bluuebunny/crossref_metadata_2025 huggingface dataset:
Smart Pet Feeder
Authors: Koley Soumallya , Srimani Sneha , Nandy Debanjana , Pal Pratik , Biswas Samriddha , Sarkar Dr. Indranath
Published: March 2021

At present automated technology is a trend and is easy to access, user friendly and easy to monitor. Having pet can be an enjoyment in our life. In this paper a prototype has been proposed to solve the problem of providing food and water for all types of pet when owner is residing away from home such as lockdown situation. By the application of this prototype, the owner can supply food and water to the pet at their preferred scheduled time. The system proposed is controlled through an ATMEGA32 Microcontroller. A conical structure created using ply board (collected from waste material) for reserving the pet’s food. A servomotor has been interfaced to control the outflow of the food through a PVC pipe connected to the bowl. The bowl is placed on a load cell to inspect the weight of food. The owner can assign the timing and quantity of food through a keyboard to supply food depending on the instantaneous weight of the food in the bowl. By using float sensor water level in the container has been monitored and refilled.
Self sanitizing voice controlled intelligent wheelchair
Authors: Nath Sudarshan , Debnath Sourav , Mukherjee Nilay , Mukherjee Swagata , Chakraborty Amaresh , Ghosh Mr. Prolay
Published: March 2021

We have developed a “Self Sanitizing Voice Controlled Intelligent Wheelchair.” The wheelchair will be totally voice controlled. There will be sanitizing system for both the wheelchair and the surrounding area. In Covid-19situation, maintaining social distance is very important. Keep this in mind we will add the alert system in the wheelchair. When any person will come very close to the wheelchair it will announce a voice alert. Also this wheelchair will climb the stair without anyone’s help. This wheelchair will be developed for the disabled person as well as for the Corona patient. The assistant of the disabled person or the disabled person can be Corona affected. As the wheelchair is voice controlled, it will not need someone to push the wheelchair. It will also helpful to carry the Corona patient, where the nurse or assistant can move the wheelchair by giving voice command from a safe distance. The wheelchair will have voice controlled sanitizing system where it will be able to sanitize itself and its surrounding area. After carrying the Corona patient this wheelchair can be sanitized without going near to it. Also this wheelchair will help to sanitize the patient’s room. So, before entering the patient’s room, by giving voice command the room can be sanitized.
“We Care”: An IOT enabled tracking system for COVID affected patients
Authors: Saha Dwaipayan , Mukherjee Indrani , Roy Jesmin , Chatterjee Sumanta
Published: March 2021

In this crisis of deadly worldwide pandemic of COVID – 19, thousands of people are getting admitted in the hospitals, with the hope of getting cured. In this point of time, doctors, nurses, and the other medical staff have a lot to pressure and stress to deal with such a large number of patients. Once admitted, family members of the patients don’t get regular updates about the patient. After considering all these problems, we have proposed an idea entitled, “WeCare”, which can suitably be a solution to mitigate such problems. This will be basically, a tracker worn by a patient once admitted in the hospital. This tracker has sensors to sense various vital body parameters such as body temperature, heart rate, pulse rate and most importantly, the oxygen level in the body of the patient. The entire information is stored in the database of the hospital. Trained machines will be there to give an alert when the condition of the patient deteriorates, and immediately help will be arranged. Adequate provisions and arrangements are also made which will help the family members of the patients to keep a track of the health of the patient through a mobile app.
Smart Shoe Sanitizing Device
Authors: Bhunia Pabitra Kumar , Mondal Poulami , Biswas Pratnadeep , Chatterjee Sumanta
Published: March 2021

People of our country are searching for all kind of protection against the virus which has been spread in all countries, according to surveys it is known that coronavirus keep active on the metallic grounds but on the other hand it can remain on shoe for three to five days. As plastic, leather, and rubber are the good transporter of viruses so daily requirements made by these materials are needed to be sanitized. If a person goes to an infected place or sneezes or speaks in front of another person can be infected easily by the globules spread over the shoes. Also, as our shoes come in contact with most of the dirt and germs, it is another reason for growing corona along with another virus. For this which virus and bacteria stay stick with the sole of the shoes can be carried to home. So, to fight against this situation, this paper proposed a smart IoT based Shoe Sanitizing System. Our proposed system will detect and remove the bacteria or virus by liquid spraying sanitizer along with the light of UV and at last, the shoes are dried with the air of DC. We can monitor and control the system over the Wi-Fi or internet by the implementation of the Node MCU and 4G GSM module. We have constructed this system to be carried out on the entry gates and doors. Through this device, a passer-by can avoid destroying the pandemic and also lower cost.
Impact of asymmetric dielectric on the performance of TFET
Authors: Bhattacherjee S. , Barman A. , Majumder R.
Published: March 2021

