bluuebunny/crossref_metadata_2025 huggingface dataset:
The Flood Politicization and Social Media: Ecological Disaster, Satire, and the Contestation of the 2024 Indonesia Presidential Election on Twitter
Authors: Mustofa Mustabsyirotul Ummah , Aulia Muhammad Ridlo , Ramadhani Rahmah , Nurfadillah Karmeta Syahwan
Published: February 2023

As floods are common in Indonesia, social media are full of conversations about this annual disaster. When floods hit Jakarta, Central Java, South Kalimantan and other areas in early 2021, the most-talked issue in the conversations on social media, especially Twitter, was not about how environmental degradation causes the floods but rather about how the heads of the flooded areas are to compete in the upcoming presidential election. Using critical discourse analysis, this study seeks to explore discourses on the flood politicization related to the 2024 presidential election on Twitter. The results show that there are dominant and marginal discourses in the discussion of the flood issue. The dominant discourse is related to the image and ability of the regional heads to overcome the flood which is linked to his capacity as a presidential candidate in the 2024 election. Meanwhile, the marginal discourse is related to policies taken by regional heads in taking preventive actions and post-flood handling. This article shows findings as follows: first, floods as an ecological disaster which causes environmental management are not an important concern of the community as they are regarded as a common issue that happens every year; second, the flood issue was used to criticise the former governor in a satiric way; third, the flood issue was used as a momentum to test the popularity and electability of candidates for the presidential election as a result of the political division after the 2017 Jakarta Election and the 2019 Indonesian Presidential Election. This article argues that the political debate for the 2024 presidential election in Indonesia was more interesting than the awareness of environmental damage.
Will you remember
Authors: Deacon Lauren
Published: February 2023

The official histories have mostly paved over punk in Aotearoa/New Zealand, and in particular, Neil Roberts’s action against the Whanganui Computer Centre in 1982. However, Neil Roberts Day, a community-led day of celebration and remembrance, flies in the face of this generalized forgetting. In this short ‘Riff’, I will begin to explore Neil Roberts Day commemorations through Pierre Nora’s concept of generational consciousness and the lieux des memoires, or sites of memory, and what this might mean for the punk and hardcore communities in Aotearoa/New Zealand.
Writing practices of university students in an online academic English course in Uzbekistan
Authors: Akhmedjanova Diana
Published: February 2023

This reflection focuses on teaching writing online for the first-year students in the Academic English course at the Westminster International University in Tashkent (WIUT), Uzbekistan. Academic English is a core course for all incoming first-year students and aims to develop students’ proficiency in listening, reading, and writing skills. A great emphasis is placed on the development of writing skills, and students are required to write at least four summaries, two essays, and one reflection during the twelve weeks of the first semester. A new challenging component in the autumn 2020 semester was teaching writing online, due to the lockdown caused by the COVID-19 pandemic. The classroom writing processes were examined through the lens of the Self- and Socially-Regulated Multilingual Writing model (Akhmedjanova, 2020), which revealed prevalence of socially-regulated rather than self-regulated writing practices. Also, teachers instructed students to use revision strategies more than planning and formulating writing strategies. A cursory examination of students’ reflections suggested that many students struggled with the environment and time management skills. Future revisions to the Academic English course should include explicit teaching of planning and formulating writing strategies along with planning and time management skills.
Entwining interactive fiction with technical writing to develop structured authoring competencies
Authors: Terry Robert
Published: February 2023

Concerns about teaching structured authoring, which is the use of software in technical writing to allow automatic textual reuse and reassembly, have been woven into the debate about what role technologies should play in preparing technical writing students for ‘real world’ needs since the late 1990s (see Brumberger & Laurer, 2015; Carnegie & Crane, 2019; Kimball, 2015; Rainey et al., 2018). Vee (2017) and others have argued that fundamental aspects of writing software code, many of which parallel structured authoring, are now required literacies. Indeed, as Gentle (2017) demonstrates, the difference between those writing code and those writing structured authoring continues to shrink. Helping to develop technical writers to understand this overlap remains a significant challenge. This article suggests that this challenge might be met by using an open-source interactive fiction authoring platform called Twine, which provides many of the building blocks of structured authoring while teaching fundamental aspects of coding. However, this approach is not without its perils. Through analyzing the findings of a two-year study, this article identifies potential avenues for success as well as potential pitfalls to be mindfully considered.
Screencasting for technical writing students
Authors: Cavanaugh Andrew
Published: February 2023

