bluuebunny/crossref_metadata_2025 huggingface dataset:
Aplicación de la fotogrametría con drones al control deformacional de estructuras y terreno
Authors: Sancho Gómez-Zurdo Rubén , Galán Martín David , González-Rodrigo Beatriz , Marchamalo Sacristán Miguel , Martínez Marín Rubén
Published: April 2021

En este trabajo se estudia la viabilidad del empleo de drones para el control de deformaciones del terreno y las estructuras, analizando para cada caso, la resolución, precisión y validación con otras técnicas. Se presenta con detalle la técnica fotogramétrica Structure From Motion, empleada para elaborar ortofotografías y modelos 3D precisos sin necesidad de conocer previamente las posiciones y ángulos de incidencia. El uso de puntos de control precisos, así como drones con sistema integrado RTK, son factores relevantes para la obtención de resultados con alta precisión. Se presenta el caso de estudio de la monitorización de una gran estructura, en este caso una presa arco-gravedad. Los resultados obtenidos presentan una precisión en deformaciones de ±2 mm para la estructura. Esto confirma que la fotogrametría dron es aplicable al control deformacional de presas de hormigón, abriendo las posibilidades a la monitorización de otras grandes estructuras e infraestructuras.
Redes familiares cuidando a personas mayores dependientes: influencia del empleo y del estado civil de los hijos y las hijas
Authors: López Doblas Juan , Faus Bertomeu Aina , Gómez Redondo Rosa
Published: April 2021

Nuestro estudio aborda el cuidado que sus hijos o hijas proveen a las personas mayores, tomando como unidad de análisis a las redes de apoyo en que se enmarcan. El objetivo es doble: indagar en sus estrategias para compaginar esa dedicación con el empleo y en cómo las circunstancias laborales y familiares de cada cual condicionan su participación en el cuidado. En su desarrollo usamos una metodología cualitativa, en concreto entrevistas semiestructuradas para obtener información y teoría fundamentada para analizarla. Los resultados demuestran que, aunque la responsabilidad sea compartida, el estatus laboral de los y las hermanas determina su contribución al cuidado parental. También recogen estrategias comunes para compaginar empleo y cuidado, como el sacrificio de la carrera profesional o la búsqueda de apoyo externo a la familia, así como el rol protagonista que suelen asumir quienes se encuentran en situación de soltería. Dentro de las redes mixtas, además, constatamos que siguen existiendo diferencias de género.
EANNMHO – A Novel Ensemble Based Technique for Liver Cirrhosis Detection
Authors: M.R Vinutha , J Chandrika
Published: April 2021

In today's fast moving world, Liver Cirrhosis is considered as an aspect having substantial significance both at the national level and international level. The preliminary interest of medical science is to develop a constructive method to predict the Liver Cirrhosis at an early stage. The extreme heterogeneous nature of the disease along with non-standardized treatment makes its management a complex issue. Though medical modalities assess the disease, patients responses creates variation in them. Machine Learning techniques have been used in medical prognosis as it helps physicians to assess the disease faster. Taking this hint and contemplating the troubles faced by the physicians in diagnosing Liver Cirrhosis we have proposed a novel technique called EANNMHO.EANNMHO is a hybrid technique involving EANN-Ensemble Artificial Neural Network and MHO- Modified Harris Hawk Optimization and initially missing values are imputed using K-Nearest Neighbor. The Proposed model when evaluated against other ML techniques produces conclusive results.
Validation of An Instrument to Know the Use of Smart Devices in Air Conditioners and Their Improvement in Energy Efficiency: Case Study in Ecuador
Authors: Anchundia-Santana Jorge Israel , Sánchez-Cano Julieta Evangelina , Garcia-Quilachamin Washington , Santana-Mantuano Evelyn Isabel
Published: April 2021

The constant growth of the world’s population has generated various changes in the use of the diversity of the resources provided to us by the planet. Considering that by properly managing energy in air conditioning systems correctly, it collaborates in the fight against climate change, reducing the excessive use of fossil fuels and, therefore, the emission of CO2 and other greenhouse gases, creating an environment of comfort in industrial sectors, businesses, companies, homes, among others. The objective of this research is to validate the instrument considering the information obtained about smart devices applied in air conditioning systems and their improvement in energy efficiency. The methodology applied consisted of a field study conducted through an online survey that was directed at 226 students and professionals from three provinces of the Republic of Ecuador. To validate the data obtained in the instrument, the exploratory factor analysis was performed also of the principal components in the last phase it was obtained in factor transformation matrix (0.986), which demonstrates the validity of the study. To apply the KMO test and Bartlett’s sphericity, the following ranges (≥0.6) y (<0.05) were considered respectively.
Developing Medical Virtual Teaching Assistant Based on Speech Recognition Technology
Authors: Purbohadi Dwijoko , Afriani Silvia , Rachmanio Nicko , Dewi Arlina
Published: April 2021

