bluuebunny/crossref_metadata_2025 huggingface dataset:
Quaternary CsPbX3 (X = Cl1−xBrx, Br1−xIx) alloy microplates synthesized by single-step chemical vapor deposition and their two-photon absorption (TPA) properties
Authors: Hossain Mohammad Kamal , Qarony Wayesh , Wang Ying , Kwok Cheuk Kai Gary , Egbo Kingsley O. , Tsang Yuen Hong , Ho Johnny C. , Yu Kin Man
Published: January 2024

Because of their well-defined light–matter interaction volume, high-quality single-crystalline nature, and precise bandgap tunability, all-inorganic cesium lead halide (CsPbX3 (X = Cl, Br, I)) perovskite (IHP) microplates are of fundamental and technological interest today.
A high-performance magnetoelectric non-volatile light-emitting memory device
Authors: Wu Jia-Wei , Chao Yu-Chieh , Lin Jia-Yu , Ho Chia-Chun , Lai Meng-Ching , Hsu Fang-Chi , Chen Yang-Fang
Published: January 2024

A novel magnetoelectric light-emitting memory (LEM) device that can control the output light intensity and electrical signal based on the input magnetic and electric field strengths has been proposed and demonstrated.
A deep learning fusion model for accurate classification of brain tumours in Magnetic Resonance images
Authors: Zebari Nechirvan Asaad , Mohammed Chira Nadheef , Zebari Dilovan Asaad , Mohammed Mazin Abed , Zeebaree Diyar Qader , Marhoon Haydar Abdulameer , Abdulkareem Karrar Hameed , Kadry Seifedine , Viriyasitavat Wattana , Nedoma Jan , Martinek Radek
Published: January 2024

Detecting brain tumours is complex due to the natural variation in their location, shape, and intensity in images. While having accurate detection and segmentation of brain tumours would be beneficial, current methods still need to solve this problem despite the numerous available approaches. Precise analysis of Magnetic Resonance Imaging (MRI) is crucial for detecting, segmenting, and classifying brain tumours in medical diagnostics. Magnetic Resonance Imaging is a vital component in medical diagnosis, and it requires precise, efficient, careful, efficient, and reliable image analysis techniques. The authors developed a Deep Learning (DL) fusion model to classify brain tumours reliably. Deep Learning models require large amounts of training data to achieve good results, so the researchers utilised data augmentation techniques to increase the dataset size for training models. VGG16, ResNet50, and convolutional deep belief networks networks extracted deep features from MRI images. Softmax was used as the classifier, and the training set was supplemented with intentionally created MRI images of brain tumours in addition to the genuine ones. The features of two DL models were combined in the proposed model to generate a fusion model, which significantly increased classification accuracy. An openly accessible dataset from the internet was used to test the model's performance, and the experimental results showed that the proposed fusion model achieved a classification accuracy of 98.98%. Finally, the results were compared with existing methods, and the proposed model outperformed them significantly.
Disturbance observer‐based model predictive control of a coaxial octorotor with variable centre of gravity
Authors: Derakhshan Reza Ebrahimpour , Danesh Mohammad , Moosavi Hassan
Published: January 2024

This paper presents a model predictive control (MPC) approach based on the extended disturbance observer (EDOB) for trajectory tracking of a coaxial octorotor unmanned aerial vehicle (UAV). First, the system dynamic model is derived using Newton–Euler relations in the presence of time‐varying centre of gravity (COG); then, a two‐loop cascade structure is presented to perform the trajectory tracking task. Both loops are controlled using MPC with feedforward compensation based on the EDOB to improve disturbance rejection abilities. When the mass changes, the moment of inertia and COG are affected. The EDOB simultaneously estimates the effects of time‐varying mass, external disturbances, and parametric uncertainties in six degrees of freedom. After obtaining virtual control inputs using designed controllers, constrained control allocation is used to obtain rotors speed in a valid range. The proposed control scheme is evaluated using simulation. The simulation results show the ability of the developed control strategy in accurate trajectory tracking and stable flight in different conditions and being robust to uncertainty and disturbance.
Ultra‐high frequency sensors positioning on the power transformer to mitigate the negative effects on the partial discharge localization accuracy
Authors: Jangjoo Mohammad Amin , Allahbakhshi Mehdi , Mirzaei Hassan Reza
Published: January 2024

This paper proposes a new method for improving the partial discharge (PD) localization accuracy by detecting the best places of ultra‐high frequency (UHF) sensors on the power transformer tank. In this way, firstly, the critical sites inside the power transformer that can produce PD are determined. Then the sensors’ positioning is done in such a way that if the PD happens at each point of these critical sites, the distance between the estimated PD location obtained by solving the time difference of arrival (TDOA) equations and the actual PD location is laid in an acceptable range. For this purpose, the TDOA equations are linearized around the critical PD coordinates as a matrix form A.X = B. The configuration of the sensor positions that minimizes the condition number of the matrix A is the best configuration. To evaluate the effectiveness of the proposed method, several simulations and evaluations are performed on a power transformer in the CST software. The obtained results and comparing them with the previous method and also conventional arbitrary sensors positioning confirm the effectiveness of this method.
Research of simulation and experiment on arc characteristics of gas mechanical switch
Authors: Jiang Cheng , Qu Lu , Yu Zhangqing , Gan Zhizheng , yan Xin , Zeng Rong , Huang Yulong , Li Shaofu
Published: January 2024