In this work first time we propose the dielectric modulated TFET model and observe the impact of asymmetry on different parameters like ON current, OFF current and intrinsic gate delay for a wide range of dielectric constant by simulation technique. We obtain satisfactory result for ON/OFF current as well as intrinsic delay by applying asymmetric dielectric. Our observation shows that by using the material of dielectric constant in the range of 5 to 20 at source side of TFET gives the best result for ON/OFF current as well as intrinsic delay.
GPS Tracking, QR code Scanner Based Application to Help the Health Workers and Common Citizens during Covid-19
Authors: Biswas Suparna , Banerjee Wriju , Saha Sanchari , Maity Saswata Sundar , Bhattacharyya Tathagata , Sadhu Subhrajyoti
Published: March 2021

At the end of 2019, a novel Corona Virus surfaced as a pathogen and eventually resulted in a pandemic situation. The infection rate unleashed havoc worldwide firstly affecting European nations then the US. So, in this paper we proposed a software application which intakes user data to calculate the threat based on the merits of reconducted survey which prompts the user to check if they are undergoing any of the medically proven symptoms and sends it to the local municipal clinic. This in turn will minimize the need for medical workers to visit door to door constantly at risk of getting infected. This software is equipped with features like GPS tracking, threat level predictor, contamination graph it also determines medicinal urgency etc. Basically, our system is supposed to assist the day to day workers and visit places in scenarios of maximum urgency. This proposed system is used to prevent allowing likely symptomatic as well as asymptomatic users to enter in the hotspot regions’ public places such as malls and markets. The application will generate a unique QR code for respective users which will depict their merit based on mandatory survey that whether that person is affected or not. The QR code can be used in order enter the public area places where scanners are placed.
A Regression Model Frame with IoT to Predict COVID Zone
Authors: Pati Subhajit , Mallick Sourav , Chakraborty Snehashis , Kaur Rajbinder , Dhar Moloy , Jena Amrut Ranjan
Published: March 2021

In this paper, we are planning to build an application through which victims of Covid-19 can put their data. Once an effective data set is built, the application is capable to predict a COVID-19 zone based on these data by using a regression model. The parameters of the data set will be:

1. How many times a person visited outside.

2. City of the person, who visited abroad recently if yes then which country (take the ratio of victims to their population density as a parameter), if no then we will put a zero.

3. The cases in their home town by simply accessing their location (take the ratio of victims to the population density of that area).

4. Once data set is built, then train a regression model to predict the chances of a person being a victim of Covid - 19 and once that information is available we can simply observe in which area the no of suspected no of people is greater through which we can tell the chance of an area being affected by this situation.

5. Although parameters of the data set are limited now but we are planning to add more so that more accurate models can be built.
Design and Realization of Low profile Compact Wideband Monopole Printed Antenna for C and X band Application
Authors: Ghosh S , Sarkar I , Chowdhury S , Dutta S , Dey P , Majumdar S , Ghosh A , Sarkar P P , Sarkar D C
Published: March 2021

A compact low profile printed line-fed antenna presented for wideband in C and X band range. The antenna proposed in this paper has wider impedance bandwidth at well separated resonance frequencies. The antenna has a circular slot in the radiating patch embedding a parasitic circular patch. A grounded metallic strip extended from the ground plane connected to the middle of the parasitic patch through a shorting pin for improved impedance bandwidth. Rectangular patch has a compact area of 32 mm X 30 mm. thickness of the annular-slot in the patch and width of grounded strip have been varied to provide the surface waves within the microstrip antenna responsible for large frequency ratio. The simulated result shows that fractional impedance bandwidth of about 660 MHz, 1.54GHz, 440MHz centred at 2.87GHz, 6.17GHz and 8.15GHz respectively. To maintain the impedance bandwidth within C and X band operation, parametric study has been reported. The antenna shows absolute gain 1.12 dBi at 3.19 GHz. The proposed wideband slot antenna has been studied and designed for simulation results of return losses; radiation patterns, realized peak gains, and efficiencies of the antenna are presented. The projected antenna is appropriate for the applications in C and X bands such as medical and industrial heating applications (5.725 - 5.875 GHz), mobile satellite sub-band (7.975-8.025 GHz), Radiolocation for Military requirement for land, airborne and naval radars (8.5 GHz- 10.5 GHz).
Prevention from Gas Devastation
Authors: Datta Sanghita , Sah Ankita , Gautam Sidharth , Das Upamita , Maity Dr. Saikat
Published: March 2021

LPG leakages are the most common issues found in household and gas plants. This issue is life threatening not only for the humans in the vicinity but also for the surrounding areas. The idea behind our project is to save the lives of those innocents who can get affected due to the carelessness of certain people. So, as soon as the gas gets detected by the system, the concerned people around will receive messages as well as the alarm rings.
A Novel Medical Image Encryption using Cyclic Coding in Covid-19 Pandemic Situation
Authors: Bose Barsha , Dey Diptana , Sengupta Anupam , Mulchandani Nikita , Patra Anirban
Published: March 2021