Significant research has been conducted in the past several decades on best practices in providing feedback to students’ writing. Over the past two decades, feedback methods have evolved as writing classes have transitioned from face-to-face traditional classrooms to online classrooms and as technology has advanced. Written feedback has moved from handwritten notes in the margins of a paper to typed feedback using commenting tools. Audio feedback has gone from the cassette tape to the MP3 file. One of the most recent trends in feedback to students’ writing is in video form using screencasting technology. Video feedback through screencasting is especially beneficial in the technical writing classroom, where students often need to see the problems in their document. Students often benefit from seeing why they need more white space, why their graphics are not clear, why their alignment is off, why their instructions are not precise for their audience, why their numbered steps are not developed correctly, and why a host of other design principles could be improved. Moreover, video feedback through screencasting technology is becoming more popular in the workplace. Exposing students in technical writing classes to screencasting feedback has the potential not only to improve their writing but also to enhance their readiness for the workplace.
An approving gloss to the thesis of the judgement of the Supreme Court of 21st April 2016, ref. III ZS 1/16 regarding legal subjectivity of the Supreme Council of the Chamber of Nurses and Midwives
Authors:   Department of System of Public Administration Faculty of Law, Administration and Economics University of Wrocław, Poland, Charzewski Przemysław
Published: February 2023

On 21 April 2016, The Supreme Court indicated in its judgment that the Supreme Council of the Chamber of Nurses and Midwives has legal subjectivity, which entails that it has both legal personality and judicial capacity. This is also not prevented by its legal status, i.e. being a body of the Supreme Chamber of Nurses and Midwives. It derives its qualities from the role it actually performs, i.e. representing the professional association of nurses and midwives outside. Of course, it follows from both the Act and the literature that the professional association of nurses and midwives has legal personality. However, it follows from the thesis in the judgment that the Supreme Court took into account the fact that without the Supreme Council, the proper performance of tasks by the professional association of nurses and midwives would be in practice impossible in the current legal state (which is justified by the provisions of the Act on the association of nurses and midwives). The author fully endorses this position, which he justifies with the argumentation below.
Odpowiedzialność za szkodę wyrządzoną przez pasera
Authors:   Wydział Prawa i Administracji, Uniwersytet Gdański, Polska, Weiszewska Ewa
Published: February 2023

The article concerns civil liability of the person who intentionally took advantage of the damage caused to another person in the light of the article 422 of the Polish Civil Code. The author considers the above norm on the example of the civil liability of the fence, which in the literature was considered almost a textbook example of conscious use of damage. Therefore, the article presents legal grounds for the liability of the fence. The author analyzes several issues, such as the nature of the fence's liability, definition of conscious action, or joint and several liability of the fence.
Dualizm środków zaskarżenia wadliwych uchwał wspólników w spółce z ograniczoną odpowiedzialnością
Authors:   Wydziału Prawa i Administracji, Uniwersytet Gdański, Polska, Strugalski Tomasz
Published: February 2023

The article deals with the problem of dualism of means of challenging defective shareholder resolutions in a limited liability company. The overall objective of the article is to compare legal effects of the action to declare the invalidity of a resolution with action for its revoking. Therefore, it is needed to look deeper into defectiveness of the legal act regulations. The main conclusion of the legal discussion is that our domestic regulations (Art. 249 and 252 Polish Commercial Companies Code) provide two separate actions which have identical legal effects.
Producing Radio Programs, Mainstreaming Gender Equity: A Case Study of Radio Sonora Semarang
Authors: Agus Triyono  , Arni Ernawati
Published: February 2023

There has been an increase in discussion about gender mainstreaming-related issues on media. Mass media producers’ awareness about gender equity has remained questionable, even regarded as not presenting gender equity as expected. This study attempts to focus on how the production of news programs in Radio Sonora Semarang regarding the issue of gender equality, particularly to what extent the role of women in the process of radio program production. Using a qualitative approach and conducting interviews with Radio Sonora's journalists and the production program team, the findings have revealed that Radio Sonora Semarang highly upholds the values of gender equality in the production process of its programs. There has been mutual respect amongst media workers both men and women in the radio Sonora during program production process. Indeed, women can take roles equally to men without leaving their nature as women.
Feedback‐based self‐learning in large‐scale conversational AI agents
Authors: Ponnusamy Pragaash , Ghias Alireza Roshan , Yi Yi , Yao Benjamin , Guo Chenlei , Sarikaya Ruhi
Published: February 2023