An arc is the high‐temperature discharge plasma produced in the opening process of mechanical switches, which directly affects the breaking capability of a hybrid DC circuit breaker. According to the physical mechanism of an electric arc, the construction of an arc model for simulation analysis is an important technical means in the electrical field. In this study, based on the theory of magneto hydrodynamics (MHD), a gas mechanical switch model of a natural commutation DC circuit breaker with a compound gap is established. The arc motion process under different conditions is simulated and calculated. The influence of different initial pressures, different opening speeds, and different striking currents on the arc voltage characteristics is analysed. The results show that the larger the gas pressure, the smaller the arc volume and the higher the arc voltage. The faster the opening speed, the longer the arc and the higher the arc voltage; with the increase of the current, the arc voltage increases rapidly at a low current, while the arc voltage increases slowly at a high current.
Temperature drift suppression for micro‐electro‐mechanical system gyroscope based on vibrational‐displacement control with harmonic amplitude ratio
Authors: Bu Feng , Feng Rui , Guo Shuwen , Zhou Ming , Wang Yiwang , Wang Feng
Published: January 2024

Micro‐electro‐mechanical system gyroscope detection output is susceptible to drift due to ambient temperature variations. Furthermore, the drive‐mode vibration amplitude is affected by the signal pickup circuit and structural parameters, which significantly influence the temperature drift of the bias and scale factor (SF). This study proposes a vibration amplitude control method based on harmonic amplitude sideband‐ratio (SBR), namely SBR‐AGC, which characterizes the vibration amplitude using the harmonic amplitude ratio of the vibrational electrical signal. The constancy of vibration amplitude is maintained via closed‐loop control to suppress bias and SF temperature drift. The experimental results on cobweb‐like disk resonator gyroscope reveal that the temperature coefficient of bias in the SBR‐AGC mode lies within −20 to 60°C and decreases by 36%, and the temperature coefficient of the SF lies within −10 to 50°C and decreases by 49.7%. Therefore, the environmental adaptability of the gyroscope is effectively improved.
A family of Z‐source‐based half‐bridge inverters: Topology derivation
Authors: Aalami Mohmmadamin , Babaei Ebrahim , Zadeh Saied Ghassem
Published: January 2024

Z‐source‐based half‐bridge inverters are a type of Z‐source inverters whose outer stage is a half‐bridge inverter. This paper presents a generalized structure from which 16 configurations can be derived. Once this topology has been introduced, one of the derived topologies, out of 16, is analyzed in detail based on the appropriate control method. According to these analysis results, this topology's boost‐factor and some equations to design passive and active devices are obtained. Next, it will be tried to derive the equations for each topology based on the obtained results for one of the configurations. In the next step, the topology that has been analyzed is considered to evaluate the efficiency of this topology using the power losses study. Hereafter, the generalized configuration's merits and downsides are studied by comparing it with other similar topologies. Finally, the experiment in the final section checks the operation and validity of the obtained results.
Dual‐input single‐output high step‐up DC–DC converter for renewable energy applications
Authors: Mohammadi Farid , Khorsandi Amir
Published: January 2024

This paper introduces a dual‐input single‐output (DISO) non‐isolated DC–DC converter with the capability to accommodate multiple input ports. It supports both bidirectional and unidirectional power flows. The proposed converter employs the switched‐capacitors (SC) technique, resulting in a high‐ voltage transfer gain. Although the use of the SC technique leads to discontinuous input current, this issue has been addressed by incorporating an inductor at the input side. The DISO high‐voltage gain converter offers flexible control options, reduces current and voltage stress on semiconductors, and imposes no duty cycle limitations due to the proposed switching methods. Furthermore, when Port 2 fails, the proposed converter can transfer energy to the load by sources in Port 1 without interruption. The steady‐state model and small‐signal analysis (SSA) of the proposed converter are examined at continuous conduction mode (CCM). To evaluate accurately, the proposed converter is compared with the recently presented converters based on important characteristics. Additionally, a comprehensive power loss analysis is performed. Following the design specifications, an evaluation and testing of a prototype are conducted to verify the feasibility and performance of the converter.
Machine learning autoencoder‐based parameters prediction for solar power generation systems in smart grid
Authors: Zafar Ahsan , Che Yanbo , Faheem Muhammad , Abubakar Muhammad , Ali Shujaat , Bhutta Muhammad Shoaib
Published: January 2024

