bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of specific cutting energy in laser fusion cutting of an aluminium alloy
Authors: Madić M , Coteaţă M , Janković P , Trifunović M 
Published: March 2022

Abstract
Laser cutting is a non-contact, non-conventional method for contour cutting which is characterized by several process performances. The present paper aims to analyze the specific cutting energy in CO2 laser cutting of an aluminium alloy using nitrogen as an assist gas. An experimental investigation, based on the use of central composite design, was conducted to define mathematical models for the prediction of the kerf width, surface roughness, and specific cutting energy. Thus, an analysis of the effects of the laser power, cutting speed, and nitrogen pressure on the specific cutting energy is enabled. Moreover, the analysis of experimental data included the correlation between the specific cutting energy and surface roughness. Pareto optimization, considering specific cutting energy and surface roughness, was conducted to propose alternative laser cutting conditions concerning conflicting criteria.
Influence of cutting parameters on surface topography in high-speed milling of slots in titanium alloy TC4
Authors: Kurpiel S , Krupa J , Zagórski K , Cieślik J 
Published: March 2022

Abstract
This paper summarizes the experimental investigation of influence of process parameters on surface quality and dimensional accuracy of slots milled in titanium alloy TC4. Samples were milled using a 10 mm HXT coated monolith end mill for HSM milling of superalloys and titanium alloys. Process parameters, such as rotational speed, feed rate, and depth of cut were selected based on the Taguchi L9 method. After machining samples were measured, including surface quality parameters such as roughness, waviness and dimensional deviations. Measurement results indicate that within inspected parameter range rotational speed to feed ratio has a greater influence on surface quality than the depth of cut while having less influence on dimensional accuracy.
Influence of the processing conditions of 6061 aluminium alloy thick plates on the distortion of the machined finished parts
Authors: Stoicănescu M , Petre M , Popa G , Drăghici N C 
Published: March 2022

Abstract
The distortion in machining aluminium alloy parts is one of the serious challenges for the aluminium industry, and the residual stresses resulting in the processing steps are the main cause. Two 6061 aluminium alloy samples of parts, representing the same part with a special configuration, in two different stages of machining, were analysed to establish the influence of the processing conditions that can determine the changes in characteristics in the final machining process. Metallographic analysis, porosity determinations by the liquid penetrant inspection, tensile tests and determination of residual stresses by the Hole-Drilling method were performed. All the results obtained were correlated with the processing conditions of aluminium alloy plates. They indicated the role of the processing conditions on the residual stresses and distortion in the machined finished aluminium alloys parts.
Research of the dependence of geometric parameters of holes on electroerosive grinding modes with a changing polarity of electrodes
Authors: Strelchuk R , Shelkovyi O , Gutsalenko Y , Iancu C , Subbotina V , Knyazev S , Volkov O 
Published: March 2022

Abstract
In this paper are presented the results of electrical discharge diamond grinding with with difference polarities for processing various materials and calculates geometric parameters of erosion holes. The purpose of the study is to determine the volume of holes during electrical discharge diamond grinding using the mathematical method of planning experiments. The experimental plans is a combination of statistical theory and mathematical model, which is very useful in the modelling and analysing the technical problems. As a result of experimental studies, a mathematical model of the volume of holes from electrical modes of the process of electrical discharge diamond grinding was built. The mathematical formula of geometric parameters of holes obtained can be used to determine the volume of holes for different electrical quantities of discharge diamond grinding. It is found that the most significant factors that affect the geometric parameters of holes are the voltage of the igniting pulse and the pulse duration. The dependence of electrical parameters on the hybrid grinding process is investigated. There is a certain volume of holes, at which the discharge acts most efficiently, and the process performance is the most optimal. During the operation of the pulse generator, it is preferable to maintain a certain value of geometric parameters of holes, which results in an unhindered release of metal, since the effect of electrical erosion increases.
Influence of the cutting parameters on the flank surface roughness at thread whirling of low carbon steel worm shafts
Authors: Creţu G , Negoescu F 
Published: March 2022

Abstract
Thread whirling is a machining process applied mainly for its high material removal rate, ensuring the thread cutting in one single machining pass. The process presents other advantages as continuous and accurate machining, by tilting the whirling ring to the helix angle, machining long threads of deep thread parts as worm shafts, feed screws, etc. This paper presents experimental research results on the whirling process, respectively the influence of the cutting parameters specific to the whirling process on the roughness of the flank surface, in the case of worm shafts made of low carbon steel. The empirical mathematical models were obtained and discussed.
Study of filtering capacity of some ceramic composites on bentonite base
Authors: Butuc (Anghel) S , Matei S , Stoicanescu M , Crisan A 
Published: March 2022

