bluuebunny/crossref_metadata_2025 huggingface dataset:
Excitation of airwaves by bubble bursting in suspensions : regime transitions and implications for basaltic volcanic eruptions
Authors: Hashimoto Kana , Sumita Ikuro
Published: July 2021

Basaltic magma becomes more viscous, solid-like (elastic), and non-Newtonian (shear-thinning, non-zero yield stress) as its crystal content increases. However, the rheological effects on bubble bursting and airwave excitation are poorly understood. Here we conduct laboratory experiments to investigate these effects by injecting a bubble of volumeVinto a refractive index-matched suspension consisting of non-Brownian particles (volumetric fraction$$\phi$$ϕ) and a Newtonian liquid. We show that depending on$$\phi$$ϕandV, airwaves with diverse waveforms are excited, covering a frequency band of$$f = {\mathcal {O}}(10-10^4)$$f=O(10-104)Hz. In a suspension of$$\phi \le 0.3$$ϕ≤0.3or in a suspension of$$\phi = 0.4$$ϕ=0.4with aVsmaller than critical, the bubble bursts after it forms a hemispherical cap at the surface and excites a high-frequency (HF) wave ($$f \sim 1-2 \times 10^4$$f∼1-2×104Hz) with an irregular waveform, which likely originates from film vibration. However, in a suspension of$$\phi = 0.4$$ϕ=0.4and with aVlarger than critical, the bubble bursts as soon as it protrudes above the surface, and its aperture opens slowly, exciting Helmholtz resonance with$$f = {\mathcal {O}}(10^3)$$f=O(103)Hz. Superimposed on the waveform are an HF wave component excited upon bursting and a low-frequency ($$f = {\mathcal {O}}(10)$$f=O(10)Hz) air flow vented from the deflating bubble, which becomes dominant at a largeV. We interpret this transition as a result of the bubble film of a solid-like$$\phi = 0.4$$ϕ=0.4suspension, being stretched faster than the critical strain rate such that it bursts by brittle failure. When the Helmholtz resonance is excited by a bursting bubble in a suspension whose surface level is further below the conduit rim, an air column (lengthL) resonance is triggered. ForLlarger than critical, the air column resonance continues longer than the Helmholtz resonance because the decay rate of the former becomes less than that of the latter. The experiments suggest that a bubble bursting at basaltic volcanoes commonly excites HF wave by film vibration. The Helmholtz resonance is likely to be excited under a limited condition, but if detected, it may be used to track the change of magma rheology or bubbleV, where theVcan be estimated from its frequency and decay rate.
Pulmonary and intestinal microbiota dynamics during Gram-negative pneumonia-derived sepsis
Authors: Wolff Nora S. , Jacobs Max C. , Wiersinga W. Joost , Hugenholtz Floor
Published: July 2021

Background

The gut microbiome plays a protective role in the host defense against pneumonia. The composition of the lung microbiota has been shown to be predictive of clinical outcome in critically ill patients. However, the dynamics of the lung and gut microbiota composition over time during severe pneumonia remains ill defined. We used a mouse model of pneumonia-derived sepsis caused by Klebsiella pneumoniae in order to follow the pathogen burden as well as the composition of the lung, tongue and fecal microbiota from local infection towards systemic spread.

Results

Already at 6 h post-inoculation with K. pneumoniae, marked changes in the lung microbiota were seen. The alpha diversity of the lung microbiota did not change throughout the infection, whereas the beta diversity did. A shift between the prominent lung microbiota members of Streptococcus and Klebsiella was seen from 12 h onwards and was most pronounced at 18 h post-inoculation (PI) which was also reflected in the release of pro-inflammatory cytokines indicating severe pulmonary inflammation. Around 18 h PI, K. pneumoniae bacteremia was observed together with a systemic inflammatory response. The composition of the tongue microbiota was not affected during infection, even at 18–30 h PI when K. pneumoniae had become the dominant bacterium in the lung. Moreover, we observed differences in the gut microbiota during pulmonary infection. The gut microbiota contributed to the lung microbiota at 12 h PI, however, this decreased at a later stage of the infection.