During the fourth energy revolution, artificial intelligence implementation is necessary in all fields of technology to meet the increasing energy demands and address the diminishing fossil fuel reserves, necessitating the shift towards smart grids. The authors focus on predicting parameters accurately to minimise loss and improve power generation capacity in smart grids, given that accurate parameter prediction is essential for traditional power grid stations converting to smart grids. The authors employ an artificial intelligence‐based machine learning model, namely the long short‐term memory, to predict parameters of a solar power plant. After analysing the results obtained from the long short‐term memory model in graphical visualisation, the model is further improved using two different techniques namely, a convolutional neural network‐long short‐term memory and the authors proposed an autoencoder long short‐term memory. Comparing the results of these models, the study finds that autoencoder long short‐term memory outperforms the convolutional neural network‐long short‐term memory as well as simple long short‐term memory. Thus, the use of artificial intelligence in this study substantially enhances the precision of parameter prediction by augmenting the performance of rudimentary machine learning models, thereby facilitating the attainment of a resilient and resourceful power system that overcomes power losses and ameliorates production capacity in the context of Smart Grids.
An operation site security detection method based on point cloud data and improved YOLO algorithm under the architecture of the power internet of things
Authors: Yang Shibo , Wang Yu , Guo Shuai , Feng Shijie
Published: January 2024

An operation site safety detection method based on point cloud data and improved YOLO algorithm under the power Internet of Things architecture is proposed to address the complex environment of power construction sites and the poor effectiveness of most existing object detection methods. Firstly, an operation site safety supervision system was designed based on the power Internet of Things architecture, and efficient image processing was achieved through cloud edge collaboration. Then, point cloud data and on‐site monitoring information are used on the edge side to extract the accessible area, ensuring that the target is located in a safe area. Finally, the YOLO algorithm is improved in the cloud by using clustering algorithms, network structure optimization, and other methods, and used to detect targets and determine whether their behaviour meets the safety requirements of the operation site. Based on the PyTorch deep learning framework, the proposed method was experimentally demonstrated, and the results showed that its average detection accuracy and time were 94.53% and 68 ms, respectively, providing technical support for achieving remote monitoring of power operation sites.
Information system as used to monitor sowing, care and harvesting on agricultural lands
Authors: Logachev Maxim , Simonov Vladimir
Published: January 2024

Active digital transformation of Russian agriculture, especially of precision agriculture, accounts for the relevance of the present research. The developed reference information systems and software products that automate processes in this area are independent and most often do not cover the full cycle of obtaining agricultural products. Integrated use of methods for designing and developing a software product allowed creating an information system used to monitor agricultural plants growth. The present research describes the functionality of the developed system, and lists user categories and user interface prototypes.
Features of development of an agricultural warehouse digital twin
Authors: Krasnikova Irina Nikolaevna , Simonov Vladimir Lvovich , Petelin Aleksander Evgenievich
Published: January 2024

The article presents the main results of the development of simulation model of agricultural warehouse. Such a model is a digital twin of the real object that reflects all qualitative and quantitative characteristics of objects and included processes. The creation of such digital twin is necessary to assess the effectiveness of the organization of storage, packing, loading and unloading of agricultural products. The relevance of the research lies in the specificity of realization of the above processes due to their intensity depending on the season, microclimatic conditions of the premises, fragility, and short life of products. As a result of using the methods of structural analysis, simulation modeling and graphical method, all key objects and processes of the subject area are established and characterized, behavioral models and three-dimensional visualization of the simulation model are developed.
The first data on the concentration and emission of methane and carbon dioxide in the underground sources of the Peshernaya beam of Lake Baskunchak
Authors: Garkusha Dmitry N. , Fedorov Yury A. , Kovalev Evgeny A. , Andreev Yuri A. , Tambieva Natalia S.
Published: January 2024

For the first time, full-scale measurements of methane and carbon dioxide emissions by the chamber method were carried out in summer for groundwater sources discharged in the valley of the creek of the Peshernaya beam, located in the north-west of Lake Baskunchak. The values of pH, temperature, concentration of basic ions and methane were determined in the water of the sources. A detailed description of the identified groundwater sources was carried out, their primary morphometric and morphological characteristics were measured, as well as the flow rate. It has been established that more than ten ascending karst groundwater sources are discharged in the Peshernaya gully, five of which were active during the research period and were mainly confined to the left branch of the gully. The active sources of the left side of the beam are characterized by a small flow rate and are sodium chloride brines with a mineralization of 93.9–107.1 g/l. The concentration of methane in the water of active sources varied between 26.3–38.4 µl/l and was on average more than 2 times higher than in the waters of the stream fed by them and an inactive source. The specific flow of methane from the water surface of active sources varied in the range of 0.6–1.5 mg/(m2·hour), which is 2 orders of magnitude lower than the specific flow of CO2, which is 46.4–106.1 mg/(m2·hour).
Economic analysis of permanent plants by categories of farms of the Kyrgyz Republic
Authors: Belek uulu Esenbek , Shaiyldaeva Asel Kokoevna , Chortombaev Ulan Tyrgootovich , Shakirova Klara Kapanovna , Nazarbekova Emilia Umbetovna , Kasymova Nazira Omurkulovna
Published: January 2024