This paper proposes to present the results of the development of the Virtual Teaching Assistant (VTA). This system is an e-learning module as a learning aid for medical students currently pursuing professional medical doctor in hospitals. In Indonesia, students of the medical doctor profession education must study and work in hospitals like an experienced doctor. They interact directly with patients and provide the same services as doctors. Every student has a professional doctor at the hospital as a mentor or companion. However, student meetings with accompanying doctors are minimal. It is not uncommon for students to encounter difficulties when dealing with patients, but they do not immediately receive guidance. As students, it is natural that they sometimes forget the theory. These students need a theoretical learning source that is fast and practical, which students can use between activities. We developed VTA to meet the needs of information and fast learning resources. VTA can run on computer, laptop, or smartphones by utilizing speech recognition technology. Students only need to ask questions in the form of speech using their everyday language, and VTA will provide answers. Although the VTA answer is still not satisfactory, it potentially to support Question and Answer-based mobile learning for particularly learning subject.
Validation Method on Determination of Chemical Oxygen Demand Using Indirect UV-Vis Spectrometry
Authors: Rohyami Yuli , Aprianto Toni , Marjono
Published: April 2021

The validation method for determination of chemical oxygen demand (COD) with indirect UV-Vis spectrometry have been done. This method enable to easily perform highly sensitive, considerably faster and easier, and minimize the use of digestion solution. This method is the development of standard method of COD determination by closed reflux using UV-Vis spectrometry so it requires the method validation stage. The validation is used to ensure linearity, limit of detection, limit of quantification, precision, and accuracy values in accordance with quality control. This study was also carried out to formulate the uncertainty calculation modeling of COD on water analysis. The result of validation method show that the calibration curve linearity is 0.9994 with the linear regression equation Y = 0.0003X + 0.0005. The method is able to have high sensitivity in measuring COD value with low concentrations with limit of detection and limit of quantitation of 9.78 and 32.59 mg O2/L. Indirect UV-Vis spectrometry has high precision with relative standard deviation of 0.66% and high accuracy with the percentage of recovery of 91.35%. The uncertainty formulation model on determination of COD from the source of standard uncertainty of sample volume, calibration curves, and repeatability.
Ethanol Extract Combinations Effect of Celery Herb (Apium graveolens L.) and Bay Leaf (Syzygium polyanthum W.) Toward Hypertensive Mice Induced by Sodium Chloride and High Fat Feed
Authors: Bachri Moch. Saiful , Putranti Widyasari , Widiyastuti Lina , Devie Resalianti Sintiana
Published: April 2021

The combination of herb medicine is alternative option in hypertension because it has more potential for treatment with complications like hyperlipida. Plant which can be used for anti-hypertension therapy is combination of celery herb (Apium graveolens) and bay leaf ethanol extract (Syzygium polyanthum). This research aims to determine the activity of a combination of celery herb ethanol extract (CHEE) and bay leaf ethanol extract (BLEE) and find out how much the decrease of blood pressure on the combination of both toward hypertension with high fat Wistar mice. The design of this research used an experimental design with pre-post control group design. Hypertensive mice are induced with high fat feed and orally with sodium chloride 8%, then the mice are supplied with combinations extract with the dose of 1.125 ; 6.25 ; 2.25 ; 12.5 and 4.5 ; 25 mg/kg, hydrochlorotiazide 2.25 mg/kg, Simvastatin 0.9 mg/kg, CHEE 4.5 mg/kg, BLEE 25 mg/kg and CMC-Na 0.5%. Research result shows that the combination can decrease systole blood pressure in the 22nd day. The extract combination has anti-hypertension effect (it is able to decrease systole blood pressure ≥ 20 mmHg) and it is not significantly different with normal group (p<0.05). Based on the research, it can be concluded that ethanol extract combination can decrease systole blood pressure with high fat complications after using it for 22 days.
A Preliminary Study for Modification of Wetting Properties on Cotton Polyester (TC) Fabric Surface Using Atmospheric Plasma Corona Discharge Technology
Authors: Putra Valentinus Galih Vidia , Mohamad Juliany Ningsih
Published: April 2021

Textile materials generally have intrinsic properties, such as flexibility, light volume density, strength, tenacity, comfort and softness. Based on these characteristics, the textile material is generally given a special additional function, such as hydrophobic or hydrophilic properties. The addition of these special functions to the textile industry is generally using conventional wet methods that require more energy and water as well as more chemicals need and expensive price. Plasma technology is one of the dry process technologies and it can reduce the use of chemicals that can pollute the environment. This article describes the application of atmospheric plasma corona discharge technology in the textile sector, especially its use in modifying wetting properties on the surface of polyester cotton (TC) 70%. The results showed that by varying the time of plasma treatment on 70% TC cotton polyester fabric with density of weft and warp respectively 70 strands / inch and 60 strands / inch we found that there was a change in the wetting properties of the fabric with increasing hydrophilic properties of the fabric. SEM images show the example of morphology of cotton polyester fabric surfaces treated with time of exposure by plasma at one minute (60 s) at 3 kV of output voltage as the optimal exposure time and applied voltage to enhance the wetting properties.
Biochar from Oil Palm Frond to Reduce Fe Ions in Artificial Solution and Peat Water
Authors: Yasdi Yasdi , Rinaldi Rinaldi , Anggraini Febri Juita , Yulianti Tiara
Published: April 2021