Abstract
The paper presents the results of a study of the filtering capacity of some filters from ceramic composite materials made on laboratory installation. The filtration process involved applying a pressure gradient to the filter by means of a centrifugal pump from the filter installation. The ceramic composite materials used to make the filters have a bentonite-based matrix. To achieve the porous structure, the matrix was reinforced with SiC and Al2O3 ceramic powders and to control the pore size, additional Al metal particles were added. The stages of obtaining and characterizing the filters, respectively of testing their filtering capacity of the suspended particles from the rainwater are presented distinctly. In conclusion, the dependencies between a series of structural and geometric characteristics of the filtering capacity were established.
Concept development of an independent electronic system for vibroacoustic diagnostics of vehicles
Authors: Nitu N A , Caunii V , Bujoreanu C 
Published: March 2022

Abstract
This paper proposes the concept of electronic noise and vibration diagnostic system for vehicles that aims to avoid wrong or unreasonable replacement of their components in the repair process. Our concept for a vibroacoustic diagnostic system consists of a set of sensors that receive noise and vibration, judiciously arranged and connected to a DAQ (Data Acquisition System). This allows the ECU (Electronic Control Unit) to accurately determine, by three-dimensional detection, the area in which vibroacoustic anomalies are manifesting (due to current or incipient defects). The data storage memory works according to the first in - first out principle, retaining only significant information to save resources. Establishing a mathematical model is one of the focuses for this concept for predicting the failure of various components of the vehicle based on vibroacoustic and then developing an artificial intelligence program capable of identifying and classifying new behaviours are the steps which we follow in the development of this tool. Also, the benefits of early detection of a subassembly failure are found in increasing traffic safety.
Frequency optimization of nozzle guide vane in the low-pressure turbine system
Authors: Robak R , Szczepanik M , Rulik S 
Published: March 2022

Abstract
The aim of the article is to present the approach for modal optimisation of nozzle guide vane in the low-pressure turbine system of aircraft engine. Described analysis assumption related to the finite element model definition, meta-model estimation and optimisation process itself. Goal function has been determined basing on Campbell diagram. Typical approach to solve modal analysis for mentioned structure is full three-dimensional model that is time consuming. For optimisation purposes employed two dimensional one in order to make the process more robust (element types with support of Fourier series). This approach is reducing degree of freedom quantity and is still capable to consider non-axisymmetric structure behaviour. The article provides relationship between geometrical features of nozzle and frequency change.
Power planetary precessional transmission research regarding acoustical behaviour
Authors: Malcoci Iu , Trifan N , Ciobanu O , Ciobanu R 
Published: March 2022

Abstract
In planetary precessional reducers vibration can appear at bearings, gears, misaligned shafts, unbalanced rotors, couplings. Changes in dynamic process affects not only normal behaviours of mechanical systems but also acoustical behaviour. Regarding this aspects, regular acoustical measurements during the operating speed provide information about any necessary repairs or maintenance. Here vibration research was made by using Bruek&Kjaer Sound Level Meter 2250 Light to record Noise Rating for evaluation of global noise in dB according to ISO TC-43.
Increasing energy efficiency of counter-rotating wind turbines by experimental modelling
Authors: Cîrciumaru G , Chihaia R-A , Tănase N , El-Leathey L-A , Voina A 
Published: March 2022

Abstract
With the significant advance in exploiting wind energy, there has been a shift in research from the study of conventional systems to the study of counter-rotating systems due to additional energy input of the second rotor. The paper presents the results of the research on achieving an increase in the energy efficiency of counter-rotating wind power conversion systems. For this purpose, there have been designed different sizes of wind rotors, were 3D printed and tested in an open-circuit aerodynamic tunnel for different wind velocities and axial distances between rotors. The constructive design consisting of a smaller diameter front rotor and a larger rear rotor was chosen. The individual wind rotors were used to configure two experimental models of counter-rotating wind systems. The testing results analysis and interpretation enabled the establishing of the design and operating conditions that provide the highest power extracted from wind at 10 m/s velocity. A higher efficiency of the wind turbine system is achieved for a lower ratio between the front and rear turbines. In the case of the analysed experimental models, an increase in system efficiency of 49.14% is achieved for a 0.845 diameter ratio, and of 39.02% for 0.945 diameter ratio, respectively.
A study of effect the supporting space and tool path in sheet forming, thickness evaluation, part D
Authors: Abass K I 
Published: March 2022

