bluuebunny/crossref_metadata_2025_split huggingface dataset:
Satellite Collision and Fragmentation Probabilities Using Radar-Based Size and Mass Estimates
Authors: Hall Doyle T. , Baars Luis G. 
Published: June 2023

Most conjunctions between Earth-orbiting satellites involve unknown objects, typically debris created by explosions or collisions. This study formulates methods to estimate probabilities of collision and fragmentation for such conjunctions, which depend on the estimated sizes and masses of the unknown objects. Analysis of radar cross-section (RCS) measurements provides estimated sizes, found to be accurate at the 90% confidence level to within a factor of 0.59 for potential underestimations and to within a factor of 3.1 for potential overestimations. For satellites that experience measurable atmospheric drag orbital perturbations, combining RCS data with orbit determination ballistic coefficients provides mass estimates accurate to within factors of 0.47 to 10.9 at the 90% confidence level. For satellites with perigee altitudes above 450 km, combining RCS data with solar radiation pressure coefficients provides mass estimates accurate to within factors of 0.44 to 5.6 at 90% confidence. The collision and fragmentation risk assessment formulation accounts for these size and mass estimation uncertainties. Specifically, conjunction collision probabilities formulated as statistically expected values account for the RCS-based size estimation uncertainties. Fragmentation probabilities, which measure the likelihood of producing more than a threshold number of collision fragments, account for both size and mass estimation uncertainties.
Machine-Learning Based Rotor Fault Diagnosis in a Multicopter with Strain Data
Authors: Dutta Airin , Niemiec Robert , Kopsaftopoulos Fotis , Gandhi Farhan 
Published: June 2023

An innovative machine-learning-based probabilistic framework for online rotor fault diagnosis in multicopters is presented. The proposed scheme employs in-flight out-of-plane strain measurements at each of the multicopter booms to detect, identify, and quantify rotor faults while distinguishing them from the aircraft response to random gusts. Its robust performance is demonstrated with application to a 2-foot-diam hexacopter flying under varying forward velocity and gross weight configurations, as well as atmospheric disturbances and uncertainty. The rotor fault diagnosis takes place in two steps. First, a simple perceptron classifies the aircraft’s health condition. If a rotor fault is detected it is simultaneously identified and the fault magnitude estimation step initiates. Here, linear regression models are used to predict the respective rotor degradation values with their 95% confidence intervals. The generalization capability of the method is established with several test data under unmodeled operating conditions (not used in the training phase). The proposed framework can accurately diagnose even minor rotor faults of 8% degradation while distinguishing them from aggressive gusts of up to [Formula: see text] magnitude. The maximum fault detection time is less than 0.3 s. The health state classification and the rotor fault magnitude quantification accuracy are over 99%.
Hemodynamic Parameters in Students with Different Thresholds of Salt Sensitivity and Type of Autonomic Tone: An Observational Cohort Study
Authors: Chastoyedova I. A. 
Published: June 2023

