integral composite structures as well as advantages and disadvantages.
Description of the modules of an optimal requirements management system for working with aviation projects
Authors: Gurov Viktor , Deniskina Antonina , Kudryavtseva Irina , Kostyshak Mikhail
Published: April 2023

The article provides information that reveals such concepts as requirement, requirements management. In particular, the necessary specifics for collecting requirements in aviation projects, the scheme for working with requirements, processing requirements, as well as necessary activities such as validation and verification are given. How the above processes interact with each other, as well as their attributes in the requirements management system. Data on the required level of rigor in the collection of requirements and their impact on certification processes are given. The purpose of the article is to show an approach to the development of a more mature requirements management system, to describe the necessary modules in the development of such a system. Show how the system can be divided into subsystems for more detailed study and organization of work with requirements. For each module of subsystems and the system as a whole, select data types and justify them.
Design of z-shaped reinforced panels of composite materials under compression and shear
Authors: Mitrofanov O. , Toropylina E. , Smolyaninov Andrey , Lukmanova Inessa
Published: April 2023

When designing thin-walled aircraft structures, as a rule, the main limitations are associated with ensuring stability. The objects of research in this work are composite z-shaped reinforced panels of the wing box of an aircraft. For the early stages of the design of load-bearing panels, it is necessary to evaluate the weight of the design decisions made, taking into account possible defects. The paper proposes an analytical technique for designing reinforced panels, taking into account the use of the condition of uniform stability and the presence of possible regulated defects in the skin that may occur in further operation. The task of determining the parameters of panels of minimum weight is reduced to minimizing the function of one variable, which is the ratio of the height to the reinforcement step. To take into account the indicated regulated defects, parametric studies were carried out using the finite element method, on the basis of which refinement coefficients were added to the analytical ratios of the stiffness parameters of the reinforced panels. The paper presents the results of studies of orthotropic panels with defects in the form of through holes under loading with compressive and tangential forces. The results are presented in the form of graphs that show possible changes in the critical stresses of thin skins with defects.
Les traces génétiques de la peste noire
Authors: Jordan Bertrand
Published: April 2023

Genetic analysis of human populations before and after the great plague pandemic in the late Middle Ages reveals immune-related loci at which specific alleles have been selected because they conferred (partial) resistance to the pathogen. Some of these alleles are associated with susceptibility to present-day immune diseases, illustrating the complex interplay between genes, environment and the immune system.