Abstract
The main purpose of any sheet metal forming process is producing a product with high accuracy of the dimensions in three areas (planes). Incremental Forming (IF) is a process of redistributing the areas. Thickness is the main value and is an indicator of the complexity of the forming ability in depth. It is also an indicator value of the area that represents the product section. IF includes general plastic deformation, thus the explanation of the process by nonlinear boundary condition settings is more difficult. Especially when considering the interaction between surfaces and the frictional properties. The study involved six series that investigate the supporting space, the die radius and the forming tool path. The research presents the main results of a study for evaluating the thickness distributions and the thinning along the axisymmetric product section. The incremental forming has been considered under certain boundary conditions by reference to the ANSYS application. The study shows that the model of the simulation can expect the process track and predict the product profile and its thickness distribution. Additionally, the present paper illustrates the behavior of the forming tool during direct and indirect contact for evaluating the accuracy of IF product.
Study of roller-shoe contact during high-pressure injection pump normal operation
Authors: Iordache R C , Petrea N D , Bujoreanu C 
Published: March 2022

Abstract
Roller-shoe mechanism is very often used in diesel high pressure pumps. The most encountered issues are caused by this mechanism components which are in direct contact. Lubrication, roughness, elements dimensions and profiles, coatings, working conditions can be adjusted so that the issues are reduced. Our paper aims to identify the most critical factors which influence the roller-shoe mechanism and to calculate the contact parameters during normal engine operation. The loads applied on the components are the key factors which contribute to all parameters calculation that ensure the contact optimization. The components clearance, friction coefficients, medium contact pressure, minimum lubricant film, equilibrium temperature are some of important parameters which are the basis of a correct functioning. Analysing the obtained results, it can be observed that the lubricant film thickness can be adjusted to establish a minimum safely drive shaft rotation. Considering these results new improvements methods will be analysed for roller-shoe contact development.
Industry 4.0: challenges and opportunities in packaging logistics
Authors: Bányai Á 
Published: March 2022

Abstract
The fourth industrial revolution opened new opportunities for the development of industrial processes, as it created the opportunity for companies to transform their conventional systems into cyber-physical systems to meet the increasingly dynamic and diversified customers’ demands. Although the primary goal of the development of these cyber-physical systems is to improve the efficiency of operations and increase the quality, but energy efficiency, environmental impact and sustainability also should be taken into consideration. Packaging is a special area of production and service, where due to the significant amount of logistics activity, the design and operation of sustainable processes with low environmental impact are emphasized. Within the frame of this article, the author provides an overview of the opportunities offered by Industry 4.0 technologies in the development of packaging processes of manufacturing and service companies and outlines the challenges to be faced in the implementation of these developments.
Impact of digital twin technology on the real-time optimisation of material handling processes
Authors: Bányai T 
Published: March 2022

Abstract
The application of Internet of Things (IoT) technologies makes it possible to improve the performance of technological and logistic processes. These processes can include a wide range of IoT technologies and solutions, like cloud, fog or edge computing, intelligent tools and gentelligent products, mobile robots, 3D printing, virtual reality or last but not at least digital twin solutions. Within the frame of this article the author describes the potential of digital twin technology to improve the performance of real-time optimisation in complex logistics systems. After a short literature review, this paper introduces the conception of digital twin solutions. The model of digital twin supported real-time optimisation of an in-plant logistics system is described including the structure, the mathematical model, the solution algorithm, and the computational results. The scenario analysis of the described system validates the model and the efficiency of digital twin solutions.
Microwave method based on curve fitting method for high-precision collision frequency diagnosis
Authors: MA Gelu , LIU Yanming , ZHAO Chengwei , SUN Chao , BAO Weimin 
Published: March 2022

Abstract
In this work, the results of plasma microwave transmission diagnosis were analyzed. According to the attenuation and phase shift of the electromagnetic wave propagating in the plasma, the electron density and collision frequency of the plasma can be diagnosed. Since part of the electromagnetic wave is reflected or diffracted when propagating in the plasma, and is not absorbed by the plasma, and this part of the attenuation is still included in the measured attenuation, the attenuation is distorted. Therefore, a curve fitting method is proposed to remove the attenuation caused by the plasma reflection, thereby improving the accuracy of the diagnosis of the collision frequency. The calibration effect of this method on plasmas with different electron densities and collision frequencies is analyzed, and a diagnostic frequency band with good calibration results is given. The curve fitting method is verified by experiment and simulation. After adopting the newly proposed method, the diagnosis accuracy of collision frequency can be increased by 30%. This method can be widely used in various types of plasma diagnosis and provides a new idea for plasma diagnosis.
Collective impact: lessons from the American democratic tradition
Authors: Stewart-Gambino Hannah W 
Published: March 2022

Abstract
Collective Impact, a framework for improving social service provision first articulated in 2011, promises to improve efficiency while creating win–win cross-sector collaborations to solve the root causes of pressing community needs. This paper argues that in its current articulation, Collective Impact might deliver efficiencies but not transformative change. Positioning Collective Impact within the tradition of US democratic traditions, starting with Alexis de Tocqueville’s observations about the importance of US civil society for building an engaged citizenry, highlights specific ways to augment the framework’s transformative potential. In contrast to the neoliberal insistence that marketized social service providers are best suited for delivering efficient social service provision, this paper argues that Collective Impact leaders can take responsibility for strengthening civil society for real transformative change.
From population- to patient-based prediction of in-hospital mortality in heart failure using machine learning
Authors: König Sebastian , Pellissier Vincent , Hohenstein Sven , Leiner Johannes , Meier-Hellmann Andreas , Kuhlen Ralf , Hindricks Gerhard , Bollmann Andreas 
Published: March 2022

Abstract

Aims
Utilizing administrative data may facilitate risk prediction in heart failure inpatients. In this short report, we present different machine learning models that predict in-hospital mortality on an individual basis utilizing this widely available data source.