During this Covid - 19 pandemic situation, encryption of medical images takes a major role in medical information systems as well as in telemedicine. However according to government rule, it is essential to hide the information of the patients. Recent development in computer network enhances a lot of facilities in communication area. Unfortunately, hackers are misusing this facility and always try to attack on the transmitted information in insecure network. For secure transmission of medical images, it is essential to encrypt the information before transmitting. In this communication, we are going to present a novel approach of medical image encryption using cyclic coding. We have proved that it is quite difficult to decrypt the original information from encoded data in one common mode of attacking-chosen ciphertext attack. Moreover, we have proved the effectiveness of the encryption using correlation coefficients. Our proposed scheme is suitable for efficient encoding of multiple medical images.
Sustained Pacemaker System Powered From PIEZOELECTRIC TRANDUCER
Authors: Barman A. , Dutta T. , Dey D.
Published: March 2021

It endeavours to postulate a smart, economical power supply system for pacemakers based on the principle of power harnessing using piezoelectric effect, on the contrary to the existing battery powered system, resulting an enormous reduction in pacemaker cost. The proposed system will use heart vibrations to generate power from piezoelectric transducer and provide a steady DC output to the pacemaker system, reducing or omitting the need of pacemaker replacement. The proffered system also has a scope of providing a warning by pre-detecting the possible threat of future heart-disease. The general objective of the project is to replace the need of expensive battery by harnessing power from heart vibrations to drive the pacemaker system to measure the real-time Blood Pressure of the patient and to produce an alarm by pre-sensing the probability of possible heart-failure or heart-disease.
Screening of potential anti-HIV compounds from Achyranthes aspera extracts for SARS-CoV-2: An insight from molecular docking study
Authors: Dutta Tanmoy , Ghorai Sajal , Khan Abdul Ashik , Baildya Nabajyoti , Ghosh Narendra Nath
Published: March 2021

Till date millions of people are already infected by the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2). Situation is getting worse day-by-day due to lack of efficient Drug or Vaccine. It is already established that few compounds ofAchyranthes asperaextract have significant anti-HIV activity. Present study examines inhibitory efficiency of 8 anti-HIV compounds ofA. asperaextract against SARS-Cov-2. Angiotensin converting enzyme-2 (ACE-2) of Human body, RNA-dependent RNA polymerase (RdRp) and Main protease (Mpro) of SARS-CoV-2 have been chosen as targets for this study. The binding energies and inhibition constant values of these 8 compounds have been compared with the three drugs (Chloroquine, Hydroxychloroquine and Remdesivir). Most of the compounds showed good binding energies and inhibition constant values compared to the drugs. Excretion and Toxicity (ADMET) profile also reflected that the hits from our analysis are safe. According to the molecular docking study, among these 8 anti-HIV compounds, Oleanolic acid has the highest binding affinity and low inhibition constant value with the three proteases. So, we believe that this study will help in therapeutic efforts against SARS-CoV-2.
Study of Graphene field effect transistor (GFET) for chemical sensing application.
Authors: Bandyopadhyay M , Chakraborty G , Roy S , Bhattacharjee S
Published: March 2021

This paper presents a model that provides the transfer and output characteristic of a grapheme FET transistor. This model also provides close form inquiring expressions for the drain current, trance conductance of the device. In this paper we have investigate the transfer characteristic curve for chemical sensing application. In this present scenario this work proposes to develop a superfast mycotoxin sensor based on Graphene field effect transistor (GFET) using standard microelectronics technology. GFET would be able work in liquid and also in the biological substances. In this work, we will use the simulation program to explore the performance of GFET. The GFET sensor will be integrated to IoT and mobile phone platforms. This study will show that the fully integrated mycotoxin sensor with high sensitivity, fast response, and high dynamic range of toxins concentrations is feasible by proper GFET functionalization.GFET was modelled and simulated Using MATLAB software Introduction.
Mechanism to disinfect money to prevent COVID-19
Authors: Saikat Pal , Chatterjee Sarthak , Sankha Dey , Chowdhuri Swati , Neogi Biswarup
Published: March 2021

Currency notes and coins play an important role in daily needs for the human being across the world. These currency notes take a major role for spreading the Corona virus infection and circulation of the currency notes enhance some infectious disease like COVID-19. A new prototype is introducing here to prevent the problem that is spreading of corona virus by hand to hand money transfer across the world. This paper is about preventing the spreading of corona-virus through currency by developing automatic, portable alcohol-based money disinfector. The prototype disinfects both currency notes and coins by ethyl alcohol.
Fingerprint Door Lock System with Temperature Sensor
Authors: Poddar Arkojyoti , Roy Somrup , raha Subhasish , Thakur Kusal , Dasgupta Tamojit , Maity Dr Saikat
Published: March 2021