The article gives an assessment of the current state of agricultural crops and perennial plantations in terms of qualitative and quantitative indicators, as well as a correct statistical analysis by category of farms in the Kyrgyz Republic. The purpose of the article is to study the analytical support of the process of managing perennial plantations, in particular, to identify the methodological features of the analysis of perennial plantations. Development of a system of analytical indicators to assess the process of reproduction in the field of perennial plantations, as well as statistical analysis of arable land of agricultural crops and perennial plantations by category of farms of the Kyrgyz Republic. In the future, the horticulture sector, especially fruit and berry crops in all regions, is more favorable for the development of the economy of the republic. The efficiency of the use of agricultural land and the development of perennial plantations, fruit and berry crops are considered. This suggests that the bulk of agricultural land is privately owned, and peasant (farmer) households aim to use their private land for perennial plantings to produce the most cost-effective and efficient crops.
Development of service infrastructure for private motor boats in the northern regions
Authors: Shvetsova Svetlana
Published: January 2024

This article examines the current trends in the development of infrastructure for the maintenance and repair of private motor boats in the northern regions (on the example of the Republic of Sakha (Yakutia)). A survey of motor boat owners in three different groups was conducted. The survey data provide data on the most relevant areas of infrastructure development for the maintenance and repair of private motor boats in the region. Results of the study of current trends in the development of infrastructure for maintenance and Repair of private motor boats can be used for the development of programs for the development of water transport infrastructure, by manufacturers of motor boats, as well as in conducting new research in this area.
Transition from traditional cars to electric ones in Arctic regions
Authors: Shvetsov Alexey
Published: January 2024

The study analyses the prospects for the transition from traditional vehicles running on gasoline and diesel fuel to more environmentally friendly types of vehicles (electric) in the northern and arctic northern and arctic regions. Using the example of two types of passenger cars (traditional and electric), the dynamics of changes in the readiness of residents of the northern and Arctic regions to choose an electric car for movement was analyzed. Measurements were taken before and after trial use. The results of the study on the prospects for the transition from traditional vehicles running on gasoline and diesel fuel to more environmentally friendly types of vehicles (electric) in the northern and arctic, northern and arctic regions may be of interest to companies producing electric vehicles and infrastructure designers for electric vehicles.
Dielectric separation
Authors: Mamadzhanov Bahodirjon , Shukuraliev Abrorbek , Mannobboev Shukhratbek , Turaev Shoyadbek , Patidinov Aslidin , Mavlyanova Shakhnoza
Published: January 2024

This article describes the dielectric sorting methods, the pros and cons of existing dielectric sorting machines. At the cotton ginning plants of the Republic of Uzbekistan, the widely introduced KSM-1-15 sizing and sorting machine is used to sort bare cotton seeds. Its disadvantage is that during prolonged operation, the holes of the perforated vibrating gratings become clogged with seeds, and the calibration process deteriorates.With this sorting, both small seeds with a very low and high specific gravity, and a part of seeds with a high weight of 1000 seeds, but a relatively low specific gravity, go into marriage. Some of the seeds are damaged. The sowing fraction of seeds with the same size retains a pronounced heterogeneity in terms of nutrient supply and maturity Therefore, methods and devices are needed that are capable of separating seeds according to the combination of physic-mechanical and chemical-biological properties of seeds. These requirements are met by the dielectric method of sorting seeds in an electric field.
Improving the efficiency of diesel filters to reduce the adverse impact of fuel on the environment
Authors: Dadashov Gurban H. , Babin Vladimir V. , Alekseev Ivan E. , Serebrennikov Yuri E. , Romanenko Maxim Yu.
Published: January 2024

This paper presents the quality requirements for the treatment of diesel fuel to reduce environmental pollution. The total operating costs of the conventional diesel treatment system are considered. The results of the dependence of the components of the costs and the total costs of cleaning diesel fuel on the quality of preliminary cleaning are summarized. A plan has been developed to minimize the cost of pre-treatment of diesel fuel.
Safety data sheets for chemical laboratories associated with environmental engineering
Authors: Ibragimov Irek
Published: January 2024

Safety data sheets for chemical laboratories associated with environmental engineering are an essential document for conducting various experiments in laboratories. This document contains a list of toxic substances, a first aid kit, instructions for the proper disposal of waste, and other things that will definitely increase safety in the proper operation of laboratories. Such a passport has a reference character. Its purpose is to provide consumers, production and enterprise personnel, emergency services personnel with sufficient information about the safe handling of specific products and about the actions to be taken in case of danger to protect people and the environment. The structure of the passport and its contents are precisely defined by international rules. A chemical laboratory is a room specially adapted for technical and research experiments.
Development of human capital through assessing the level of competencies of higher education programs in modern economic conditions
Authors: Kharina Olga , Zhdanov Eduard
Published: January 2024

In the modern world, economic conditions are rapidly changing. It forces society to respond as quickly as possible. The key to the prosperity of states and the people living in them is the creation and development of an economy based on innovation. New technologies appear due to the accumulated knowledge, skills, abilities - the competencies of the people who create them - human capital. Management of human capital development is directly related to training and education. The article examines how the programs of higher education influence the formation of students’ competencies, how the level of mastery of competencies is assessed. The research proposes mechanics for assessing the level of mastery of competencies. It describes their relationship with assessing the level of qualification of a subject of economic activity.
Investigation of the conditions of movement of magnetic transport devices on ferromagnetic surfaces of various orientations
Authors: Koryagin Sergey , Sharkov Oleg , Velikanov Nikolay
Published: January 2024