Raw oil palm fronds (OPF-R) converted into biochar (OPF-B) by torrefaction processes at temperatures range of 200 °C to 300 °C. This study aims to evaluate OPF-B performance to reduce iron ions in artificial solutions and peat water. Batch adsorption carried out at room temperature by stirring (175 rpm) using an orbital shaker. Some parameters observed included optimum torrefaction temperature, optimum conditions of Fe ions adsorption (optimum pH and contact time) and sorption isotherm. Metal content measured using atomic absorption spectroscopy (AAS). Functional groups on material surface characterized using Fourier Transform Infrared (FT-IR). Torrefaction at 260 °C produces biochar with the highest efficiency in removing iron ions. Both functional groups C=O and C-O attributed to lignocellulose on OPF-B were diminished and absorption band of aromatic (C=C) increased which caused by torrefaction. The optimum conditions for removal of Fe ions at pH 5 and 30 minutes contact time. Adsorption process follows the Langmuir Isotherm which indicates the formation of a monolayer with qmax 111.11 mg/g. Amount of 0.025 g OPF-B able to reduce iron concentration from 13.960 mg/L to 0.746 mg/L in 100 mL peat water (has complied with Indonesian clean water standard for iron concentration).
Enhancement of EAPR Treatment Using Double Aeration System and Uptake by Pakcoy (Brassica rapa subsp. chinensis)
Authors: Putra Rudy Syah , Sarkawi Muhammad , Ramadhani Aditya Deska , Sophiar Septianti Putri
Published: April 2021

This study was aimed at investigating the effect of electro-assisted and double aeration (EAPR-DA) system to enhance the lead removal in water and uptake by Pakcoy (Brassica rapa subsp. Chinensis). Variable regimes were created by 2 V of constant DC voltage using 2D stainless steel cathode-pot and Ti anode electrode, and aeration level of 10 L/min. The effectiveness of EAPR-DA, EAPR, phyto-aeration, and phytoremediation on the treatment was compared and evaluated by measuring the decrease of lead concentration in the water and accumulated in the plant using flame Atomic Absorption Spectroscopy. Plant stress was evaluated by phytomorphology changed and measurement chlorophyll content using UV-Vis Spectroscopy after the acetone extraction. The results showed that the EAPR-DA system using Pakcoy has a great ability to decrease the lead concentration in water compared with the EAPR, phyto-aeration, and phytoremediation. The removal ability in each reactor was 82.5%, 78.75%, 72.5%, and 61.875% respectively for EAPR-DA, EAPR, phytoremediation. and phyto-aeration. Excessive aeration in the root zone might inhibit lead adsorption by a plant in the phyto-aeration system. In general, the accumulation of lead in plant growth hydroponically has a large concentration in the roots compared to the shoot except for the EAPR-DA system which high adsorption of lead concentration in the shoot part. The BC (1.13) and TF (1.97) value of the EAPR-DA system was higher than the other systems, showing aeration can enhance high adsorption of lead in the root and then transported it into the shoots part. High chlorophyll total (54.89±14.31 mg/mL) and low chlorophyll a/b ratio (1.21±0.38) in the plant under the EAPR-DA system showed that the double aeration in the electro-assisted system encourages the high tolerance of the plant to the lead concentration.
Impact of Thermal Stratification on Unsteady Natural Convection Couette Flow Formation in a Vertical Channel Filled with Anisotropic Porous Material
Authors: Jha Basant Kumar , Musa Muhammad Kabir , Ajibade Abiodun O.
Published: April 2021

Recently, heat transfer problems where anisotropic porous medium or stably stratified fluid are taken into account have been separately studied. Developing a mathematical model that combines these physical quantities naturally results to complex coupled differential equations. In this paper, a fully developed time dependent natural convection Couette flow of stably stratified fluid between vertical parallel channels filled with anisotropic porous material is investigated. The governing partial differential equations are transformed into ordinary differential equations using Laplace transform techniques and then decoupled using D’Alembert method. Exact solutions in Laplace domain for the velocity and temperature equations are then obtained. A numerical method: Riemann-sum approximation is then used to invert the expressions for the velocity and temperature profiles, as well as the resulting skin friction, rate of heat transfer and volumetric mass flow rate into their corresponding time domain. The research establishes that both the anisotropic and the stratification parameters aid in regulating the fluid temperature and velocity. The research further reveals that the fluid velocity attains its maximum (or minimum) velocity when θ = 900 (or θ = 00) for k*<1 and when k*>1, the fluid velocity is least (or maximum) when θ = 900 (or θ = 00).
Investigating Thermal Stability in a Two-Step Convective Radiating Cylindrical Pipe
Authors: Lebelo Ramoshweu Solomon , Mahlobo Radley Kebarapetse , Adesanya Samuel Olumide
Published: April 2021