Today, most of the large‐scale conversational AI agents such as Alexa, Siri, or Google Assistant are built using manually annotated data to train the different components of the system including automatic speech recognition (ASR), natural language understanding (NLU), and entity resolution (ER). Typically, the accuracy of the machine learning models in these components are improved by manually transcribing and annotating data. As the scope of these systems increase to cover more scenarios and domains, manual annotation to improve the accuracy of these components becomes prohibitively costly and time consuming. In this paper, we propose a system that leverages customer/system interaction feedback signals to automate learning without any manual annotation. Users of these systems tend to modify a previous query in hopes of fixing an error in the previous turn to get the right results. These reformulations, which are often preceded by defective experiences caused by either errors in ASR, NLU, ER, or the application. In some cases, users may not properly formulate their requests (e.g., providing partial title of a song), but gleaning across a wider pool of users and sessions reveals the underlying recurrent patterns. Our proposed self‐learning system automatically detects the errors, generates reformulations, and deploys fixes to the runtime system to correct different types of errors occurring in different components of the system. In particular, we propose leveraging an absorbing Markov Chain model as a collaborative filtering mechanism in a novel attempt to mine these patterns, and coupling it with a guardrail rewrite selection mechanism that reactively evaluates these fixes using feedback friction data. We show that our approach is highly scalable, and able to learn reformulations that reduce Alexa‐user errors by pooling anonymized data across millions of customers. The proposed self‐learning system achieves a win‐loss ratio of 11.8 and effectively reduces the defect rate by more than 30 percent on utterance level reformulations in our production A/B tests. To the best of our knowledge, this is the first self‐learning large‐scale conversational AI system in production.
A state-dependent multilaminate constitutive model for anisotropic sands
Authors: Bayraktaroglu Hilmi , Hicks Michael A. , Korff Mandy , Galavi Vahid
Published: February 2023

Experimental studies show that initial fabric and its evolution under different stress paths greatly influences soil behaviour. Even though different sample preparation methods create different inherent anisotropies and cause different material responses, the same initial fabric structure under different stress paths also results in different material behaviours. In this paper, a simple state-dependent, bounding surface-based elastoplastic constitutive model, which can simulate the anisotropic nature of sands including the effect of principal stress rotation, is described. The model is developed based on a semi-micromechanical concept within the multilaminate framework and, to include the inherent anisotropy of sand, a deviatoric fabric tensor describing the initial microstructure is introduced. In addition, a fabric evolution rule compatible with anisotropic critical state theory is employed to describe the evolving fabric structure and induced anisotropy towards the critical state. In contrast to the classical strain-driven formulation for fabric evolution, a micro-level evolution rule is proposed. This paper presents concise theoretical aspects of the multilaminate framework and the anisotropic elastoplastic constitutive formulation. The model's capability under drained and undrained monotonic loading conditions at different stress states, relative densities and principal stress orientations is demonstrated by simulating experimental data for Toyoura sand.
ANNA: advanced neural network algorithm for optimisation of structures
Authors: Khodadadi Nima , Talatahari Siamak , Gandomi Amir H.
Published: February 2023

The purpose of this study is to develop an advanced neural network algorithm as a new optimisation for the optimal design of truss structures. The central concept of the algorithm is based on biological nerve structures and artificial neural networks. The performance of the proposed method is explored in engineering design problems. Two efficient methods for improving the standard neural network algorithm are considered here. The first is an enhanced initialisation mechanism based on opposite-based learning. The second relies on using a few tunable parameters to provide proper exploration and exploitation abilities for the algorithm, enabling better solutions to be found while the required structural analyses are reduced. The new algorithm's performance is investigated by using five well-known restricted benchmarks to assess its efficiency in relation to the latest optimisation techniques. The outcome of the examples demonstrates that the upgraded version of the algorithm has increased efficacy and robustness in comparison with the original version of the algorithm and some other methods.
Elaboración de los fundamentos de derecho de una demanda en la jurisdicción ordinaria
Authors:   Universidad Cooperativa de Colombia, Ahumada Escobar Diego Alejandro
Published: February 2023

La presente guía práctica pretende entregar las herramientas conceptuales y pragmáticas para la correcta elaboración del acápite de fundamentos de derecho como requisito de las demandas y acciones legales en la jurisdicción ordinaria, abordando su construcción desde el mero acto de cita normativa, hasta el análisis y la hermenéutica necesarios para argumentar en debida forma la tesis propuesta al juzgador. Los fundamentos de derecho son quizá la parte mas compleja e importante de una demanda después de los hechos, pues es el enlace argumentativo entre la situación fáctica que da origen a la acción judicial (lo que se pretende) y las leyes que respaldan las pretensiones. Sin la correcta integración de conceptos, la demanda pierde su real y único fin, el cual es convencer al juzgador que la tesis del demandante es la correcta y por eso se debe acceder a sus peticiones.
Quantum Efficiency Improvement of InGaN Near Ultraviolet LED Design by Genetic Algorithm
Authors: ALP İrem , ÖNER Bilgehan Barış , EROĞLU Esra , ÇİFTCİ Yasemin
Published: February 2023

A near-ultraviolet (367-nm) InGaN light-emitting diode (LED) with 5.75 nm quantum well depth was designed and both internal/external quantum efficiency (IQE/EQE) values were optimized considering the effects of non-radiative recombination rates and possible fabrica-tion errors. Firstly, the IQE of the design was enhanced by a genetic algorithm code which was developed particularly for this study. Distributed Bragg Reflectors and optional ultra-thin 1nm AlN interlayer were also used to increase overall light extraction efficiency. Then, alloy and doping concentration effects on wavelength-dependent optical and structural parameters were analyzed via the CASTEP software package based on density functional theory to pre-sent a more detailed and realistic optimization. The relatively great values of 42.6% IQE and 90.2% LEE were achieved. The final structure with 1.00 mm × 1.00 mm surface area requires only 200 mW input power to operate at 3.75 V.
Using Chemically Unprocessed Orange Peel to Effectively Remove Hg(II) Ions From Aqueous Solutions: Equivalent, Thermodynamic, And Kinetic Investigations
Authors: ALTUNKAYNAK Yalçın
Published: February 2023