Conclusions

At 18 h PI, K. pneumoniae was the dominant member in the lung microbiota. The lung microbiota profiles were significantly explained by the lung K. pneumoniae bacterial counts and Klebsiella and Streptococcus were correlating with the measured cytokine levels in the lung and/or blood. The oral microbiota in mice, however, was not influenced by the severity of murine pneumonia, whereas the gut microbiota was affected. This study is of significance for future studies investigating the role of the lung microbiota during pneumonia and sepsis.
Depression among attendants of the Sudanese National Association of the Blinds in Khartoum, Sudan
Authors: Shazali Rayan Hisham Salaheldin , Mohamed Sagad Omer Obeid
Published: July 2021

Background

Blindness has profound consequences for the victim, family, and society. The impact of vision loss on daily life activities could lead to psychological stress. Early treatment of depression may reduce the added disability that is associated with vision loss. This study aimed to assess the extent and associated factors with depression among the Sudanese blind people in Khartoum, Sudan. A cross-section facility-based study was conducted, in which depression among the participants was assessed using the Beck Depression Inventory Scale. A chi-square test was implemented to determine the relationship between categorical variables and the significance level for all analyses was set at p < 0.05.

Results

A total of 185 participants were included in the study. Out of them, 84.3% were male and near half of the participants (42.2%) were born blind. The prevalence of depression among the participants was 11.4%. There were significantly higher rates of depression in those who were illiterate (χ2 = 6.233, p = 0.044) and in those whose loss of vision was due to accidents or traumatic causes and loss of vision due to accidents or traumatic causes (χ2 = 12.840, p = 0.002). There was significantly lower rate of depression in those who were born with blindness compared to others (χ2 = 10.504, p = 0.005).

Conclusions

People who were born blind have a lower rate of depression and people who lost their sight due to trauma have a higher rate of depression, and therefore, requiring more psychiatric support. Despite the relatively low percentage of depression, establishing programs for early identification and combating depression among the blind population in our setting is highly recommended.
Affordable Care Act and Cancer Survivors' Financial Barriers to Care: Analysis of the National Health Interview Survey, 2009-2018
Authors: Su Christopher T. , Okullo Dolorence , Hingtgen Stephanie , Levine Deborah A. , Goold Susan D.
Published: July 2021

PURPOSE:

Since Affordable Care Act (ACA) implementation in 2014, studies have demonstrated gains in insurance coverage for cancer survivors < 65 years. We assessed the impact of ACA implementation on financial barriers to care by stratifying survivors at age 65 years, when individuals typically become Medicare-eligible.

METHODS:

We used data from respondents with cancer in the 2009-2018 National Health Interview Survey. We identified 21,954 respondents representing approximately 7.4 million survivors, who were then age-stratified at age 65 years. Survey responses regarding financial barriers to medical care and medications were analyzed, and age-stratified multivariable logistic regression modeling was performed, which evaluated the impact of ACA implementation on these measures, adjusted for demographic and socioeconomic variables.

RESULTS:

After multivariable logistic regression, ACA implementation was associated with higher adjusted odds of Medicaid insurance (odds ratio [95% CI] 2.02 [1.72 to 2.36]; P < .0001) and lower adjusted odds of no insurance (0.57 [0.48 to 0.68]; P < .0001). Regarding financial barriers, ACA implementation was associated with lower adjusted odds of inability to afford medications (0.68 [0.59 to 0.79]; P < .0001), inability to afford dental care (0.83 [0.73 to 0.94]; P = .004), and delaying care (0.78 [0.69 to 0.89]; P = .002) in the 18-64 years group. Similarly, ACA implementation was associated with lower adjusted odds of secondary outcomes such as delaying refills, skipping doses, and anxiety over medical bills. Similar associations were not seen in the > 65 years group.

CONCLUSION:

Survivor-reported measures of financial barriers in cancer survivors age 18-64 years significantly improved following ACA implementation. Similar changes were not seen in the Medicare-eligible cohort, likely because of high Medicare enrollment and few uninsured.
Fundamentals of Information Theory: a reference book
Authors: Maskaeva Aleksandra
Published: July 2021

The textbook contains theoretical, practical and control and measuring materials. It can be used by teachers for conducting classes in the disciplines "Fundamentals of the Theory of Computer Science" and "Computer Science", as well as by students for preparing for test papers, for testing and control works in these disciplines. It is also suitable for students studying in an inclusive form using distance technologies.
Meets the requirements of the federal state educational standards of secondary vocational education of the latest generation.
For students studying in the specialties of secondary vocational education 09.02.05 " Applied Informatics (by industry)" and 09.02.06 "Network and system Administration".
The dynasty of Sibiryak merchants and its role in the development of Eastern Siberia in the XVIII-early XX century
Authors: Dikun Aleksandr
Published: July 2021