Thermal stability in a stockpile of reactive materials is analyzed in this article. The combustion process is modelled in a long cylindrical pipe that is assumed to lose heat to the surrounding environment by convection and radiation. The study of effects of different kinetic parameters embedded on the governing differential equation, makes it easier to investigate the complicated combustion process. The combustion process results with nonlinear molecular interactions and as a result it is not easy to solve the differential equation exactly, and therefore the numerical approach by using the Finite Difference Method (FDM) is applied. The numerical solutions are depicted graphically for each parameter’s effect on the temperature of the system. In general, the results indicate that kinetic parameters like the reaction rate promote the exothermic chemical reaction process by increasing the temperature profiles, whilst kinetic parameters such as the order of the reaction show the tendency to retard the combustion process by lowering the temperature of the system.
Frictional Heat Simulation of Brake Composites in a Pin-on-Disc Tribotesting
Authors: Yusubov Fikrat Fakhraddin
Published: April 2021

This paper presents the comparative investigation of temperature distributions in the pin-on-disc tribo-contact with dry friction conditions. Heat generation and distribution mechanism in contact of a pin made by phenolic resin–based brake friction composite and 35HNL steel disc counter-face material were studied. Both experimental and simulation methods were used to study the temperature changes. In order to analyse the thermal effects, the change in the coefficient of friction with time were also characterized. Experimental friction tests performed on universal “pin-on-disc"-type friction and wear test machine model MMW-1. Interface temperature measurements of the disc was conducted non-contact type infra-red laser thermometer. Heat simulations were modelled via finite element method using COMSOL Multiphysics 5.5, Heat Transfer in Solid Module. The simulations helped to determine in the increase of temperature over selected time period. Obtained experimental results compared with results of numerical analysis.
Beware the Tyranny, Resulted by Impact Factor Mania Among the Scientists: A Critical Review
Authors: Jayasundara C. C.
Published: April 2021

Publishing articles in high-ranked journals brings a higher payoff that designates a greater likelihood of scholastic success of academics and researchers. In the present climate, it provides many opportunities for researchers to be in a "Golden Club" and catch a great deal of offers from Head-hunters, particularly for jobs, research grants, and consultancies, as many people in the research/academic industry still rely on the fact that greater impact is widely apparent in high ranked journals and the journals with high Impact Factor (IF). In universities, many researchers in academic administration positions, who have already progressed with high visibility by publishing research in journals with high IF, always attempt to put into action the same level of requirements and stipulations in publications for tenure decisions of academic and research staff together with rewarding and endowing perks including financial incentives. Assessing junior colleagues purely by exercising the IF score or journal ranks in senior researchers' mind-set has been widely prevalent in academia in the global context. Enforcing rules and regulations for promotion, recruitment, and financial incentives for tenure decisions only for the publications in high profiled journals with top IF is a kind of mania. It, in turn, creates a dismantle discrimination and precede for academic bullying and professional prejudice in universities. Thus, this paper discusses some of the problems with IF and journal ranking mechanisms, which consist of prevailing distortions in the scientific industry by disclosing the failures to predict the definite impact and creation of perverse incentives.  It further proposes some points to be taken for reforming/devising an appropriate mechanism targeting the definite impact of essential scientific values of research and researchers that can be readily used for measuring the impact.
Effects of fertilization levels on growth performance of micro-propagated Cryptocoryne wendtii (Water Trumpet)
Authors: Harshani W. M. S. , Pahalawattaarachchi V. , Radampola K. , Herath S. S.
Published: April 2021

This study was conducted to evaluate the effects of different fertilization levels on growth performance of micro propagated water trumpet, Cryptocoryne wendtii to find the most suitable hardening medium. Micro-propagated ninety-six individual plants potted in the commonly used substrate of coir particles were used for the experiment and subjected to different fertilization levels of Albert’s solution. Plants were potted just after being taken from the vessels and eight plant pots kept in the tanks (25.5 L water) containing 0.5 gL–1, 1.0 gL–1, and 2.0 gL–1 of Albert’s solution, and fertilizer was not added into the control. Each treatment and control had three replicates and the experiment was conducted for nine weeks under natural light and temperature conditions. At the end of the experiment, plant growth performance in terms of plant height, root height, number of leaves etc. and water quality parameters were compared in One Way Analysis of Variance using SPSS (16.0). The electrical conductivity (EC) of the 0, 0.5, 1.0, 2.0 gL–1 treatments were 0.075, 0.75, 1.5, 3.0 µS/m, respectively. At the end of the experiment, plants grown in 0.5 gL–1 showed the best growth performance giving significantly highest plant height (11.77 ± 0.40 cm), root height (5.77 ± 0.03 cm), number of leaves (10.0 ± 0.3), number of roots (8.3 ± 0.3), wet weight of whole plant (0.3180 ± 0.0200 g), dry weight of whole plant (0.0206 ± 0.0003 g) and the largest leaf area (2.54 ± 0.01 cm2) in compared to other two treatments and control. In contrast, the uptake of Albert’s solution significantly increased with the increasing EC level. The results of this study revealed that, 0.5 gL–1 Albert’s solution is the most suitable fertilization level among tested three fertilization levels for the hardening process of micro-propagated C. wendtii.
Predictive factors for identifying macrolide responder in treating chronic rhinosinusitis
Authors: Seresirikachorn K. , Kerr S.J. , Aeumjaturapat S. , Chusakul S. , Kanjanaumporn J. , Wongpiyabovorn J. , Snidvongs K.
Published: April 2021