Background. Hemodynamic parameters are interrelated with both the threshold of salt sensitivity and the type of initial autonomic tone. Available data on such relationships are insufficient. Objective — to identify the hemodynamic parameters and features in students with different thresholds of salt sensitivity and types of autonomic tone.Methods. The study enrolled 174 second-year students of Kirov State Medical University, aged 18–23, who gave consent to the survey. The study was conducted over a period of four months and included two stages. At the first stage, all participants were evaluated for the threshold of salt sensitivity. According to the results, two groups were formed: group A — students with a normal threshold of salt sensitivity (n = 127); group B — students with a high threshold of salt sensitivity (n = 39). In the formed groups, a comparative analysis of hemodynamic parameters was carried out. At the second stage of the study, after assessing the initial autonomic tone, three groups were identified: group 1 (n = 40) — students with equilibrium of the sympathetic and parasympathetic systems (normotension); group 2 (n = 104) — students with dominating parasympathetic regulation of the heart rhythm (vagotonia); group 3 (n = 22) — students with dominating sympathetic regulation of the heart rhythm (sympathicotonia). Hemodynamic parameters were also studied in these groups. Statistical data processing was carried out using Statistica Advanced 10 for Windows RU. The differences between the comparison groups were assessed using parametric Student’s t-test and non-parametric Mann-Whitney U-test.Results. A high threshold of salt sensitivity was revealed in 23% of students. When comparing hemodynamic parameters in the groups, it was found that students with high thresholds of salt sensitivity had significantly higher values of systolic blood pressure, diastolic blood pressure, pulse pressure and average hemodynamic pressure than students with a low threshold. Differences in hemodynamics in students may be caused by differences in the original autonomic tone. Thus, students with vagotonia, if compared to those with normotension, have significantly lower values of heart rate, cardiac minute output, double product, and circulatory efficiency ratio, but a higher value of the peripheral vascular resistance. Students with sympathicotonia have statistically higher heart rate, cardiac minute output, and double product values.Conclusion. The assessment of hemodynamic parameters in healthy young people in relation to the threshold of salt sensitivity and the initial autonomic tone enables the risk factors for the development of hypertension to be assessed, prehypertension (high normal blood pressure) to be identified, and preventive programs aimed at reducing the number of diseases of the cardiovascular system to be developed.
Efficacy of alveolar sandwich osteotomy with simultaneous implant placement for the management of vertical deficiency
Authors: Muthu Nivedhini Priya , Vijayarangan Sathyabama , Jeyakumar Sharmitha , Deenadayalan Vijaylakshmi 
Published: June 2023

Objectives:The aim of this present study was to evaluate the efficacy of the alveolar sandwich osteotomy with simultaneous implant placement for the management of vertical deficiency.Materials and Methods:This study was conducted in the Department of Oral and Maxillofacial Surgery, Ragas Dental College, Chennai. A total of 10 partially edentulous patients with reduced alveolar ridge height were selected for the study and sandwich osteotomy with simultaneous implant placement was done. All patients underwent radiographic evaluation preoperatively and postoperatively at 0, 1, and 3 months, respectively.Results:Of the 20 implant sites, the pre-operative ridge height varied from a minimum of 6 mm to the maximum of 8 mm with the mean of 7 ± 0.4 mm. The mean length of the alveolar ridge achieved during immediate postoperative period was 10.6 ± 3 mm and at 1st-month post-operative period it was 10.5 ± 3 and at 3-month post-operative period, it was 10.4 ± 3, all patients were followed up for a period of 3-month postoperatively.Conclusion:Sandwich osteotomy with simultaneous implant placement can be successfully used in patients with moderate alveolar deficiency to increase alveolar bone height.
Predictive diagnostics of RBMK reactor flowmeters
Authors: Zagrebaev A. M. , Popov E. O. 
Published: June 2023

At the moment, there are 8 rectors of the RBMK type in operation. The safety of their operation is ensured by monitoring devices for key indicators. In this article, the main attention is paid to the control of the coolant flow through the fuel channel, carried out with the help of ball flow meters of the STORM-32M and STORM-8A types. During operation, there is a gradual wear of the raceway and the ball, which leads to the appearance of a negative error in the device, in other words, the readings become underestimated. In this regard, as well as due to the widespread use of ball flowmeters at nuclear power plants, the task of diagnosing the state of flowmeters is urgent. One of the approaches to determining the flow rate of the coolant is an approach based on the measurement and use of information about the activity of the coolant by the tightness control system of the fuel element shells (SKGO). The use of this radiation approach to control the flow of coolant has its advantages and difficulties. The advantage is that real experimental information about the presence of a coolant in the fuel channel is involved, and the difficulties are associated with receiving and processing the signals of the SCGO in real time and, consequently, with low efficiency of solving the problem. In this paper, we propose a method for predictive diagnostics of the flow meter condition using the design features of the multiple forced circulation circuit (CMPC) of the reactor. The adaptive parameter of the model was selected as a diagnostic parameter. Studies have shown that the increase in time variance in experimental flow values has a clear effect on the selected diagnostic feature , as a result of which it can be said that the observation of this kind of variance change in experimental data can serve as a sign of a malfunction of the flow meter.
Arc stability study at the limit mode of welding with coated electrodes
Authors: Burdakov S. M. , Tsuverkalova O. F. , Zayarov Yu. V. , Postoy L. V. , Tkachev V. G. 
Published: June 2023