This study looks at the capacity of raw orange peel (ROP) to adsorb Hg2+ ions from aqueous solutions. According to the results obtained, it is aimed at using ROPs more efficiently by recycling them. In this way, the usability of both ROP and other agricultural wastes in adsorption processes can be investigated. The effects of many variables on adsorption efficiency were investigated in the study, including initial metal ion concentration (MIC), contact time (CT), and pH. Under optimal operating conditions for Hg2+ ion adsorption, CT, solution pH, and initial concentration were determined to be 90 minutes, 3.08, and 180 mg/L, respectively. SEM, Fourier transform infrared spectroscopy (FT-IR), energy dispersion spectroscopy, and Brunauer, Emmett, and Teller (BET) analyses were used to examine the surface features of ROP. The isotherm values were found to be appropriate for the Langmuir isotherm model, indicating chemical absorption and likely process irreversibility. At 318, 308, and 298 K, the capacity of adsorption for the Hg2+ ion was calculated to be 66.225, 63.291 and 61.728 mg/g, respectively. The pseudo-second order (PSO), which exhibited the largest regression coefficient and best described the kinetic data for the removal of Hg2+ ions, according to thermodynamic studies, it was seen that the adsorption of Hg2+ ions on ROP is a natural and endothermic process. ROP, which is abundant throughout the world, can be used effectively in its natural state without any modification or chemical treatment, together with Hg2+ adsorption, to remove other heavy metals, dyestuffs, and toxic substances. ROP has been recognized as a potent and promising material for eliminating Hg2+ ions from the aquatic environment due to its characteristics such as high adsorption capability, cheap cost, and ease of availability.
The Effects of the Covid-19 Period on Carbon Footprint in Sakarya University Esentepe Campus
Authors: YİĞİT Mahnaz , ŞENEREN Merve
Published: February 2023

Climate change, one of the biggest threat of global life, is continuously triggered by greenhouse gases released into the atmosphere due to human activities. Carbon dioxide (CO2), one of the most important greenhouse gases, has revealed the concept of carbon footprint, and efforts to take mitigation measures by calculating it have become widespread. With sustainable campus studies, universities, where science and innovations are created, lead other institutions by creating the necessary database for measuring and managing greenhouse gas (GHG) emissions and calculating the corporate carbon footprint. This study calculated and compared the carbon footprints of Sakarya University Esentepe Campus for 2019 and 2020 when distance education was carried out during the Covid-19 pandemic. Greenhouse gas emissions resulting from activities on campus were calculated and converted to a CO2 equivalent. GHG emission factors and the Tier-1 method of the Intergovernmental Panel on Climate Change (IPCC) were used in the calculations. As a result, the carbon footprint was 13273.38 tCO2e in 2019 and 6338.72 tCO2e in 2020. It was determined that the largest share of carbon emissions was due to the use of electrical energy. The results obtained for both years were compared, and a 47.7% reduction in total emissions was evaluated. In the light of current studies on carbon emission reduction, suggestions and measures need to be taken are summarized in this research.
Calorimetric Analysis of Tea and Coffee
Authors: DİNÇ Bircan , ÜSTÜNSOY Recep , ERTAŞ Tahsin
Published: February 2023

Tea and coffee are the most popular beverage and there is a variety of forms in both hot and cold temperatures. Black tea is made from green tea leaves that have been oxidized. During the oxidation process, a certain proportion of polyphenol compounds is lost. More than a thousand chemical components can be found in coffee, making it a complex beverage. One of the significant factors that is stressed equally to the scent and flavor of coffee is the caffeine content. Differential Scanning Calorimetry (DSC) was employed in our study to compare the properties of Turkish coffee, green and black tea, and certain instant coffee brands. The evaluated teas and coffees belong to the most consumed brands in Turkey. Caffeine, which has a melting temperature of 234°C was found in abundance in green teas but not in black teas. Glass transition temperatures (Tg) for tea kinds were found to be approximately 40°C. Polyphenol content melting values are known to be approximately 67-75°C, and the study has verified that teas are high in polyphenol content. The findings of the coffee study showed that the peaks at 170 and 201°C were caused by the melting of several elements, including amino acids, lipids, and sugars, including sucrose, glucose, fructose, arabinose, galactose, maltose, and polysaccharides. Caffeine bonds are broken and degraded at temperatures of 253, 266, 278 °C, resulting in exothermic maxima. The endothermic curves at 39, 41, and 71 °C for pure coffee at three different roast levels are shown. The breakdown of the cellulose components causes the transitions to be visible between 389 and 494°C. The findings of this investigation demonstrated that instant coffees have a higher additive content than Arabica coffee.
Trajectory Tracking via Backstepping Controller with PID or SMC for Mobile Robots
Authors: YİGİT Sinan , SEZGİN Aziz
Published: February 2023