The monograph highlights the main stages of the formation and development of the dynasty of Irkutsk merchants Sibiryakovs, the participation of its representatives in the life of the region in the context of modernization processes that took place in the country as a whole and in Siberia in particular. The multifaceted entrepreneurial, social, research and charitable activities of all generations of the Sibiryakovs in the Siberian region in the period from the XVIII to the XX century are considered within the framework of local history.
The author analyzes the structure of the dynasty, the order and rules of inheritance of property, the system of family ties, individual and group social and economic mobility, social functions of the sexes, socio-political and cultural representations, formal and informal means of influence within the family, the economic activity of the dynasty as a whole.
It is addressed to teachers, methodologists, students of historical faculties, everyone who is interested in the history of Siberia. The materials and main provisions of this research can be used in the preparation of educational and methodological manuals, for the development of special courses on the history of the region and the creation of generalizing works on the economic development of Siberia, programs on historical and local history, economic and cultural education, patriotic education of the younger generation.
Implementation of the constitutional rights and freedoms of man and citizen
Authors: Narutto Svetlana , Kolmakov Stanislav
Published: July 2021

The textbook is devoted to theoretical issues of legal regulation of the implementation of constitutional human rights and freedoms, legal mechanisms for their protection, the competence of public authorities that ensure the implementation of rights and freedoms.
For students, postgraduates, teachers interested in the issues of human rights activities of the state, the participation of authorities in ensuring the implementation of constitutional rights and freedoms of man and citizen.
Criminal proceedings
Authors: Proshlyakov Aleksey
Published: July 2021

The textbook was prepared by the author's team of the Department of Criminal Procedure of the Ural State Law University in accordance with the course program "Criminal Procedure" developed by him, which fully complies with the State Standard of higher legal education (bachelor's, specialist, master's, postgraduate).
It takes into account and uses all the changes made to the criminal procedure law, judicial practice, as well as a wide range of scientific and
practical works of domestic and foreign procedural scientists.
The textbook is provided with a glossary and illustrated with diagrams on the main topics of the course.
For students, postgraduates and teachers of law schools and faculties, as well as practicing lawyers, law enforcement officers, researchers
Publiczna i prywatna religijność królowej Marii Kazimiery
Authors: Skrzypietz Aleksandra
Published: July 2021

Public and Private Religiosity and Piety of the Queen Marie Casimire d’Arquien Sobieska
In the early modern period, queens were obliged to participate in religious ceremonies and outwardly display their piety through charity. Marie Casimire de la Grange d’Arquien Sobieska met these duties when she was consort of the King John III Sobieski, and later, as a widow residing in Rome. Yet, her prayers were not limited to outward gestures of religiosity at official ceremonies. From her numerous letters, we can learn about her personal piety. In her letters written to Jakub, her eldest son, and his wife, the queen mother often refers to God’s Providence, and expresses her deep devotion and faith in God’s grace and protection. For Queen Marie Casimire, God was the source of comfort in difficult moments. While her outward religiosity is a reflection of the age in which she lived, the queen’s personal faith developed over time and appears to have been deep and sincere.
How Do Anti-discrimination Laws Affect Firm Performance and Financial Policies? Evidence from the Post-World War II Period
Authors: Greene Daniel , Shenoy Jaideep
Published: July 2021

We exploit the staggered passage of state-level fair-employment laws in the post-World War II period to examine how stronger worker protection against racial discrimination affects firm profitability and financing decisions. We find that firms experience a decline in operating profitability after the passage of anti-discrimination laws. We also document that the adoption of these laws leads to a reduction in debt ratios, which suggests that firms are able to partially offset the negative effects on operating profitability by adjusting their capital structure. Consistent with theoretical predictions, these effects of anti-discrimination laws are more pronounced for firms in states and cities with a greater proportion of African Americans, firms with high labor intensity, firms in states experiencing high African American migration, and firms in concentrated industries. Some of our evidence suggests that anti-discrimination laws lead to a reduction in statistical discrimination or monopsony power rather than taste-based discrimination. Taken together, our results are supportive of theoretical models of discrimination and show that racial discrimination laws significantly affect firm operating performance and financial policies.