This paper describes an advanced security system designed for the purpose of door locking. Keys can be stolen but not our identity. Also, overriding a fingerprint sensor door lock is really tough so the system guarantees high security. Technology is getting upgraded day by day and is accessible by any educated and technical person with minimum of computing skills. Now technology is nothing but advancement of the particular field of science irrespective of the fact whether it is related to computer or not. With the advancement of technology, our security is at constant threat to get away with this problem, we developed this security system completely based on biometric authentication. For implementing this project, we will be using the Arduino UNO, a fingerprint sensor, a servo motor, and some other hardware devices. Alongside the working of this fingerprint-based system, we shall also discuss about how our project can be helpful to the society during this epidemic.
A Study during Lockdown Period Based on AQI over Indian Mega cities during COVID-19
Authors: Chakraborty M , Debnath S , Ghosh S
Published: March 2021

The COVID-19, the most deadly challenge human being could have imagined, has become a reality now and the whole world is passing through the worst pandemic situation. From the challenges of invention of life saving vaccine or medicine to keeping economy at right track are the most talked about hurdles in front of all of us. But if we look at the other side of the coin, the blessings that came in form of disguise could be realised. The paper emphasizes on those aspects during lockdown that was imposed in India for three weeks initially that is 24th March to 14th April 2020 and later on till 3rd of May 2020. As a result of this forced restrictions, pollution level in whole India, specially in metro or mega cities where large population and pollution is a deadly combination, drastically changed. For analysing air quality, the metro-cities like Delhi, Kolkata, Chennai and Mumbai has been investigated here. The pollutant parameters PM2.5, SO2, NO2, along with CO, O3 and overall AQI (Air Quality index) has been collected and comparative study was done before and after lockdown and even for the year 2018 and 2019 too. Reduction of level of pollutants in significant amount of percentage is observed for all the metro cities where variation of reduction level from city to city is also significant. The effectiveness of lockdown over different metro cities are also very significant, pointing towards alertness of local people and population concentration. Finally, the study can be used in future as case study for controlling pollution with controlled lockdown and this can be practiced in future once or twice yearly to save our motherland.
Investigation of deep cryogenic treatment of Steels for medical tooling applications
Authors: Biswas P. , Ghosh S. , Sarkar A. , Roy N.G.
Published: March 2021

Hardened steels, which are resistant to corrosive chemical environments, are quite popular in the medical fields for various tooling applications exposed to low temperature. Using deep cryogenic treatments hardness and corrosion resistance of steel can be significantly improve for better compatibility of steels in biomedical applications. The present investigation examines the microstructure and evaluates hardness values of deep cryogenically heat treated AISI M2 steel. Studies on cryogenically treated tool steel show microstructural changes in the material can influence the life of the tools significantly. Through pertinent analyses of the experimental results this investigation infers that deep cryogenic treatment of AISI M2 steel increases the hardness of specimens marginally with the increase in the number of tempering cycle. The treatment further provides opportunity to exploit the possible use to hardened steels in robotic arms operative at low temperature research labs.
Influence of mobility, population and effective reproductive number (R) on the transmission of Coronavirus
Authors: Maithani Rajesh , Pandey Jitendra K , Kumar Anil
Published: March 2021

The present investigation reviews the potential causes of the novel Corona virus (COVID-19) spread based on various parameters studied. At the onset of COVID-19 pandemic there were number of parameters that were believed to be the dominating factor, and the demand of present scenario is to determine the potential variables that enhances the virus transmission. The social distancing is the main weapon to fight against the coronavirus, keeping this in mind the impact of mobility is analyzed. In addition to this the population density and the effect of temperature and humidity is studied on the present pandemic.
Educational Assistance Bot
Authors: Roy Arindam , Singh Dharmpal , Sahana Sudipta
Published: March 2021

An Internet bot performs automated tasks over the Internet. This software application is also known as a web robot or robot or simply bot, Typically, bots runs simple and structurally repetitive tasks, at a much higher rate than would be possible for a human alone. This effort is to help the users by providing all the basic student’s academic details like subjects, faculty names, books, notes and routine according to their need using bot. Users can also get other information like fees structure, library inventory list, calendar etc. Additional information like top educational sites, most trending educational videos etc will be regularly updated by the admin. This is an all-in-one application which can also be used to fetch and update information which is purely related to COVID-19.
A study on students’ responses on digital teaching methodology under covid-19 perspectives
Authors: Chowdhury Subhajit Basu , Mahapatra Shubankar
Published: March 2021