This paper shows the results of experiments to study the effect of the auxiliary voltage with frequency fi= 40000Hz on the stability of arc discharge at the limit mode of the welding process with single, coated electrodes. This effective method of connecting rolled and prefabricated elements of metal structures has found widespread use in their installation, manufacture and repair in the construction of various facilities: industrial and civil purposes, thermal and nuclear power facilities for responsible purposes. In this regard, the increase in the quality and technological, strength parameters of welds, the productivity of the manufacturing metal structure process, is largely associated with welding modes and an increase in the stability of arc discharge as an important element of the system: "power source-arc-welding tub-product." Improving the performance of the welding process under consideration is particularly important under mounting conditions in conjunction with its stability is an important task on the agenda. When performing the study, the following criteria and their values regarding the stability of the welding arc were taken into account, such as: lexpl - rupture length in mm, coefficients of variation: KV(Iwd) - welding current, KV(Uwd) - voltage, qt - constant time, as well as their numerical values were obtained. The obtained numerical values of the above criteria were obtained based on the analysis of graphs (oscillograms) of the dependence of the electric current (Iwd, A) and the voltage (Uwd, V) of the arc on the time of the process duration (t, sec). The obtained results of the analysis indicate an increase in stability, a decrease in inertia of the deviation of the resistance (conductivity) of the welding arc when the auxiliary voltage is applied with a frequency of fi = 40000Hz at the limit mode of welding with coated electrodes.
Peranan Koperasi Dalam Pengembangan Sistem Agribisnis Kakao (Studi Kasus: Koperasi Perkebunan Kakao Bireuen)
Authors: Jamil Muhammad , Budi Setia 
Published: June 2023

There is still great potential for the development of cocoa plants in Kabupaten Bireuen is a great opportunity to improve cocoa agribusiness in a sustainable, one of them is through institutional roles. However, the Kabupaten Bireuen government still has several problems in running the cocoa agribusiness system starting from the upstream subsystem to support services. Problems in the upstream subsystem and farming, namely farmers have not been able to fully implement the frequent harvest system, pruning, sanitizing and fertilizing (PsPSP) as well as fermentation. Even though the Bireuen Cocoa Plantation Cooperative has provided trainings related to the PsPSP system and the fermentation. This study aims to determine the cocoa agribusiness system in Kabupaten Bireuen and to find out the role of the Cocoa Plantation Cooperative that has been carried out so far. The sample criteria in this study were 34 cocoa farmers who were active members of the Bireuen Cocoa Plantation Cooperative. Data analysis in this study used a qualitative descriptive method with data measurement using a Likert scale. The results showed that the cocoa agribusiness system in Kabupaten Bireuennot well integrated, while in general the role of cooperatives in the development of the cocoa agribusiness system is large with an index value of 69.92%.The role of cooperatives in aid distribution activities is categorized as large with an index value of 73.94%,training activities have a big role with the category 79.65%, mentoring activities have a big role with an index value of 67.12% and the collection of results has a small role with an index value of 58.97%.
Self–Brand Connection and the Decision to Purchase Counterfeit and Original Luxury Brands in Tanzania
Authors: Frida Thomas Pacho  
Published: June 2023