This paper was accepted by David Simchi-Levi, finance.
The aesthetic specialism
Authors: Bennett Sharon
Published: July 2021

Sharon Bennett provides feedback to the recently published 10-point plan from the Joint Council for Cosmetic Practitioners and details the ongoing events from the British Assocation of Cosmetic Nurses
Re-Infection by SARS-Cov-2 with in 5 Months: A Case Report
Authors: Gamez Luis Darío-Martínez- , Ibarra-Valencia Elva Adelina , Meza-Ledesma María Angélica , Flores-Vargas Gilberto , Navarro-Olivos Efraín , Gallardo-Luna María de Jesús , Raygoza Nicolás Padilla-
Published: July 2021

The first reinfection in the world in Hong Kong, later in Europe (Holland, Belgium) and USA, was documented. In Mexico until November 2020 there are no medical articles that tell us about reinfection; in Celaya Guanajuato the case of a female patient presented with symptoms of COVID-19, 2 polymerase chain reaction in real time tests are performed, in the Laboratory of Public Health from Guanajuato State in an interval of time, less than 5 months; the first in June 2020, with a positive result, received symptomatic treatment and isolation at home for 14 days, negative IgG antibodies test 38 days later; the second time, she presented clinical data on COVID-19 in November From 2020. It was not find references about re-infections by SARS-CoV-2 in Mexico; in Celaya Guanajuato was presented the case of female patient who has symptoms of COVID-19, with new positive PCR, required hospitalization and high-flow oxygen therapy when presenting with pneumonia, was performed simple chest Computing tomography, IgG and IgM antibodies.The evolution was good with discharge from hospitalization 72 hours after admission, continuing his outpatient management until discharge.
Pharmacovigilance Study of Anticancer Drugs in a Tertiary Care Rural Hospital in Central India
Authors: Chakraborty Dipankar , Kale Ranjana S , Das Lakshman , Das Mousumi , Kirde Sonali
Published: July 2021

The present study has been undertaken to evaluate the pattern of adverse drug reactions (ADRs) of intravenous anticancer (i.v.) drugs with their causality and severity in a tertiary health care set up. The study was an observational cross-sectional survey over a period of 18 months. The indoor patients who were diagnosed to have cancer and receiving i.v. anticancer drugs were included in the study. The details of the patients and ADRs were recorded at the time of visit or within one-month of occurrence of ADRs using case record form and ADR reporting form. A total of 374 patients on cancer chemotherapy were included in the study and ADR was seen in 293(78.34%) patients. Out of total 812 number of ADRs, most ADRs (51.60%) were G.I. system related, followed by skin and appendages related ADRs (23.88%). The association of females in developing haematological ADRs is statistically significant (p<0.05). Most common (19.80%) cause of ADRs was the use of combination of Cisplatin, Paclitaxel and 5 Fluorouracil. Most (90.02%) of the ADRs were categorized as ‘possible’ and the remaining (9.98%) as ‘probable/likely’. The maximum number of the ADRs were classified as ‘mild’(87.68%) followed by moderate (11.45%) and severe (0.86%). The mild reactions were more common as compare to moderate & severe category in G.I & haematology related ADRs (p<0.05).
COVID-19 in India- Impact and Mitigation Strategies
Authors: Preysi Chauhan , K Saini Navreet , G Srinivasan , Heena Dabas
Published: July 2021

Background: The magnitude of the outbreak of corona virus disease (COVID-19) is exponentially increasing in world causing significant mortality and morbidity. Like other parts of the world, India is also struggling with COVID-19 crisis. As per data by the ministry of health and family welfare (MoHFW) till June 4, 2020, India had total 2,26,770 confirmed cases of COVID-19, out of which 1,10,960 were active cases, 1,09461 cured/discharged cases with 6348 deaths and one migration. Objective: This review deals with the impact of COVID-19 in India and the strategies adopted by theIndian government to mitigate the viral infection Data Sources: The studies published in the English language and indexed in PubMed were searched using MeSH terms COVID-19, impact, India, and health strategies. Data about strategies were acquired from the government of India official websites, government official news, and documents. Conclusion:Apart from the threat to lives, temporary unemployment, home-schooling of children, and lack of physical contact with family have highly impacted psychosocial health. To curtail the spread of COVID-19 India has implemented staged lockdown, social distancing norms, social media for public awareness, cluster containment, COVID-19 testing and treatment, vaccine trials and non- pharmacological interventions. India is advocating for the global collaboration to deal with relentless virus spread.
Effect of Physical Exercise in Remodeling Telomere Length and Cancer Prevention in an Epigenetic Prospect – A Systematic Review
Authors: Prathap Lavanya , Suganthirababu S Prathap , Kumar K Praveen , S Preetha
Published: July 2021