Mobile robot concept is one of the most commonly used nonholonomic system for industrial and academic autonomous applications. There are many types of mobile robot design concepts and control strategies which have been continuously developed by researchers. In this study, two wheeled differential drive mobile robot (DDMR) is used for trajectory tracking study under different conditions. Reference trajectory, dynamic and kinematic motion models of DDMR are defined as mathematical expressions in computer software. For tracking the reference trajectory, error between current pose and reference pose was decreased by sliding mode controller (SMC) and proportional–integral–derivative controller (PID) with kinematic based backstepping controller (KBBC) respectively. A reference path which consists of sinusoidal and linear parts tracked by both controller combinations in first simulation to examine controller tracking performances. In order to examine and compare; responsiveness, stability and robustness of the controllers, an additional mass which affects motion dynamics of DDMR vertically added to the mobile robot body during trajectory tracking application. All results and discussions are comparatively stated at the end of the study with related error figures and evaluations.
Mathematical Modeling of Time Response Analysis of Residual Current Devices with Electronic Switches
Authors: YAĞIMLI Mustafa , YURTCU Ahmet
Published: February 2023

Today, relay contact and electronic residual current relays are used in order to protect human life against electrical shocks and machinery and equipment from malfunctions caused by excessive current. These residual current relays step in at 30 mA level and cut the current from the system. With the developed electronic switch and residual current device hybrid system, the human body residual current value and current cut-off response time were calculated using Monte Carlo Simulation frequency / intensity distributions. In the field of application, data sets were created in this study, which can be realized using physical and ambient data related to the human body resistance value. In this study, the reaction time of the system developed according to the amount of electric current, temperature of the human body, skin and moisture properties, shoes worn, decking, material type characteristics was modeled mathematically by using Monte Carlo simulation.
Close Call: Sagan’s Humpbacks and Nonhuman Politics
Authors: Grebowicz Margret
Published: February 2023

Today’s argument for whale personhood seems to have put the dimension of communication between whales and humans at its periphery. This chapter argues that language is absolutely primary, but not for the reasons we tend to think. Whale sounds are living proof that at the heart of the voice lives everything about language that is not reducible to logos. This means that with both whales and humans we are dealing not with the concept ‘person’, but with actual persons. What does that distinction mean for the place of hearing in political life? When Carl Sagan sent whale sounds into outer space on the Voyager Golden Record it was as part of the United Nations greetings. This was not because he mistook whales for humans, but because the difference was irrelevant from the point of view of his project. Cetacean behaviour and social organisation show that linguistic communication is taking place, but the sphere of human rights still doesn't quite know how to manage this discovery. The language problem haunts the production of the human, endlessly managing its animality. Protection of the human in the sphere of rights is the protection of language – of what we don’t understand, or what has yet to be said. This chapter argues that that yet-to-be-said is coextensive with an animality that announces itself vocally, and that this is what the modern concept of the human actually protects.
Why Record Improvisation?
Authors: Moore Nathan
Published: February 2023

This chapter considers how recording improvised music not only aids in the development of such music but, more to the point, how recordings facilitate the types of listening used by the improvising musician. Recordings constitute an archive through which further abstractions become possible – not as a means of refinement or of reaching some ‘essence’, but for the selection and actualisation of particular potentials. This is compared to the Schmittian katechon as a means of critiquing the latter.
Infinite distohastic square operators in li
Authors:   Karshi State University, Imomov Azam A. , Eshniyazov Abdumalik I. ,   Gulistan State University
Published: February 2023

The article is devoted to bistochastic quadratic operators. The concept of a bistochastic quadratic operator is introduced and the property of such operators is studied. A necessary and sufficient condition for bistochasticity is given. An analogue of Birkhoff s theorem is studied for the class of bistochastic quadratic operators. A sufficient condition for the extremity of bistochastic quadratic operators is obtained, and a necessary condition is also obtained for small dimensions. The concept of bistochastic quadratic operators is generalized, and the concept of a bistochastic operator of arbitrary order is introduced. Contribution of the authors: the authors contributed equally to this article. The authors declare no conflicts of interests.
Determinability of a completely decomposable rank 3 group by its automorphism group
Authors:   Tomsk State University, Timoshenko Egor A. , Tretyakov Ivan V. ,   Tomsk State University
Published: February 2023