The whole world is facing unique Pandemic situation due to the outbreak of corona virus since last couple of months. There is a consistent situation of panic and fear everywhere. India too is facing same situation and amidst the prolonged phases of lockdown, everything seems to come to stand still. Economy is severely hit by this pandemic situation. Various Industrial sectors have either turned sick or closed down due to demand crunch and lacks of people are losing jobs, resulting unprecedented crisis in the society. In education sector too, there is paradigm shift in teaching and learning methodology. The students cannot attend traditional class room teaching due to close down of schools and colleges. In higher education too, online classes are going on and the college students have no options but to attend virtual mode of classes and face online examinations in many instances. The students’ community is altogether experiencing a new and non-familiar teaching and learning environment. This research paper was written based on the online survey of higher education students in few districts of West Bengal. The survey was undertaken to unearth the responses of the students’ community to this digital teaching methodology, which they are facing. The responses of students to this new and unfamiliar digital teaching and learning environment were shown in the findings section of this paper.
Estimation of flood-damaged cropland area using a convolutional neural network
Authors: Lazin Rehenuma , Shen Xinyi , Anagnostou Emmanouil
Published: March 2021

Flood damage to croplands poses a significant threat to global food security. Effective disaster management to cope with future climate change, especially extreme precipitation, requires a robust framework to estimate such damage. For this study, we develop a model based on a convolutional neural network to estimate the area (in acres) of cropland damaged by flooding at the county level. Then we demonstrate the model’s performance for the period 2008–2019 over corn and soybean fields in the midwestern United States, which suffer frequent damage from recurrent flooding. We fed the network with remote sensing images and weather fields and divide the growing season into two windows, the early season (May–June) and the late season (July–November) for better performance. The results show mean relative error within

±

25% and relative root mean square error within 35%–75% in majority of the counties for most years. Finally, we show that the model forced with meteorological variables alone can provide acceptable accuracy, which indicates it can be applied to forecasting crop damage area in the upcoming season or the studying of future climate impact on crop productivity. In principle, the model can also be applied to food security assessment at the global scale using available records.
Fatigue behaviour of thin Fe-Si steel sheets for electric motor production
Authors: Fortese G , Nicoletto G , Riva E
Published: March 2021

The on-going evolution toward electric/hybrid traction requires the development of high-performance electric motors. The rotor of electric motors is made from a stack of thin steel sheets and a complex configuration of magnets. Electric steels are typically Fe-Si alloys where Si addition controls grain size. Mechanical durability assessment of electric motors is based on the fatigue performance of Fe-Si steels.

This contribution reports a thorough mechanical characterisation of a Fe-Si alloy in the form of thin (i.e. 0.2 mm) sheets. Numerous tensile tests were performed to characterize the reference static properties and their respective scatter. A suitable fatigue testing procedure for thin sheets was developed and used in an extensive campaign aimed at investigating the directional fatigue behaviour of the Fe-Si steel. Comparison with literature data confirms that the fatigue response of thin sheets is affected by different factors related especially to the method of extraction.
Crack detections in fatigue loaded structures by means of low-cost Thermoelastic Stress Analysis setups
Authors: Cappello Riccardo , Catalanotti Giuseppe , Pitarresi Giuseppe
Published: March 2021

The work presents the results of an experimental evaluation of the thermoelastic signal on fatigue loaded single-edge-notched and tensile samples made of stainless steel. The thermographic signal is acquired by a micro-bolometer sensor Flir A655sc. The evaluation is performed varying the loading frequency and sampling frequency. The thermoelastic signal is evaluated by a Discrete Fourier Transform algorithm accounting for the influence of spectral leakage. Two different crack tip search algorithms are applied and compared: a grid method with pixel and sub-pixel accuracy and a sub-pixel pattern search method, both based on least square fitting of the Williams’ Series stress function. The two algorithms are also evaluated in terms of accuracy, automation level and computation timing. The SIF evaluated by the Micro-Bolometer is corrected by a specific camera dependent calibration procedure, and the influence of the number of points used in the least square fitting on the final value of the SIF is investigated in order to obtain the fastest and reliable setup conditions for an automatic full fatigue crack growth characterisation with a non-contact and low cost Infrared camera system.
Effects of FOD on fatigue strength of 7075-T6 hourglass specimens
Authors: Arcieri E V , Baragetti S , Lavella M
Published: March 2021

The term “Foreign Object Damage (FOD)” refers to the damage associated with the impact of particles on aircraft engine components that causes changes in fatigue strength as a result of induced stress concentrations, residual stresses and microstructural changes. This paper presents the Finite Element (FE) models created to study the stress field induced by the impacts of a steel sphere on a 7075-T6 hourglass specimen. The impacts occur at the minimum cross section, in the normal and oblique directions. The results reveal that in the event of an oblique impact the axial tensile stresses are greater and closer to the crater created by the impact. The superposition of the residual axial stresses to the bending stresses by fatigue test allows to identify the areas in which the maximum stresses are reached and therefore crack initiation is expected.
Fatigue behaviour assessment of C45 steel by means of energy-based methods
Authors: De Finis R , Palumbo D , Pirinu A , Saponaro A , Panella F W , Nobile R , Galietti U
Published: March 2021