BACKGROUND: Low-dose macrolides (LDM) are anti-inflammatory agents with antineutrophilic activity, but patient selection for LDM therapy in treating chronic rhinosinusitis (CRS) is controversial. This study aimed to assess factors which predict LDM responders. METHODOLOGY: A prospective cohort study was performed. Patients with CRS received roxithromycin (150 mg) once daily for 12 weeks. Nasal secretions and serology were collected. Nine predictors for LDM response were assessed: nasal secretion IgE, nasal secretion IL-5, serum IgE, serum eosinophils, serum neutrophils, nasal polyps, asthma, allergy, and aspirin hypersensitivity, using receiver-operating curve analysis and multivariable logistic regression. Macrolide responders were those with sino-nasal outcome test-22 improvement, symptoms visual analogue scale decreased to ≤5, and no rescue medication. RESULTS: One hundred CRS patients (mean age 47.4±14.1 years, 45% male) were enrolled. Univariable logistic regression showed local total IgE less than 5.21; and serum eosinophils less than 2.2% associated with macrolide response. Multivariate models showed local total IgE maintained an independent association with macrolide response, with an ability to discriminate between responders and non-responders of 63%. Serum total IgE, nasal secretion IL-5, serum neutrophil, nasal polyp, asthma, allergy, and aspirin hypersensitivity showed no association with LDM response. CONCLUSIONS: Low total IgE level in the nasal secretion but not in the serum, predict LDM response.
3D-3D Self-Calibration of Sensors Using Point Cloud Data
Authors: Ravindranath Pradeep Anand , Buyukburc Kutluhan , Hasnain Ali
Published: April 2021

Self-calibration of sensors has become highly essential in the era of self-driving cars. Reducing the sensors’ errors increases the reliability of the decisions made by the autonomous systems. Various methods are currently under investigation but the traditional methods still prevail which maintain a strong dependency on human experts and expensive equipment that consume significant amounts of labor and time. Recently, various calibration techniques proposed for extrinsic calibration for Autonomous Vehicles (AVs) mostly rely on the camera 2D images and depth map to calibrate the 3D LiDAR points. While most methods work with the whole frame, some methods use the objects in the frame to perform the calibration. To the best of our knowledge, majority of these self-calibration methods rely on using actual or falsified ground truth values.

We propose a 3D-3D point cloud based continuous self-calibration approach that uses one or many objects identified in the sensor frames to cross-calibrate sensors without any reliance on initial calibration parameters or ground truth values. Considering the fact that multiple sensors have multiple views of the same scene, the common features or objects within the scene can be used to calibrate one sensor node with respect to the other. Our approach relies on point cloud data (PCD) generated from at least two sensors to cross-calibrate the mis-calibrated sensor with respect to the calibrated sensor. In this paper, we demonstrate that we can apply the method either by extracting the essential feature points of the object PCD (i.e., centroids of the objects) or the whole object PCD. Following which we optimize the cost function to obtain the extrinsic calibration parameters. Our method handles the problem of pose correction similar to calibration without any ground truth value from sensors just by using multiple consecutive frames. In comparison to other methods, our method performs calibration with low margins of errors in rotation and translation. This method has been tested on the publicly available KITTI dataset, which is widely used to assess various problems (object detection, segmentation, tracking, depth prediction etc.) related to self-driving cars. The simplicity of the method lets us do on-the-fly calibration of sensors with a high level of accuracy.
A Visual-Vestibular Model to Predict Motion Sickness Response in Passengers of Autonomous Vehicles
Authors: Jalgaonkar Nishant , Sousa Schulman Daniel , Ojha Sneha , Awtar Shorya
Published: April 2021

Multiple models to estimate motion sickness (MS) have been proposed in the literature; however, few capture the influence of visual cues, limiting the models’ ability to predict MS that closely matches experimental MS data. This is especially significant in the presence of conflicts between visual and vestibular sensory signals. This paper provides an analysis of the gaps within existing MS estimation models and addresses these gaps by proposing the visual-vestibular motion sickness (VVMS) model. In this paper, the structure of the VVMS model, associated model parameters, and mathematical and physiological justification for selecting these parameters are presented. The VVMS model integrates vestibular sensory dynamics, visual motion perception, and visual-vestibular cue conflict to determine the conflict between the sensed and true vertical orientation of the passenger. The model performance is verified by comparing MS response output against experimentally determined motion sickness measures from past investigations.
Zero-Day Attack Defenses and Test Framework for Connected Mobility ECUs
Authors: Kashani Ameer , Iyer Gopalakrishnan , Mora-Golding Carlos , Yamashita Hirofumi , Takeuchi Remma
Published: April 2021