Every year, more and more enterprises are automated, robotic facilities are produced in tens of thousands. A special niche is occupied by transport devices moving along curved surfaces. Sheathing of ships’ hulls, tanks, towers, gas storage facilities, and similar metal structures is convenient to maintain during operation and repair with magnetic transport devices. The computational schemes and mathematical models of transport devices of magnetic type with wheel propulsors on ferromagnetic surfaces are presented in this paper. Geometric and force parameters affecting movements on horizontal, inclined, and vertical surfaces were investigated. The gravity of the transport device, the reaction of the processing equipment, the traction between the drive wheels of the bogie and the ferromagnetic surface, the normal reaction of the ferromagnetic surface to the drive wheels, the attraction developed by the electromagnet were taken into account. The results obtained will contribute to the introduction of mathematical modeling methods into the practice of designing magnetic transport devices moving on ferromagnetic surfaces.
Development of construction of a screw conveyer that transports and cleans cotton, justification of screw parameters
Authors: Yuldashev Kozimjon , Djuraev Anvar , Teshaboev Oybek
Published: January 2024

In the article, a scheme of a new design of a zig zag-shaped screw conveyor screw for transporting and cleaning cotton was developed, as a result of the analysis of the movement of a piece of cotton on a mesh surface along the screw surface, a calculation scheme representing the force vectors of the cotton piece under the influence of the conveyor screw was built, and the change of the angle of elevation of the conveyor screw to the cotton piece was developed. (lint) mass and the diameter of the screw, the change of the angle of elevation of the conveyor screw to the change of the angular speed of the screw and the change of the angle of elevation of the conveyor screw to the coefficient of friction of the cotton piece with the mesh surface and the change of the radius of the screw were built. Based on the analysis of the graphs of the parameters, the values of the screw pitch angle that ensure sufficient cleaning efficiency and high productivity have been determined.
Thе imрасt of the disс roller's diаmeter on the сombined mасhine's рerformаnсe during the sequentiаl рroсessing of freshlу рlаntеd sоil
Authors: Muqimova Dаvlаtkhоn K. , Zingirоv Sаidоlim J. , Ахmаtоhunоv Bахtiоr M. , Zоkirоv Dоstоnbеk Z. , Mеlikuziеv Аbdulаziz R. , Tursunbоеv Lосhinbеk Е.
Published: January 2024

When рlаnting fields free of wheаt or soуbeаns in the рubliс сonditions, the toр lауer of soil сontаining рlаnt residues аnd weeds is turned over аnd thrown into the bottom lауer, сreаting numerous gарs аnd irregulаrities in the рlаnted field. Thus, when рreраring freshlу рloughed fields for рlаnting, the soil раrtiсles left behind bу the рloughed bodies ought to be сomрасted, сomрасted, аnd leveled. Bаsed on the аforementioned, the Indiаn Institutes of Аgriсulture аnd Аgriсulturаl Teсhnologу аnd the Indiаn Institute of Meсhаniсаl Engineering hаve develoрed аn industriаl version of the сombined mасhinerу used in the рreраrаtion of new аrаble lаnd for рlаnting. The аrtiсle desсribes the imрасt of the diаmeter of these сombined mасhine disseсtion rollers on the deviсe's рerformаnсe аnd indiсаtes thаt the diаmeter of the сombined mасhine rollers should be between 415 аnd 490 mm to ensure quаlitу рroсessing аt the neсessаrу level with low energу сonsumрtion on аvаilаble lаnd.
Environmental safety problems of swarm use of UAVs in precision agriculture
Authors: Yablokova Alena , Kovalev Dmitry , Kovalev Igor , Podoplelova Valeria , Astanakulov Komil
Published: January 2024

Digital technologies are an integral part of the functioning of many sectors of the state, which applies, in particular, to the agricultural sector, which plays a significant role in shaping the state’s economy, ensuring food independence and export potential. One of the promising areas of digital transformation is the swarm use of unmanned aerial vehicles in precision agriculture, the use of which significantly increases productivity while reducing production costs. Analysis of the transport and technological cycles of UAVs allows us to identify a number of existing problems in the swarm use of UAVs that are associated with anthropogenic impact. The article examines the potential impact of unmanned aerial vehicles on the environment, analyzing such aspects as noise and vibration emissions, air and soil pollution, electromagnetic radiation, and the impact on biodiversity and ecosystems in general. The study is aimed at identifying key environmental problems, identifying ways to minimize and solve them. The authors offer recommendations for ensuring environmental safety and sustainable development of precision agriculture with the swarm use of unmanned systems.
Detection of internal security incidents in cyberphysical systems
Authors: Iskhakova Anastasia
Published: January 2024

This paper addresses the issue of internal security breaches in cyber-physical systems framing it as an anomaly detection problem within the framework of machine learning models. The use of powerful mathematical apparatus embedded in the structure of machine learning models, including models based on artificial neural networks, allows building an autonomous system for detecting internal security breaches with minimal reliance on expert assessments. The determination of user abnormality is made on the basis of average data on log entries of actions in the system identified as abnormal, as well as on statistical data on the number of such entries for each user. The results presented here demonstrate the successful application of these models to the task of identifying insider threats to system access subjects.
Study of fuel injection and atomization processes of a diesel engine running on petroleum fuel and biofuel
Authors: Maldonado Pablo Ramon Vallejo , Devyanin Sergey , Markov Vladimir , Neverov Vsevolod , Safin Airat , Yakushev Adel
Published: January 2024