Methods and techniques presented in literature for studying the fatigue behaviour of materials involve expensive, long lasting experimental campaigns and often a data analysis providing any information about damage localisation and occurrence. To avoid a time-consuming mechanical characterisation and to provide more information about where and when damage is occurring, the full-field experimental techniques such as infrared thermography allows the assessment of parameters that are related to the energy conversion to heat. In this work, the relationship between these thermal parameters (thermal methods) sentinels of the energy dissipated per cycle and the energy absorbed in every cycle is presented for the C45 steel undergoing stepwise loading fatigue tests.
Mechanical separation models for material recycling applications
Authors: Uggiosi D , Delogu M , Del Pero F , Berzi L
Published: March 2021

Mechanical recycling of common materials such as plastics requires appropriate material segregation, which is usually performed adopting processes similar to those developed for mineral engineering industry. Due to the need to increment amount and quality of selection products, such processes – still developed through trial-and-error approach – are also facing improvements in order to fit with the needs of different waste flows. The work here presented deals with methodologies for virtual and practical development of mechanical separation processes and, in particular, about the preliminary definition of densimetric tables devices; for this reason, a brief review on typical waste flow is provided. The case study considered is a mixed polymeric fragmented flow comprehending two main fraction (elastomer and rigid plastics), which have been subjected to a preliminary separation test. Due to the need to optimize the process, a model for material fluidization is proposed to investigate the relevance of process parameters (e.g. air speed value) depending on material bed characteristics. After this, an image processing tool for the rapid analysis of fragments has been prepared, its scope being to find out typical shape and size characteristics, needed as input to the model, and color identification and number, which can be used for output characterization and performance analysis. Model and image processing tool together constitute the basis for process redesign, optimization and verification.
Confidence intervals for the expected damage in random loadings: Application to measured time-history records from a Mountain-bike
Authors: Marques J M E
Published: March 2021

The fatigue damage of a structure is usually estimated by calculating the damage values of a limited number of measured random time-histories. The limited damage values are generally not identical due to the sampling variability. In a recent work, confidence interval expressions have been proposed to bound the expected damage value. The method revealed a good agreement with simulations, thus suggesting its use also with real measurements. The present paper investigates the above-mentioned confidence intervals for expected damage by a real engineering application, in which few measured time-history records, or even only one, are available. This goal is achieved after measuring the random loadings acting on an instrumented Mountain-bike riding in a typical north Italian off-road track. As the whole ensemble of an infinite number of time-histories is not available and the expected damage is thus not known a priori, a sort of calibrator sample damage value, which is computed using a large number of measured time-history records, is used to estimate the expected damage. The obtained results confirm the accuracy of the proposed approach also with real measurements.
CubeSat Spatial Expedition: An Overview From Design To Experimental Verification
Authors: Morettini G , Zucca G , Braccesi C , Cianetti F , Dionigi M
Published: March 2021

Over the past two decades, government space organizations have provided university-level inexpensive access to space that has prompted the design of miniaturized versions satellites for research scope: the ”CubeSats”. If on one hand, the standard specifications of this pico-satellite are widely defined to provide easy access to space for educational and research institutions, on the other hand, the design phases of the mechanical and electronic structures are however a very complex and delicate moment of fundamental importance for the success of the launch. The purpose of this document is to provide an exhaustive and critical picture, derived from a broad and in-depth literary analysis of all the critical phases to be faced in order to structurally verify a CubeSat 1U. Starting from the design phase, passing through the simulation and construction of the nano-satellite up to the effective execution of the experimental tests. The aim is to define a linear and efficient path underlining the possible errors and critical moments of the structural verification of a CubeSat.
An Experimental-Numerical Study on Curling Process for Metallic Caps Production
Authors: Bruno M , Bertocco A , Perrella M , Esposito L
Published: March 2021

In the field of food industry, adoption of metallic caps for the storage of agri-food products is widespread. This type of caps is obtained through a sequence of forming processes executed on a tinplate. First, the plane metal sheet is deep drawn to obtain a cup whose edge is slightly shaped inward, then a curling process forms the edge into a hollow ring. This paper is focused on the curling, which allows to assess the final cap shape immediately before the application of the cups on the jars. Since the process is generally made on packaging lines with high production rates, the design of a proper curling machine needs to consider the effect of fatigue as well as maximum load values. Because of the different cap dimensions and shapes contemporary worked on the line, the loads definition is not easy. The scope of this work is the development of a model for the prediction of curling loads for different cap shapes and sizes. The analytical solutions, available in literature, together with numerical simulations of the process were compared to experimental compression tests made on two different caps type. Considerations on caps geometry and size influence on curling force represent a contribution to the fitness for service evaluation as well as a starting point for the design of new curling machines.
Integration of nylon electrospun nanofibers into structural epoxy adhesive joints
Authors: Minosi S , Cocchi D , Pirondi A , Zucchelli A , Campanini F
Published: March 2021