Recent developments in the commercialization of mobility services have brought unprecedented connectivity to the automotive sector. While the adoption of connected features provides significant benefits to vehicle owners, adversaries may leverage zero-day attacks to target the expanded attack surface and make unauthorized access to sensitive data. Protecting new generations of automotive controllers against malicious intrusions requires solutions that do not depend on conventional countermeasures, which often fall short when pitted against sophisticated exploitation attempts. In this paper, we describe some of the latent risks in current automotive systems along with a well-engineered multi-layer defense strategy. Further, we introduce a novel and comprehensive attack and performance test framework which considers state-of-the-art memory corruption attacks, countermeasures and evaluation methods. Finally, we demonstrate the ability to deter and prevent in-field zero-day attacks on connected vehicle ECUs.
Electro-Thermal Control on Power Electronic Converters: A Finite Control Set Model Predictive Control Approach
Authors: Ozkan Gokhan , Hoang Phuong , Badr Payam , Edrington Christopher
Published: April 2021

With the increasing attention towards electric vehicles (EV), power electronics technology has become more prominent on vehicular systems. EV requires compact energy conversion and control technology to improve system efficiency and optimize the sizing of power components. Therefore, it is important to reduce thermal losses, while supplying an adequate amount of power to different EV devices. Silicon carbide (SiC)-based power semiconductors provide performance improvements such as lower power losses, higher junction temperature and higher switching frequency compared to the conventional silicon (Si)-based switching devices. High-frequency switching is preferred for power converters to minimize the necessity of passive filters; however, high-frequency switching causes additional thermal stress on semiconductor switches due to the increase in switching losses. The degradation of switching devices in power converters are primarily related to the junction temperature. One method to improve the lifetime of semiconductors is to control the module junction temperature by controlling switching losses in the switching state, while providing power quality in the required limits and maintaining voltage stability. This concept is referred to as active thermal management. This paper illustrates the Finite Control Set Model Predictive Control (FCS-MPC) approach on how electrical performance can be preserved while providing electro-thermal management for the SiC-based switching devices on three-level three-phase power converter to improve system efficiency and reliability.
COVID Killing Air Purifier Based on UV & Titanium Dioxide Based Photocatalysis System
Authors: Mathur Gursaran
Published: April 2021

In a photocatalytic air purifier system, the catalyst that cleans the air is typically titanium dioxide and it is energized by ultraviolet (UV) light. When UV light shines on the titanium dioxide, electrons (negatively charged particles inside atoms) are released at its surface. The electrons interact with water molecules (H2O) in the air, breaking them up into hydroxyl radicals (OH·), 9which are highly reactive, short-lived, uncharged forms of hydroxide ions (OH−). These small, agile hydroxyl radicals then attack bigger organic (carbon-based like virus) pollutant molecules, breaking apart their chemical bonds and turning them into harmless substances such as carbon dioxide and water.

Current investigation uses the above principle to kill living organic germs, bacteria; pathogen, etc. from the cabin air in recirculation mode. A HVAC system has been developed by using a filter impregnated by titanium di-oxide (TiO2) with UV lights to improve and maintain cabin air quality. The developed system has been developed to kill virus, germs, pathogens and bacteria that typically exist in a conditioned space. The designed system can be used for conventional vehicles, EVs, ride sharing and for autonomous vehicles. Tests were conducted at a certified laboratory with MS2, a bacteriophage size of 0.027 microns. MS2 is a proxy for SARS-CoV-2, the virus that causes COVID-19 with a size of 0.125 microns. Effectiveness of the destruction rate was determined for the developed system. Detailed summary will be presented in the paper.
Tanker Truck Rollover Avoidance Using Learning Reference Governor
Authors: Liu Kaiwen , Li Nan , Kolmanovsky Ilya , Rizzo Denise , Girard Anouck
Published: April 2021

Tanker trucks are commonly used for transporting liquid material including chemical and petroleum products. On the one hand, tanker trucks are susceptible to rollover accidents due to the high center of gravity when they are loaded and due to the liquid sloshing effects when the tank is partially filled. On the other hand, tanker truck rollover accidents are among the most dangerous vehicle crashes, frequently resulting in serious to fatal driver injuries and significant property damage, because the liquid cargo is often hazardous and flammable. Therefore, effective schemes for tanker truck rollover avoidance are highly desirable and can bring a considerable amount of societal benefit. Yet, the development of such schemes is challenging, as tanker trucks can operate in various environments and be affected by manufacturing variability, aging, degradation, etc. This paper considers the use of Learning Reference Governor (LRG) for tanker truck rollover avoidance. The LRG is an add-on scheme to a nominal closed-loop system (i.e., the tanker truck in this application). The LRG monitors the maneuver command from the driver (or from a higher-level planning algorithm in the case of an automated tanker truck) and adjusts it when necessary to enforce rollover constraints. One major novelty of this LRG scheme is that its formulation relies on learning, rather than explicit modeling of the system, where learning can be performed on a high-fidelity, black-box model of the truck system or through experimentation with the actual truck. We illustrate the effectiveness of this LRG-based rollover avoidance scheme through simulation studies corresponding to various truck operating conditions.
Automatic Formal Verification of SysML State Machine Diagrams for Vehicular Control Systems
Authors: Mahani Maziar , Rizzo Denise , Paredis Chris , Wang Yue
Published: April 2021