The research employed the method of Perceived Counterfeit Detection (PCD) to determine the significance of individuals' considerations in determining their decision to purchase original luxury brands. The study explored the relationship between self-brand connection and the purchase of counterfeit luxury brands, and also, evaluated the influence of economic benefits. The research was conducted through a survey of prospective luxury goods consumers, both original and counterfeit, in six malls located in two cities using a questionnaire. A sample of 930 participants was used, and the hypotheses were tested using a structural equation model. The findings indicate that an individual's self-concept might play a role in deciding whether to purchase an original or counterfeit luxury brand. It is noteworthy that the Perceived Counterfeit Detection completely influenced the relationship between self-brand connection and the decision to buy an original luxury brand. Furthermore, the study discovered that economic advantages intensified the inclination of consumers to buy counterfeit products in emerging economies. This contributes to the Social Identity Theory, suggesting that in scenarios heavily influenced by personal development, social pressure from one's social group might override individual moral considerations such as self-brand connection. The findings of this study hold considerable importance for managers and marketers as they enhance their comprehension of the influential role that individuals play in influencing the purchase of luxury brands. Marketing strategies need to consider the influence of family and social groups on buying choices, and advertisements should be customized accordingly.
Development of Physics LMS Based on Science Literacy Related Energy Content in Agricultural Context (Farmer)
Authors: Herawati  , Setiawan Andhy , Hidayat Arif 
Published: June 2023

Farmer is a Physics learning media that functions as Learning Management System (LMS) to organize, manage, and deliver subject matter on the concept of energy and its changes related to work, changes in mechanical, chemical, electrical, heat and renewable energy on the basic techniques of plant production processes which refer to a science literacy-based learning flow with a web format for the vocational school of Agriculture. The purpose of this study was to analyze the concept of Energy and its changes in Agriculture that are used in the LMS Farmer. The Material of Energy and its changes in Agriculture in LMS farmers were developed using the ADDIE model 1) Analysis Phase; 2) Design Phase; 3) Developed Phase; 4) Implementation Phase; 5) Evaluation Phase. This research used the qualitative method. The non-test research instruments included material validations by four material experts consisting of two physics experts, one teacher and one Agricultural material expert. The data analysis techniques included descriptive statistics. The results showed that the material of Energy and its changes in Agriculture on LMS Farmer, based on the assessment by four experts lies in the “feasible” category. The conclusion of this study is that the material of Energy and its changes LMS Farmer in the feasible category so that they are feasible to be applied in physics learning for vocational schools majoring in Agriculture.
A Comparison of Oak Leaf and Fescue Hay Infusion-Baited Gravid Trap Collections—An Analysis Steeped in the Context of La Crosse Virus Vector Surveillance Effectiveness
Authors: Sither Charles B. , Sither John M. , Byrd Brian D. 
Published: June 2023

ABSTRACT
Neuroinvasive La Crosse virus disease remains the primary cause of pediatric arboviral encephalitis in the USA. In spite of the persistent public health burden, there are limited entomologic surveillance options that target both native and invasive La Crosse virus (LACV) vectors. In this study we used Reiter/Cummings tacklebox gravid traps to compare white oak (Quercus alba) and hay (predominately Festuca arundinacea) infusions within a LACV-endemic area of western North Carolina. Paired gravid traps (approximately 1,728 total trap-hours for each infusion) yielded 485 mosquitoes, with 3 species (Aedes japonicus [n = 265], Ae. triseriatus [n = 156], and Culex restuans [n = 45]) accounting for 96.1% of the total collection. The hay-infusion traps collected 2.5 times more Ae. triseriatus and 1.3 times more Ae. japonicus than the oak-infusion traps. The sum differences in overall collections for these 2 species by infusion type were statistically significant (χ2 = 9.61, df = 1, P = 0.0019). Poisson ratio tests to compare capture rates suggest that hay infusions were more effective for capturing Ae. triseriatus, but that hay and white oak leaf infusions had equivocal capture rates for Ae. japonicus (an invasive LACV accessory vector) and Cx. restuans (an enzootic West Nile virus vector). These results are discussed in the context of operational considerations for LACV vector surveillance.
Climate change risk perceptions, vulnerability, and adaptation in high altitude farming regions of Hindu Kush Himalaya
Authors: Asad Saeed Ahmad , Abid Muhammad , Ahmad Ishfaq , Thapa Gopal , Dendup Tashi 
Published: June 2023