The relevance of the article is due to the need to replace petroleum diesel fuel with fuels obtained from alternative raw materials. Rapeseed oil is considered as an alternative motor fuel. The properties of petroleum diesel fuel and rapeseed oil are analyzed. The influence of these properties of fuels on the characteristics of their injection and spraying is investigated. The deterioration of the quality of the injection and spraying processes was noted when the engine was switched from petroleum diesel fuel to rapeseed oil. When replacing diesel fuel with rapeseed oil, a slight increase in the maximum injection pressure and the duration of fuel supply was noted. Other parameters of fuel injection and atomization processes practically did not change. To achieve the required performance indicators of the diesel engine, it is necessary to implement measures that improve the quality of the workflow. These measures include the regulation of the fuel injection advance angle, optimization of the geometry of the flow part of the nozzle sprayer, two-phase fuel supply. It is advisable to switch from rapeseed oil to mixed biofuels and optimize their composition.
Optimization of HIsmelt reactor parameters for efficient combustion and heat transfer by numerical simulation
Authors: Chen Wanxin , Wang Zhenyang , Si Ruishuai , Li Ruiyu , Yang Lingxuan , Zhang Jianliang , Zhao Baojun
Published: January 2024

HIsmelt, as one of the non-blast furnace ironmaking processes, is rapidly becoming a focus of attention in the steel industry due to its outstanding advantages in terms of low requirements for raw materials and short and environmentally friendly process. In HIsmelt, a reasonable inner shape of a smelting reduction vessel has an important influence on combustion and heat transfer through changing flow field. Therefore, in this study, the effects of HIsmelt reactor parameters including oxygen-lance insert depth, and smelting reduction vessel body height and throat angle on combustion and heat transfer are investigated through the numerical simulation of the flow field, temperature field, and CO2 concentration field inside smelting reduction vessel. The results show that the heat transfer effect is further improved when increasing the oxygen-lance insert depth because the U-shaped vortex affects a wider area. In addition, as the smelting reduction vessel body height increases and the throat angle decreases, the U-shaped vortex gradually moves away from the melt pool and increases the scouring of the sidewalls. The increased temperature difference and low CO2 concentration indicate that this change reduces the combustion and heat transfer efficiency.
Microstructure and mechanical properties of double side friction stir welded AA 7075 aluminum alloy
Authors: Vernapu Kiran Kumar , Kanchu Venkata Durga Rajesh , Sajja Rama Koteswara Rao , Thadivaka Ramakrishna , Tadivaka Srinivasa Rao
Published: January 2024

Friction stir welding of aluminum alloys is, nowadays, widely used in several industries and the welded joints are expected to exhibit adequate weld characteristics. In fact, normal single side friction stir welds, particularly thick section joints, are prone to reductions in weld properties due to higher heat inputs. Double side friction stir welding (DS FSW) is considered to be one of the possible solutions to address the problem of weld property reductions. Hence, the present work aims at investigating the possibility of improving the joint properties of welds by welding from both sides. Double side friction stir welds were made using 10 mm thick AA7075 plates and the welds were investigated for mechanical properties using hardness, tensile, impact and bend tests. Microstructure, precipitate morphology and fracture surface of the samples were also studied by optical (OM), transmission electron (TEM) and scanning electron microscopies (SEM), respectively. The results showed that the weld nugget exhibits fine equiaxed grains and severe dissolution of strengthening precipitates. In addition, the hardness of the double side welds improved by about 20 HV compared with that of single side welds due to increased survival rate of strengthening precipitates in the WN and reduced PFZ's width in the HAZ. The results of tensile and impact tests showed that in DS FSW samples, the yield strength increased by about 30 MPa and impact toughness increased by 4.83 J compared with single side welds. By and large, it was observed that the better microstructural and mechanical properties can be achieved by double side friction stir welding.
Hydrothermal synthesis of zirconia doped with naturally mixed rare earths oxides and their electrochemical properties for possible applications in solid oxide fuel cells
Authors: Ghiță Andreea-Nicoleta , Slobozeanu Anca Elena , Licu Lidia , Ciobota Cristina Florentina , Sobetkii Arcadii , Vasile Bogdan Stefan , Miculescu Florin , Piticescu Radu Robert
Published: January 2024