In the work of Vildanov, Gaidak, and Timoshenko, all completely decomposable groups of rank 2 were found that are defined by their automorphism group in the class of all completely decomposable groups. In this article, a similar problem is solved for groups of rank 3. It is shown that a completely decomposable group of rank 3 is determined by its automorphism group if and only if it is a direct sum of three almost divisible summands of rank 1, two of which are isomorphic to each other and embed into the third . Contribution of the authors: the authors contributed equally to this article. The authors declare no conflicts of interests.
Prediction of durability of soldered contact joints of chips
Authors:   Tomsk State University, Azin Anton V. , Maritsky Nikolay N. ,   Tomsk State University, Ponomarev Sergey V. ,   Tomsk State University, Rikkonen Sergey V. ,   Tomsk State University
Published: February 2023

The study is aimed at developing a nondestructive testing method for electronic equipment and its components. This method allows one to identify critical design defects of printed circuit boards (PCB) and to predict their service life taking into account the nature of probable operating loads. The study uses an acoustic emission method to identify and localize critical design defects of printed circuit boards. Geometric dimensions of detected critical defects can be determined by X-ray tomography. Based on the results of the study, a method combining acoustic emission and X-ray tomography has been developed for nondestructive testing of printed circuit boards. The stress-strain state of solder joints containing detected defects is analyzed. Durability is predicted using the damage function of the material, experimental fatigue curve with allowance for rheological properties of materials, the temperature effects, and complex stress-strain state. The results of using the developed method for estimating the degree of damage of the electronic board have been verified based on the experimental results of studies carried out in accordance with IPC-9701. The prediction error does not exceed 5%. Contribution of the authors: the authors contributed equally to this article. The authors declare no conflicts of interests.
Differential equations of continuum equilibrium for plane deformation in cartesian axials at biquadratic approximation of closing equations
Authors:   Penza State University of Architecture and Construction, Bakushev Sergey V.
Published: February 2023

The subject under analysis is construction of differential equations of equilibrium in displacements for plane deformation of physically and geometrically nonlinear continuous media when the closing equations are biquadratically approximated in a Cartesian rectangular coordinate system. Proceeding from the assumption that, generally speaking, the diagrams of volume and shear deformation are independent from each other, six main cases of physical dependences are considered, depending on the relative position of the break points of biquadratic diagrams of volume and shear deformation. Construction of physical dependencies is based on the calculation of the secant module of volume and shear deformation. When approximating the graphs of volume and shear deformation diagrams using two segments of parabolas, the secant shear modulus in the first segment is a linear function of the intensity of shear deformations; the secant modulus of volume expansion-contraction is a linear function of the first invariant of the strain tensor. In the second section of the diagrams of both volume and shear deformation, the secant shear modulus is a fractional (rational) function of the intensity of shear deformations; the secant modulus of volume expansion-contraction is a fractional (rational) function of the first invariant of the strain tensor. The obtained differential equations of equilibrium in displacements can be applied in determining the stress-strain state of physically and geometrically nonlinear continuous media under plane deformation the closing equations of physical relations for which are approximated by biquadratic functions.
Minimizing vibration of low-noise fans
Authors:   Tomsk Polytechnic University, Dmitriev Victor S. , Minkov Leonid L. ,   Tomsk State University, Kostyuchenko Tamara G. ,   Children's Technopark "Quantorium", Derdiyashchenko Vladimir V. ,   Scientific Production Center Polus, Panfilov Dmitry S. ,   Scientific Production Center Polus, Ermakov Dmitrij V. ,   Scientific Production Center Polus
Published: February 2023

Reducing the vibration activity of low-noise fans is becoming the most important direction in the creation of their new modifications. It is analytically shown that the efficiency of vibration damping of a mechanical system depends not only on the ratio of natural frequencies, vibration frequencies and damping coefficient, but also on technical solutions for installing dampers, for example, on an elastic or rigid foundation. The article proposes an algorithm for minimizing the vibration activity of a mechanical system which is an axial low-noise fan. To solve the problem of minimizing noise in the operating mode of the fan, an innovative technical solution for the construction of the case is being considered - the walls are made in the form of a "sandwich" consisting of layers of structural materials that provide strength characteristics, as well as noise and vibration protection. Contribution of the authors: the authors contributed equally to this article. The authors declare no conflicts of interests.
Modeling of unsteady filtration in a formation - hydraulic fracture system
Authors:   Bashkir State University, Khabibullin Il’dus L. , Khisamov Artur A. ,   Bashkir State University
Published: February 2023

This paper presents the results of modeling of unsteady fluid filtration in the formation penetrated by a well, which intersects a vertical hydraulic fracture throughout the entire thickness of the formation. The model of a bilinear fluid flow in a formation vertical hydraulic fracture system is considered in the case when the horizontal extent of the formation is considered to be infinite, and the fracture is of a finite length. The bilinearity of the flow means that in the formation - fracture system there are two mutually perpendicular fluid flows: from the formation to the fracture and along the fracture to the well. The analytical solution to a system of equations describing fluid filtration in the formation and fracture is obtained using the Laplace transform method. Analyzing the derived solution, main characteristic features of the filtration in the formation - fracture system are determined.
Inhomogeneous Poiseuille flow
Authors:   Institute of Engineering Science UB RAS, Burmasheva Natal’ya V. ,   Ural Federal University, Dyachkova Anastasiya V. ,   Institute of Engineering Science UB RAS; Ural Federal University, Prosviryakov Evgeniy Yu. ,   Institute of Engineering Science UB RAS; Ural Federal University
Published: February 2023