The fracture toughness is a key parameter in the development of bonded joints for several structural applications. Adhesives are commonly toughened with fillers or modifying the resin chemical composition. Many studies also suggest that resin toughening could be achieved through electrospun polymer nanomat. In previous works, the Authors proved that nylon nanomats can be used as an adhesive carrier and reinforcing web for the adhesive layer. This allowed developing a laboratory route to produce high-quality prepregs of electrospun nylon carrier using medium viscosity, two-component, unfilled epoxy adhesive. By applying the same methodology, in the present work, electrospun nylon prepregs were produced using a high strength and high toughness 2k structural epoxy adhesive to toughen the joint. The wet nano-reinforced strips were placed between S235 steel sandblasted adherents and oven-cured to obtain Double Cantilever Beam (DCB) joints. DCB tests have been performed to compare the mode-I fracture toughness with and without the nanofibrous mat. Unlike previous works with medium-low toughness epoxies, this time the fracture toughness is reduced after the integration of an electrospun nano-reinforcement. From the Scanning Electron Microscope (SEM) images it seems that the nanomat hinders the ductile failure mechanism which instead develops in the neat resin.
Design of non-conventional biaxial tensile-shear tests for the structural characterization and ductile damage assessment of ductile engineering materials
Authors: Nalli F , Imbimbo B , Cortese L
Published: March 2021

The paper focuses on the development and optimization of a non-conventional specimen geometry for mechanical testing of ductile materials under shear-tension loading conditions. This is of major importance, being well known from literature works, that material final failure is strongly dependent on the stress state and that the information about the material ultimate resistance is crucial in virtually any kind of machine design related safety assessment. More in detail, in this study an effective way to load the samples with a combination of shear and tension is devised, selecting and optimizing a proper specimen geometry and designing the related gripping system. The goal is to obtain stress states in test runs different as much as possible one with the other, with specimens easy to be machined, and using just a standard universal testing machine. This would make the biaxial tests available to a broad group of end users, even industrial.

The state of the art of specimens for biaxial tests available in literature was used as starting point to design a novel simplified geometry and the dedicated gripping system. Numerical simulations of the prospective biaxial experiments were performed, ranging from pure shear to pure tension, to optimize the new geometry, improve its effectiveness and evaluate the material stress states and strain to fracture at the critical points that can be obtained from the tests. This local information proved to be sufficient to calibrate different damage models using the single proposed test, with proper combinations of shear to tension loads.
Different infill geometry influence on mechanical properties of FDM produced PLA
Authors: Bergonzi L , Vettori M , Stefanini L , D’Alcamo L
Published: March 2021

Fused Deposition Modelling (FDM) is one of the most widespread additive manufacturing technologies due to its relatively low cost and simplicity. Usually, printed parts have an internal structure (infill) that is not produced with 100% material density. This strategy is adopted to save material and time thanks also to the fact that when a component is loaded, stress are concentrated on its skin rather than in the internal section. Furthermore, infill structure can have different densities and topology. Slicer software have various configurations that can be exploited to produce internal structures: according to All3DP [1], some are intended for functional parts while others are more indicated to prototypes only. Aim of this work, is to compare the effect of different infill topologies produced using Ultimaker CURA [2] slicing software on material mechanical properties. Preliminary experimental activity has been carried out in order to determine the most suitable printing temperature. MaCh3D, an innovative miniaturized universal testing machine [3] was used to perform uniaxial tensile tests. Results underline the difference between different kind of infill in term of mechanical properties, given the same infill density across all specimens. Additionally, in order to evaluate infill percentage effect on mechanical properties, some of the most performing infill from the characterisation activity have been selected and specimens produced with 20%, 50%, 80% infill percentage. In the end, both infill topology as well as density impacts on mechanical properties.
Development and calibration of a structural simulation method of CF-SMC composite parts processed by compression molding
Authors: Delvò M , Nicoletto G , Riva E
Published: March 2021

The need for the reduction in CO2 production in automotive field increasingly leads manufacturers to consider fiber-reinforced composite materials that are however costly to processes. Discontinuous fiber composite materials, like CF - SMC, are a competitive candidate because they are transformed by the high productivity compression molding technology. On the negative side, their structural complexity introduces high variability in the mechanical performance that needs to be considered at the design stage. This contribution describes the development of a structural modeling strategy for parts made of CF-SMC processed by compression molding. It is based the statistical material model proposed by Feraboli implemented here in a FEA-based structural analysis procedure. After validation and calibration of a specific CF-SMC material, the proposed procedure is applied to the simulation of the structural response of a compression molded part of complex geometry subjected to know loading conditions.
Preliminary design and structural assessment of DTT in-vessel coil supports
Authors: Belardi V G , Calabrò G , Fanelli P , Giorgetti F , Lombroni R , Ramogida G , Trupiano S , Vivio F
Published: March 2021