Solid oxide fuel cells (SOFC) are electrochemical conversion devices that produces electricity directly from oxidizing a fuel and their development became of high importance to drastically reduce the greenhouse emission. Rare earth elements (REEs) are widely used as materials and dopants in controlling the ionic conductivity of solid electrolytes for SOFCs. Their criticality and high costs for separation to individual REEs lead to first studies aiming to search possible use of mixed REEs with natural occurrence as extracted from concentrates. This paper focused on obtaining sintered pellets based on zirconia doped with natural mixture of REEs extracted from monazite and study their microstructure, impedance spectra and dielectric properties vs. operating temperatures to assess their potential applications as solid electrolyte. ZrO2 doped powders with 8% natural mixture of REEs (8ZrMZ) were synthesized by hydrothermal process. ZrO2 doped with 4% Y2O3 (4ZrY) and 8%Y2O3 (8ZrY) were also obtained by the same route and used as standard materials already used in commercial SOFCs. All powders were uniaxially pressed and sintered in air, with highest densities obtained for 1400 °C. The Niquist diagrams for 8ZrMZ samples show significantly lower ionic conductivity compared to standards 4ZrY and 8 ZrY. This may be attributed to the presence of detrimental Fe and Si impurities following the mixed REE after Th and U removal from monazite concentrates and the ratio of REEs in the dopant composition affecting the ionic conductivity due to possible association of structural defects. Research works are further needed to improve the receipt for using naturally mixed REEs and asses their possible use as a competitive dopant for solid electrolytes.
Congestion: Relation between traditional DEA congestion and two-stage processes congestion
Authors: Moosavi Seyed Rahim , Bagherzadeh Valami Hadi
Published: January 2024

Congestion is a kind of inefficiency because it causes the decision-making units (DMUs) to be inefficient and reduces their output. Identifying inefficient DMUs and determining the cause of their inefficiencies has been one of the most important reasons for referring to the internal structure of DMUs and analyzing the effect of intermediate products on the subDMU’s (or stages) performance. In this paper, to characterize the cause of the DMU’s congestion, we refer to its internal structure as a two-stage network data envelopment analysis (DEA) and decompose the DMU’s congestion into black-box (BB) and two-stage structure congestion. Also, inputs have two separate and simultaneous roles; black-box inputs role and stage1’s input role, so three congestion types occur. Thus, we sought to analyze the relation between two types of initial inputs congestion, intermediate products congestion, and express their effects on BB congestion. Finally, we define three congestion definitions and model the relation between two types of input congestion, intermediate products congestion, and BB inputs congestion. Finally, a practical example illustrates the proposed method.
No-Wait Flow Shop scheduling problem: a systematic literature review and bibliometric analysis
Authors: Utama Dana Marsetiya , Umamy Sabila Zahra , Al-Imron Cynthia Novel
Published: January 2024

One of the most widely studied problems in flow shop scheduling is not allowing jobs to wait to be processed at the next stage. This constraint causes the job to be processed immediately at the next stage without waiting, so this problem is popularly called the No-Wait Flow Shop. This article aims to provide a comprehensive review of the No-Wait Flow Shop Scheduling (NWFS) problem based on a survey of published articles from 1999 to 2023. The article review is based on a systematic literature review, and bibliometric analysis is also presented based on the network processed using VOSviewer. One hundred twenty articles were collected from the Scopus database, which was reviewed based on NWFS variants, objective functions, and optimization procedures. The no-wait permutation flow shop scheduling (NWPFS) problem is a variant that researchers have widely investigated. Meta-heuristic procedures are widely applied to solve NWFS problems. In addition, the objective function of minimizing makespan is an objective function that researchers often apply. NWFS research gaps and future research trends are also presented in this paper.
How coaches design small-sided games in rugby union: a practice-based review
Authors: Wintershoven Koen , Beaven Martyn , Gill Nicholas , McMaster Daniel Travis
Published: January 2024

Background: Game-based training (GBT) is a holistic method for improving performance in team sports. Task constraints and design parameters can affect training effectiveness. The evidence on how small-sided game (SSG) design in rugby union (RU) influences outcome variables is lagging. No study has investigated the contemporary SSG practices of RU practitioners in different performance contexts.

Methods An anonymous online survey with twenty-four questions was distributed to RU training staff six times worldwide in one year through multiple e-platforms. A frequency analysis was used to assess responses and contrast it with the literature.

Results: 115 surveys were recorded. The dominant characteristics were >5 y experience (66% of respondents), head coach position (53%), New Zealand-based (77%), coaching male players (69%) on the local/school level (68%). Higher-level practitioners applied larger SSG formats with shorter duration, using more extreme pitch sizes and less tackling, for conditioning purposes primarily. Lower-level practitioners targeted fun and technique. Smaller game formats and tackling were used more in male and youth players, and on the lower levels. Further observed differences relate to practitioner role, experience, and geographical location.