Vehicular control systems are characterized with numerous complex interactions with a steady rise of autonomous functions, which makes it more challenging for designers and safety engineers to identify unexpected failures. These systems tend to be highly integrated and exhibit features like concurrency for which traditional verification and validation techniques (i.e. testing and simulation) are insufficient to provide rigorous and complete assessment. Model Checking, a well-known formal verification technique, can be used to rigorously prove the correctness of such systems according to design Requirements. In particular, Model Checking is a method for formally verifying finite-state concurrent systems. Specifications about the system are expressed as temporal logic formulas, and efficient symbolic algorithms are used to traverse the model defined by the system and check if the specification holds or not. Systems Modeling Language (SysML) has been widely used in architectural and functional modeling in automotive industries. However, it cannot directly be verified against safety requirements. In this work, SysML is used to establish a unified system model that can present an integrated autonomy software and hardware system of a vehicular control system. A generic model transformation strategy is developed to integrate SysML with one of the state-of-the-art Model Checking tools, NuSMV. Cameo Systems Modeler is an industry leading cross-platform collaborative Model-Based Systems Engineering environment for designing standard-compliant SysML models and diagrams. A native Cameo's plugin is constructed to transform SysML state machines to the input language of NuSMV model checker and also to replay the verification results back into the Cameo's environment. A case study of an executable state machine for a high-level autonomous driving system is built. The NuSMV model checker is used to model check the state machine of the autonomous driving system against design requirements expressed as temporal logic formulas. Upon violation of design requirements, our SysML-NuSMV integration allows to replay counterexamples in the Cameo modeling environment. Thus a bi-directional integration of system modeling language with the model checker is developed and the transformation rules are defined. The case study result shows how this method can help designers and safety engineers to automatically identify hidden design errors in a variety of possible design models.
The Effect of Quench Parameters on Self-Piercing Rivet Joint Performance in a High Strength Automotive 6111 Aluminum Alloy
Authors: Freiberg Daniel , Ilinich Andrey , Huff Garret , Freis Amanda , Luckey S. George , Barbier David , Dodge Phil , Masse Jean-Philippe , Wang He Qin , Afseth Andreas
Published: April 2021

The process parameters to manufacture structural aluminum alloys are critical to their ductility. In particular, quench rate after solution heat treatment impacts the extent of grain boundary precipitation and the formation of precipitate free zone (PFZ) during later artificial aging. Cu-containing 6XXX alloys used for high strength automotive applications are quench sensitive as the Cu addition leads to Q-phase precipitation at grain boundaries, resulting in loss of ductility, which can negatively affect downstream manufacturing steps such as automotive joining and forming processes. Self-piercing rivet (SPR) joining, is a single step, spot joining process used to mechanically connect sheet materials together in automotive body structures. Ductility has been identified as an important metric of material rivet-ability or the ability to make a successful, crack-free SPR joint.

Through a full-scale industrial trial on a high strength 6111 aluminum alloy - varied quench rates ranging from slow to fast have been used to produce different grain boundary precipitation and PFZ characteristics. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize grain boundary precipitation and PFZ width as a function of quench rate. Multiple mechanical characterizations, including SPR joint evaluations were done as a function of quench rate. It is shown that uniform and total elongation metrics are not suitable to understand rivet-ability. Instead, ductility metrics from both bending and reduction of area measurements from tensile tests were found to correlate with SPR joint quality.
Review and Comparison of Different Multi-Channel Spatial-Phase Shift Algorithms of Electronic Speckle Pattern Interferometry
Authors: Zhang Boyang , Guo Bicheng , Zheng Xiaowan , Yang Lei , Yang Lianxiang
Published: April 2021

Electronic Speckle Pattern Interferometry (ESPI) is the most sensitive and accurate method for 3D deformation measurement in micro and sub micro-level. ESPI measures deformation by evaluating the phase difference of two recorded speckle interferograms under different loading conditions. By a spatial phase shift technique, ESPI allows for the rapid, accurate and continuous 3D deformation measurement. Multi-channel and carrier frequency are the two main methods of spatial phase shift. Compared with carrier frequency method, which is subject to the problem of spectrum aliasing, multi-channel method is more flexible in use. For extracting the phase value of speckles, four-step algorithm and five-step arbitrary phase algorithm are commonly used. Different algorithms have different spatial resolution, operational requirements, and phase image quality. In order to better understand the impact of different algorithms, we present a comparison of these methods of spatial phase measurement in terms of quality and operability. Besides, this paper also conducts experimental research and discussion on the relationship between speckle and corresponding pixels. Basic theory, brief derivation and optical layouts for the three algorithms will be presented. The potentials and limitations of the multi-channel spatial phase shift ESPI system will be demonstrated by examples of precise measurement of deformation.
Development of Unidirectional CFRP Reinforced Aluminum Bumper Reinforcement
Authors: Miura Masaya , Ishii Michiharu , Takaoka Kanji , Horibe Yasumasa , Kitakata Shintaro , Mikuni Atsushi
Published: April 2021