Methods and results
Inpatient cases with a main discharge diagnosis of heart failure hospitalized between 1 January 2016 and 31 December 2018 in one of 86 German Helios hospitals were examined. Comorbidities were defined by ICD-10 codes from administrative data. The data set was randomly split into 75/25% portions for model development and testing. Five algorithms were evaluated: logistic regression [generalized linear models (GLMs)], random forest (RF), gradient boosting machine (GBM), single-layer neural network (NNET), and extreme gradient boosting (XGBoost). After model tuning, the receiver operating characteristics area under the curves (ROC AUCs) were calculated and compared with DeLong’s test. A total of 59 074 inpatient cases (mean age 77.6 ± 11.1 years, 51.9% female, 89.4% NYHA Class III/IV) were included and in-hospital mortality was 6.2%. In the test data set, calculated ROC AUCs were 0.853 [95% confidence interval (CI) 0.842–0.863] for GLM, 0.851 (95% CI 0.840–0.862) for RF, 0.855 (95% CI 0.844–0.865) for GBM, 0.836 (95% CI 0.823–0.849) for NNET, and 0.856 (95% CI 9.846–0.867) for XGBoost. XGBoost outperformed all models except GBM.

Conclusion
Machine learning-based processing of administrative data enables the creation of well-performing prediction models for in-hospital mortality in heart failure patients.
User Perceptions of a Technology-Based Social Memory Aid for Persons With Memory Concerns
Authors: Horn Brenna , Albers Elizabeth , Jutkowitz Eric , Finlay Jessica , Mitchell Lauren , Millenbah Ashley , Mikal Jude 
Published: March 2022

Abstract
People with memory concerns (PWMC) are likely to experience social withdrawal and isolation. Although assistive technologies and memory aids are available to support PWMC and their family caregivers, few have been shown to improve social engagement. This study aimed to gain perspectives of PWMC and their family caregivers on the feasibility and utility of a technology-based social memory aid. We recruited 20 dyads of people with mild to moderate memory concerns and family caregivers to evaluate Smartwatch Reminder (SR), a notification system that provides a name, relationship, and photograph of nearby social contacts to aid in recognition. Dyads viewed a demonstration of the SR prototype, and then participated in semi-structured interviews over Zoom video conferencing from June to August, 2020. Interview transcripts were analyzed using thematic analysis, with analyses completed in August 2021. Our findings indicate that participants anticipated important benefits from using the technology, and thought the technology would be easy to use. Participants perceived that the memory aid could benefit them now and in the future by alleviating socialization-related stress for both members of the care dyad; however, certain features of SR restricted the potential benefits, such as the requirement that social contacts have the SR application, and that prompts are only provided during social encounters. Our findings will inform future technology-enabled memory aid development to improve social engagement for PWMC and support family caregivers.
Construction of a chromosome-level Japanese stickleback species genome using ultra-dense linkage analysis with single-cell sperm sequencing
Authors: Yoshitake Kazutoshi , Ishikawa Asano , Yonezawa Ryo , Kinoshita Shigeharu , Kitano Jun , Asakawa Shuichi 
Published: March 2022

Abstract
It is still difficult to construct the genomes of higher organisms as their genome sequences must be extended to the length of the chromosome by linkage analysis. In this study, we attempted to provide an innovative alternative to conventional linkage analysis by devising a method to genotype sperm using 10× Genomics single-cell genome sequencing libraries to generate a linkage map without interbreeding individuals. A genome was assembled using sperm from the Japanese stickleback Gasterosteus nipponicus, with single-cell genotyping yielding 1 864 430 very dense hetero-SNPs and an average coverage per sperm cell of 0.13×. In total, 1665 sperm were used, which is an order of magnitude higher than the number of recombinations used for conventional linkage analysis. We then improved the linkage analysis tool scaffold extender with low depth linkage analysis (SELDLA) to analyze the data according to the characteristics of the single-cell genotyping data. Finally, we were able to determine the chromosomal location (97.1%) and orientation (64.4%) of the contigs in the 456 Mb genome of G. nipponicus, sequenced using nanopores. This method promises to be a useful tool for determining the genomes of non-model organisms for which breeding systems have not yet been established by linkage analysis.