The paper presents an investigation of the isothermal steady flow of a viscous incompressible fluid in an extended flat layer using hydrodynamic equations. The bottom of the layer under consideration is limited by a stationary solid hydrophilic surface. At the upper boundary of the layer, the pressure field, which is inhomogeneous in both horizontal coordinates, and the velocity field are specified. These boundary conditions allow one to generalize the classical Poiseuille flow. The exact solution, satisfying the set boundary value problem, is described by a series of polynomials of different orders. The highest (fifth) degree of the polynomials corresponds to a homogeneous component of the horizontal velocity. Here, the pressure field depends only on the horizontal coordinates; the dependence is linear. The detailed analysis of the velocity field is carried out. The obtained results confirm that the determined exact solution can describe multiple stratification of the velocity field and the corresponding field of tangent stresses. The analysis of spectral properties of the velocity field is performed for a general case without specifying the values of physical constants that unambiguously identify the studied fluid. Therefore, the presented results are applicable to viscous fluids of various nature.
Sloshing of a liquid fuel in toroidal tanks with account for capillary effect
Authors:   Bauman Moscow State Technical University, Yu Zhao Kai
Published: February 2023

A numerical approach is proposed to solve the linear sloshing problem of an incompressible inviscid liquid with account for surface tension effects, which are predominant in the low-gravity environment. A variational formulation is derived by the linearization of motion equations for the liquid near its initial equilibrium state with consideration of a pressure drop on the free surface and a free-end boundary condition on the contact line. The continuous problem domain is discretized by the finite element method. After discretization, the classical generalized eigenvalue problem is obtained, whose solutions are the natural frequencies and mode shapes. Several examples show the effect of the Bond number and the fluid-filled volume on the liquid behavior in toroidal tanks. A comparison of numerical results with experimental measurements under ground conditions reveals that under microgravity condition, the surface tension force and the boundary condition on the contact line play an important role when determining the natural frequencies and mode shapes of the liquid sloshing. Each fluid-filled volume has its own characteristic Bond number, above which the natural frequencies approximate to the experimental values obtained under ground conditions. The presented results can be used in the coupling dynamic analysis of a spacecraft with propellant tanks. The author is grateful to the supervisor associate professor A.N. Tem-nov for help in formulating the problem and discussion of the results of the work.
Investigation of acoustic characteristics of a single supersonic jet flowing into a flooded space
Authors:   Tomsk State University, Askerov Adil A. , Chervakova Anastasiya V. ,   Tomsk State University, Kostyushin Kirill V. ,   Tomsk State University
Published: February 2023

In this paper, the acoustic characteristics of a single supersonic jet flowing from a nozzle of a rocket engine into a flooded space at different pressure ratios are studied. A system of the Favre-averaged Navier-Stokes equations is used to describe the unsteady flow of a viscous compressible heat-conducting gas in a supersonic Laval nozzle and an outflowing jet. The system is enclosed by the ideal gas law. The implementation of the physical and mathematical model and the numerical studies are carried out using the OpenFOAM Extended open platform based on the modified dbnsTurbFoam solver. A conical nozzle with an opening angle of 45° at the Mach number of 3 at the nozzle exit is considered in this study. Air is used as the working gas. Amplitude-frequency spectra of acoustic radiation at the point located at a distance from the nozzle outlet are obtained at different pressure ratios of the outflowing supersonic jet. Analysis of the amplitude-frequency characteristics of the jet under study shows that the maxima occur mainly at low frequencies. The maximum oscillation amplitude for the considered jet configurations is revealed at a pressure ratio of 1 on a frequency of 787 Hz. The maximum sound pressure level is 149 dB.
To the issue of the modeling of oxide film fracture during aluminum particle ignition
Authors:   Baltic State Technical University «VOENMEH», Babuk Valeriy A. , Budnyi Nikita L. ,   Baltic State Technical University «VOENMEH»
Published: February 2023