Since bumper reinforcements are positioned at front/rear ends of vehicles, weight reduction of the bumper reinforcements enhances vehicle dynamic performance by reducing a yaw moment of inertia. CFRP (Carbon Fiber Reinforced Plastic) composites are attractive lightweight materials due to their excellent specific strength and rigidity. However, because of their relatively high cost, applications of CFRP materials to vehicle structural parts are limited. In this study we have developed a lightweight, structural part, which consists of a thin-walled Al (Aluminum) bumper reinforcement with a UD (Unidirectional)-CFRP sheet. The intention is to prevent an increased part cost by reducing the amount of Al and by minimizing the amount of CFRP. Compared to Al, UD-CFRP sheets have even higher tensile strength and modulus. When vehicles crash, bumper reinforcements may be subjected to bending force. If a UD-CFRP sheet is adhered on the tensile side of an Al bumper reinforcement, not only Al thickness on the tensile side, but also thickness on the compression side can be reduced due to movement of the bending neutral axis. In this design with a multi-material structure, bending strength of the developed part can’t be predicted by a full plastic moment which could normally be used to predict metal parts’ bending strength under large deformation. We employed a novel cross-section design method which can be used to predict bending strength of CFRP reinforced metal structures under large deformation. To validate the calculation method, three-point bending tests on the parts were carried out. Experimental data of bending strength were in the range of predicted bounds. Also, in order to launch the developed part, robustness of part’s performance was evaluated. Finally, the part was adapted to the rear bumper reinforcement of LEXUS RC-F. The part weight is 11 % lighter compared to the conventional, all-Al, bumper reinforcement.
Composite Control Arm Design: A Comprehensive Workflow
Authors: Carello Massimiliana , de Carvalho Pinheiro Henrique , Messana Alessandro , Freedman Alexander , Ferraris Alessandro , Airale Andrea Giancarlo
Published: April 2021

This paper presents a complete overview of the computational design of an advanced suspension control arm constructed of composite material for light weighting purposes. The proposed methodology presented in detail is split into 3 phases. Phase 1 or Vehicle Performance Simulation, in which basic modelling and a sensibility study is performed to better understand the advantages of unsprung mass reduction (compared to sprung mass reduction) with respect to the vehicle’s vertical dynamics. It followed by the development and utilization of a multibody approach to evaluate the full-vehicle response to different dynamic maneuvers, such as harsh road imperfections, sine sweep steering, and double lane change tests. The impact of the improved suspension control arm is highlighted in detail, and the loads to which it is subjected are computed to serve as inputs for the successive phases. Phase 2 or Design and Calculation Phase, where a closer look is given to the structural side of the component, understanding the specific behavior of composite materials and performing modelling of the control arm, followed by fine tuning with Finite Element Method optimization techniques. This phase consists of a topology optimization, followed by composite topography free size, size, and shuffle optimizations to arrive upon the ideal part-layup, and guarantee the desired mechanical characteristics of the component. Lastly, Phase 3 or the Production Preparation closes the design process by generating the production processes, steps, constraints, and tooling for the correct realization of the innovative control arm in a real-world application. The tools presented in this paper were created to allow the design to be completed rapidly, thus defining a blueprint for a full workflow, from engineering request to product delivery, which can be applied to different vehicles and customer requests, representing an essential step forward to the consolidation of the use of composite materials for structural suspension components.
Designing a Production-Ready Ultra-Lightweight Carbon Fiber Reinforced Thermoplastic Composites Door
Authors: Mittal Ashir , Kothari Anmol , Pradeep Sai Aditya , Savla Sushil , Limaye Madhura , Li Gang , Pilla Srikanth , Swaminathan Pal , Yarlagadda Shridhar , Hahnlen Ryan , Detwiler Duane
Published: April 2021

Vehicle lightweighting has been a constant theme of research at numerous Original Equipment Manufacturers (OEM’s) as it provides one of the best opportunities for improving fuel efficiency. In this regard, the Department of Energy (DOE) Vehicle Technology Office set a challenge to lightweight a fully assembled driver’s side front door by at least 42.5% with the cost constraint of a maximum $5 increase for every pound saved. A baseline door of an OEM’s 2014 mid-size SUV was selected, and an integrated design, analysis, and optimization approach was implemented to meet this goal. The ultra-lightweight door design had to meet or exceed the fit & function and mechanical performance (static and dynamic) of the baseline door while being suitable for mass production. The design strategy involved parts consolidation, and multi-material distribution to enable mass reduction without compromising the fit and functional requirements. The primary structural component of this ultra-lightweight door design is a composite inner-frame made of a woven carbon/Nylon-6 composite material. While a finite element composite optimization technique was implemented to design the ultra-lightweight door that met the static and dynamic performance targets, it lacked manufacturing inputs. This study focuses on the feasibility of large-scale manufacturing of the composite inner-frame using thermoforming processes. One benefit of employing these processes is that the existing OEM stamping lines can be utilized with minor modifications with no additional capital cost for equipment. The scope of this paper is to identify the challenges in thermoforming of the thermoplastic door - including shear angle, tearing, and wrinkle formation - using draping simulation and share the solution in the form of countermeasures in the part design and tool concept to make the manufacturing of the final part feasible.