ABSTRACT
Hindu Kush Himalaya (HKH) is highly vulnerable to climate change, but there is the least understanding of the impacts of climate change. This study explored local climate change risk perceptions, vulnerability, and adaptive responses in the three HKH countries, Pakistan, Nepal, and Bhutan. For this purpose, 379 farm households from low, medium, and high elevations in the study districts of Rasuwa in Nepal, Gilgit in Pakistan and the Central District in Bhutan were surveyed. A semi-structured digital survey was used for data collection. Further, the study used the IPCC climate vulnerability framework to explore the farm-level vulnerability to climate change in three HKH countries. The study revealed that farmers in the study areas strongly agreed that the climate was changing in the region with high summer temperatures and increasing frequency and intensity of weather-related extreme events. Increasing poverty and limited institutional services make farmers more vulnerable to climate risks. Farmers reported reduced agricultural productivity and decreased revenue caused by climate change. Crop yields at high altitudes were slightly higher, but only because of multiple cropping triggered by weather patterns. Lack of information, resources, and institutional support significantly hamper the farmers’ adaptive capacity. A small fraction of the farmers adopted improved crop varieties and land management. The study recommends improving outreach and institutional services, especially climate-specific farm advisory services in HKH countries.
Career Guidance System Using Machine Learning
Authors: Panthee Subiddhya , Rajkarnikar Sudikshya , Begum Rabiya 
Published: June 2023

Career Guidance System is important for students going through academic and pursuing courses to access their capabilities and identify their interests. This paper mainly concentrates on career guidance through personality prediction. It helps them decide which job role suits the best based on their performance and other evaluations. The system will predict the Big Five personality, and VAK learning type of the users through data collected from web-based questionnaires. The system recommends different career choices based on their answers. Machine learning algorithms will be used to check the performance of the system and validate the result.
Dark Matter as Dimensional Condensate
Authors: Goldfain Ervin 
Published: June 2023

_Fractional statistics_ (FS) is a generalization of the spin-statistics theorem and mixes bosons and fermions in a non-trivial way. Mixing is controlled by a continuous parameter \(0\le q\le1\) and the ordinary statistics is recovered in the limit \(q=1\) . We have argued some time ago that the onset of FS occurs in a spacetime endowed with minimal fractality, whose ground state is the _Cantor Dust_, an early Universe phase created by topological condensation of continuous dimensions. Recent studies on \(q\) - bosons reinforce the hypothesis that Dark Matter is the relic of Cantor Dust left over from the early stages of cosmological evolution. The take-away point of this brief note is the growing support for the minimal fractality of spacetime and its ramifications in foundational physics.
Aerodynamic Analyses of Variable Geometry Asymmetric Supersonic Nozzles
Authors: Sibanda Bakisanani 
Published: June 2023

<p>The objective of the research is to develop a two dimensional supersonic nozzle with adaptable geometry that will allow a range of exit supersonic speeds ranging from Mach 1.29 to 4. The uniformity of the exiting air stream was the primary performance indicator. The asymmetric geometry is intended to be used in supersonic wind tunnels were uniform exit flow and a range of usable Mach numbers increases the utility of the tunnel. Numerical tools using the method of characteristics were developed using MATLAB to create an initial inviscid nozzle profile. Geometric constraints lead to the development of a two nozzle approach. It was found that an inviscid asymmetric nozzle geometry derived through the method of characteristics could be successfully adapted to create asymmetric nozzle profiles to include viscous effects. Numerical methods employing RANS solvers were required to adapt the asymmetric nozzle geometry. The uniformity of the exiting air stream was highly dependent on the downstream nozzle geometry. With effective geometry adaptation, the average variation of exiting nozzle velocity for a viscous flow was reduced to 1% and no less. </p>