Conclusion: Practitioners design SSG differently depending on their coaching background, target population, competition level, and geographical location. Practitioner education on GBT would optimise RU training practice. This study provides performance-contextual insights.
Das eigene Handeln reflektieren – Reflexionshilfe nach Fisher
Authors: Strebel Helen , Kaldewei Nicole
Published: January 2024

Das zeitgenössische Paradigma der Ergotherapie fordert, Klient*innen und ihre Betätigungen in den Mittelpunkt der ergotherapeutischen Behandlung zu stellen. Dies gelingt noch nicht immer. Fisher und Marterella entwickelten mit den vier Kontinua eine Reflexionshilfe für Therapeut*innen. Diese unterstützt die Umsetzung der Betätigungszentrierung.
Klient*innen vorurteilstrei empowern – Queerfreundliche Ergotherapie
Authors: Kloos Karina
Published: January 2024

Personen, die sich als queer bezeichnen, können besondere Betätigungsanliegen in die Ergotherapie mitbringen. Zum Beispiel, wenn sie von der Gesellschaft nicht akzeptiert werden und damit nicht ihren bedeutsamen Betätigungen nachgehen können. Ein Einblick in eine queerfreundliche Ergotherapie.
Die Stimme bewusst einsetzen – Stimmpsychologie
Authors: Wunderlich Sabrina
Published: January 2024

Bei der Stimme handelt es sich um unser wichtigstes Kommunikationsmittel. Sabrina Wunderlich gibt als Logopädin einen Einblick, welche Zusammenhänge zwischen der Persönlichkeit und der Stimme einer Person bestehen und wie man die eigene Stimme in der Therapie gezielt einsetzt.
Management of Neurologic Complications in Patients with Brain and Spine Tumors
Authors: V. Bonm Alipi , Taylor Lynne P.
Published: January 2024

Patients with brain and spine tumors represent a distinct population with unique needs. We provide a practical review of neurologic care in this group with an emphasis on familiarizing the general neurologist to the nuances of neuro-oncologic supportive care. We review the management of cerebral edema, steroid dosing, and pertinent side effects. We discuss seizure management, including choice of anticonvulsants, putative antitumor effects, and important seizure mimics like drop attacks. We review the presentation and symptomatology of stroke-like migraine attack after radiation therapy (SMART syndrome). We describe the signs and symptoms that should prompt concern for metastatic spinal cord compression, as well as both acute and definitive treatment options. Finally, we discuss the underappreciated incidence of venous thromboembolic events, particularly in patients with gliomas, and review the data on management.
Developmental or Procedural Vena Cava Interruption and Venous Thromboembolism: A Review
Authors: Bikdeli Behnood , Sadeghipour Parham , Lou Junyang , Bejjani Antoine , Khairani Candrika D. , Rashedi Sina , Lookstein Robert , Lansky Alexandra , Vedantham Suresh , Sobieszczyk Piotr , Mena-Hurtado Carlos , Aghayev Ayaz , Henke Peter , Mehdipoor Ghazaleh , Tufano Antonella , Chatterjee Saurav , Middeldorp Saskia , Wasan Suman , Bashir Riyaz , Lang Irene M. , Shishehbor Mehdi H. , Gerhard-Herman Marie , Giri Jay , Menard Matthew T. , Parikh Sahil A. , Mazzolai Lucia , Moores Lisa , Monreal Manuel , Jimenez David , Goldhaber Samuel Z. , Krumholz Harlan M. , Piazza Gregory
Published: January 2024

The inferior vena cava (IVC) and superior vena cava are the main conduits of the systemic venous circulation into the right atrium. Developmental or procedural interruptions of vena cava might predispose to stasis and deep vein thrombosis (DVT) distal to the anomaly and may impact the subsequent rate of pulmonary embolism (PE). This study aimed to review the various etiologies of developmental or procedural vena cava interruption and their impact on venous thromboembolism. A systematic search was performed in PubMed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines per each clinical question. For management questions with no high-quality evidence and no mutual agreements between authors, Delphi methods were used. IVC agenesis is the most common form of congenital vena cava interruption, is associated with an increased risk of DVT, and should be suspected in young patients with unexpected extensive bilateral DVT. Surgical techniques for vena cava interruption (ligation, clipping, and plication) to prevent PE have been largely abandoned due to short-term procedural risks and long-term complications, although survivors of prior procedures are occasionally encountered. Vena cava filters are now the most commonly used method of procedural interruption, frequently placed in the infrarenal IVC. The most agreed-upon indication for vena cava filters is for patients with acute venous thromboembolism and coexisting contraindications to anticoagulation. Familiarity with different forms of vena cava interruption and their local and systemic adverse effects is important to minimize complications and thrombotic events.
An alumina ceramic inspired high temperature wireless chipless sensor for harsh environment
Authors: Wang Bo , Gao Fei , Song Yalun , Sun Zewen , Wang Ke , Cao Shengli
Published: January 2024

This paper proposes a wireless passive temperature sensor. The sensitive material as the substrate of the sensor employs an alumina ceramic. The resonator of the sensor is a split ring, which is printed with copper on the substrate. The dimensions of the split ring resonator are optimized to improve the temperature sensitivity of the sensor. A change in environment temperature will lead to a change in the dielectric constant of the sensitive material, thus resulting in the shift of the resonant frequency of the sensor. The variation range of the dielectric constant of the sensitive material is 10.17–11.2 corresponding to 500–1000 °C. The resonant frequency of the signal backscattered from the sensor is obtained through the simulation software with HFSS. The simulation results show that the resonant frequency of the sensor decreases from 5.84 to 5.56 GHz with temperature increasing from 500 to 1000 °C and the temperature sensitivity is 0.56 MHz/°C. The high temperature sensor has the characteristics of wireless and passive operation, low profile, and high sensitivity. It can be widely adapted to a variety of high temperature and harsh environments.