The present work regards the design methodologies for a crucial component of the new thermonuclear fusion energy machine named “Divertor Tokamak Test facility” (DTT). The purpose of this experimental facility is the investigation of the thermal exhaust issue, a critical aspect in the view of DEMO construction, and future nuclear fusion reactors for commercial use. The construction of DTT machine is starting in the ENEA Site, Frascati, Italy. The poloidal magnet system in the proposed DTT includes a central solenoid divided into 6 independent modules, plus 6 external coils. The poloidal field system also includes six copper in-vessel coils, namely two in-vessel coils for radial and vertical plasma stabilization and control, and four out of six in-vessel divertor coils for magnetic control of scrape-off layer and strike point sweeping. This work aims to provide a preliminary design of the supports for the 6 in-vessel coils considering the Electromagnetic (EM) loads due to a plasma Downward (DW) Vertical Displacement Event (VDE) at the flat-top of plasma reference single null scenario. During a DW VDE a huge amount of current flows in the in-vessel coils (circumferential direction), whose interaction with the poloidal EM field generates strong EM forces. The electromagnetic loads have been calculated with MAXFEA, a two-dimensional finite elements code for the simulation of plasma equilibrium, and then applied to homogenized in-vessel coils in the structural analysis.
Meteorites ruled out as source of magnetized lunar crust
Authors: Jarman Sam
Published: March 2021

A leading theory as to why regions of the Moon’s crust are magnetized has been debunked by researchers led by Rona Oran at the Massachusetts Institute of Technology
A year (mostly) to forget
Authors: Durrani Matin
Published: March 2021

Physicists worldwide showed spirit and innovation, but 2020 can’t end soon enough
Science must listen to opposing views
Authors: Mehta Pruthvi
Published: March 2021

Pruthvi Mehta says that the ongoing controversy over the Thirty Meter Telescope continues to stain the field of astronomy
Over a century
Authors: McDowell Alex
Published: March 2021

In response to Amar S Bhalla and Avadh Saxena’s feature article “Ferroelectricity: 100 years on” (November pp38–41), which looks back at the discovery of the phenomenon, made a century ago by a PhD student called Joseph Valasek.
A nuclear maverick
Authors: Wright Peter
Published: March 2021

I was recently asked by my historian son for my view of the scientist Galen Winsor
Ambassador for the Space Age
Authors: Glester Andrew
Published: March 2021

Commercial spaceflight industry professional and science communicator Kellie Gerardi was one of the many who wanted to be part of the nascent Space Age. But with a degree in film studies rather than aerospace engineering, her nontraditional path in the space industry is a key theme of her new book Not Necessarily Rocket Science: a Beginner’s Guide to Life in the Space Age.
Characterization of normal and deformed red blood cells using simulated differential photoacoustic cross-section spectral data
Authors: Kaushik Anuj , Saha Ratan K
Published: March 2021

Frequency dependent differential photoacoustic cross-section (DPACS) over a large frequency band (100–1000 MHz) has been computed and subsequently, morphological parameters of photoacoustic (PA) source have been quantified. Green’s function method has been employed for computing the DPACS for a series of ellipsoidal droplets (with varying aspect ratio), Chebyshev particles (with different waviness (n) and deformation (ϵ) parameters), healthy red blood cell (RBC) and cells suffering from hereditary disorders (spherocytosis, elliptocytosis and stomatocytosis). The tri-axial ellipsoid form factor (TAEFF), finite cylinder form factor (CFF) and toroid form factor (TFF) models have been used to fit the DPACS spectrum to obtain size and shape information of the PA source. The TAEFF model estimates the shape parameters of the ellipsoidal droplets accurately (error < 5%). It is found that volume estimation is better (error < 10%) for lower order (n = 2, ϵ = ± 0.25) and very higher order (n = 35, 45, ϵ = ± 0.05) Chebyshev particles compared to those of n = 4, 6 and ϵ = ± 0.25. The TAEFF model predicts shape parameters of stomatocyte with volume error ≈15% but it is ≤6% for other cells. The opposite trend is observed for the CFF model. The TFF model is able to estimate the shape parameters efficiently for normal erythrocyte and stomatocyte but gives relatively large errors (>15%) for other deformed RBCs. The inverse problem framework may motivate to develop a PA-based technology to assess single cell morphology.
Accelerating the development of new solar absorbers by photoemission characterization coupled with density functional theory
Authors: Veal Tim D , Scanlon David O , Kostecki Robert , Arca Elisabetta
Published: March 2021

The expectation to progress towards Terawatts production by solar technologies requires continuous development of new materials to improve efficiency and lower the cost of devices beyond what is currently available at industrial level. At the same time, the turnaround time to make the investment worthwhile is progressively shrinking. Whereas traditional absorbers have developed in a timeframe spanning decades, there is an expectation that emerging materials will be converted into industrially relevant reality in a much shorter timeframe. Thus, it becomes necessary to develop new approaches and techniques that could accelerate decision-making steps on whether further research on a material is worth pursuing or not. In this review, we will provide an overview of the photoemission characterization methods and theoretical approaches that have been developed in the past decades to accelerate the transfer of emerging solar absorbers into efficient devices.