Aluminum particles are coated with a protective oxide film. It is known that the oxide film condition controls the aluminum oxidation kinetics. The fracture of the film induces the intensification of oxidation. This feature encourages authors to simulate the film condition after fraction caused by thermomechanical stress. The static strength of the film is a well-studied issue, while the fracture dynamics is still a relevant problem. In this paper, two coefficients describing the film condition after fraction are proposed. The first is based on the ratio of activation rates of critical flaws at the fracture initiation and in a hypothetical case without oxide film relaxation. The second represents the ratio of total times of the activated flaw growth during fracture and under specific reference conditions. Both coefficients are shown to produce adequate results with regard to predicting of more sufficient fractures at higher stress rates. It is assumed that the aluminum particle surface, which is exposed to an oxidizer after film fracture, is proportional to the proposed coefficients. With this assumption, the particle ignition is simulated. It is shown that higher rates of particle heating during ignition induce considerable fractures of the oxide film and the following intense oxidation.
On the shape of the brachistichrone rotating in a vertical plane
Authors:   Moscow Aviation Institute, Gladkov Sergey O. , Bogdanova Sofiya B. ,   Moscow Aviation Institute
Published: February 2023

The paper aims to study the influence of the brachistochrone rotating in its own plane on the gutter shape along which a body moves. The problem is solved with a moving basis, which allows one to account for all forces exerted on the body. Introduction of the moving basis yields a compact system of dynamical equations, whose validity was proven in previous author's papers. In limiting cases, such an approach is used to solve analytically the obtained equations of motion and to determine the shape of curves depending on the parameters in the equations by tabular integration. The latter is illustrated in the figures presented. According to the energy conservation law, which accounts for the rotation of the entire system as a whole, the resulting equations also include the angular frequency of rotation as an additional parameter. In this paper, the case of steady rotation is studied. Such conditions have a significant impact on the brachistochrone. In the limiting case of low rotational speeds, the curve, as it should be, degenerates smoothly into a classical brachistochrone, which is justified by the numerical methods used.
The experimental and analytical study of geometrically nonlinear bending of a cantilever beam under a distributed gravity load
Authors:   Reshetnev Siberian State University of Science and Technology, Zuev Dmitriy M. , Makarov Dmitriy D. ,   Reshetnev Siberian State University of Science and Technology, Okhotkin Kirill G. ,   Reshetnev Siberian State University of Science and Technology; JSC Information Satellite Systems Reshetnev
Published: February 2023

This paper describes an approximate analytical solution for the geometrically nonlinear bending of a thin elastic cantilever beam under a uniformly distributed gravity load. The solution is based on the linearized Euler-Bernoulli equation of mechanics of materials. Traditionally, such a linear approach is used for small (geometrically linear) deflections. The authors have modified the original equation with an arc-length preservation condition. The modified solution allows one to obtain bending shapes, deflection, and axial displacement in the range of loads corresponding to geometrically nonlinear bending of a beam (large deflections). An experimental study is conducted to verify the proposed solution. A thin steel band bent by gravity is used as a sample. Changes in the length of the bent sample part allow one to obtain various dimensionless load parameters. The deflections and axial displacements averaged on experimental statistics are determined. Bending shapes are obtained by the least square method of 5th order. Experimental and theoretical data are shown to be in good agreement. This fact confirms that the approximate analytical solution can be applied to solve large deflection problems in a wider range of loads than normally considered in the original linear theory.
A Framework for Assessing Going Concern and Prudence Through the Prism of Risks in the Organization’s Internal and External Control
Authors:   Novokurs Center for Continuing Professional Education LLC, Ali-Askiari Sarvaz A.
Published: February 2023

The research novelty consists in proposing a new approach to assessing the risks of an organization’s activities in terms of the going concern principle and the requirement of prudence. The aim of the article is to propose a mechanism for assessing the components of the internal control system through a matrix of the magnitude of risks. The study allows assessing the going concern and due diligence requirements in the organization’s activities, and to timely identify their impact on the company’s development strategy. The study employed general scientific methods, methods of structural and logical analysis, an expert method for assessing risks. The theoretical and methodological foundations of the study were the works of modern scientists, international and current regulatory documents. The values of the estimated probability of risks to occur, the scale of influence on the financial result and the timing of their manifestation are presented, which allows using them at enterprises different in activities and form of ownership. The results of the study can be used by commercial corporate organizations, non-profit institutions, and public sector organizations in assessing the going concern risks and prudence for a rational approach to assessing income and assets.
On the Background and Basis for Innovative Entrepreneurship Research
Authors:   Kazan National Research Technical University named after A.N. Tupolev, Yudina Svetlana V. , Mingazova Olesya N. ,   Kazan National Research Technical University named after A.N. Tupolev
Published: February 2023

The authors of the article touch upon the question whether entrepreneurial activity is changing in the direction of innovation, or the innovative type of entrepreneurship is becoming more noticeable and significant in the system of economic relations. For that, they attempted to classify entrepreneurial activity by the nature of its origin: as a source of income, as a new market opportunity, as an innovation. The activity of using the terms “innovative entrepreneurship” and “technological entrepreneurship” in scientific publications is analyzed. Some reasons for the low innovative activity of Russian small and medium-sized enterprises in the South-Eastern economic zone of the Republic of Tatarstan are investigated. Based on the study, the authors draw a conclusion that large business can be a significant factor in the development of a small innovative entrepreneurship, and the nature of its influence requires a deep complex study.