Background: Physical exercise has its impact at the molecular level and aids in healthy well-being of an individual. The current systematic review emphasis on the impact of physical exercise on the telomere length in cancer prevention through epigenetic mechanism. Evidences support the impact of physical exercise in alteration of telomere length through its influence in telomerase activity. The aim of the systematic review is to analyze the effect of physical exercise in remodeling the telomere length in cancer prevention in an epigenetic prospect. Material and Methods: We conducted a qualitative systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The systematic literature search covers articles ranging from the year 2010 to 2020. The Database used for literature searches are PubMed, Cochrane, Science Direct and Google scholar. The Medical Subject Headings (MeSH) used for search include ‘Cancer’ ‘exercise’ ‘Telomere length’ ‘telomerase expression’. The outcome variables include the telomere length, telomerase activity, telomere protein stabilizing gene expression status, Micro RNA expression status. Results: After exclusion of irrelevant articles 05 records are selected for final inclusion of the study and are analyzed using a Cochrane risk of bias assessment tool and SANRA tool found to be at low risk of bias and moderate quality respectively. The findings suggest chronic exercise is found to modulate the genetic and epigenetic equilibrium by either up regulation of p53 and p16 expression and stabilizing the telomerase activity within the limits or by increasing the telomerase activity and stabilizing the p53 and p16 expression within limits and impact telomere length, thus maintaining the genetic and epigenetic equilibrium. Conclusion: Based on the evidences collected it can be suggested that chronic moderate intensity aerobic exercise in a lifelong practice shows beneficial effects in a dose-response manner in cancer prevention in a novel way by modulating telomeres through epigenetic mechanism.
Evaluation of Adverse Drug Reactions caused by Topical Steroids in Patients Presenting in Dermatology Department of Teaching Institute of Tertiary Health Care Centre of Central India
Authors: Maheshwari Vatsala , Chaturvedi Richa , Meshram Sonali , Bhalsinge Rahul
Published: July 2021

Introduction : Topical steroids are most commonly being used today. Mostly these are being misused due to lack of awareness of their adverse effects. Malpractice and easy availability of these agents also responsible for their abuse. Aim : To Evaluate Topical Steroid abuse in various parameters according to CDSCO ADR forms. Objectives : This study was conducted to know the extent of abuse of topical steroid ,along with clinical profile and mode of accessibility in dermatology department of a teaching institute of tertiary health care centre of central India. Material and Method: First 200 patients of adverse drug reaction attending dermatology department were screened according to ICSR form of CDSCO in a period of December 2015 to November 2016 and 181 patients of them who gave history of topical steroid application were further analyzed. Result: Most commonly affected people belong to age of 21 to 30 years (41.98%),Tinea incognito (58%) was the commonest manifestation of steroid abuse, Tinea (58%)was the most common indication of steroid application, self medication (46.40%) was most common mode of steroid accessibility, betamethasone (61.87%) was most commonly applied topical steroid. Conclusion :Self medication and over the counter drug use were most common mode of steroid accessibility both can be controlled by making strict health regulatory policies . Simultaneously health education program must be targeted to young population who are more vulnerable to steroid abuse to make them aware regarding harmful effects of unguided or misguided use of topical steroid.
Influence of Lumbar Spinal Canal Dimensions on Neurological Claudication Symptomatology - A Case Control Study
Authors: Reddy Monika , Gangavelli Dr Ranganath , Priyanka Priyanka , Saikiran Dr P
Published: July 2021

Lumbar spinal stenosis (LSS) is abnormal narrowing of spinal canal of lumbar vertebrae causing compression of neural tissue which leads to a neurologic deficit. LSS is diagnosed based on clinical symptoms of patient and it is confirmed using MRI (Magnetic Resonance Imaging). The aim of the study is to determine the association between MRI lumbar spinal canal and foraminal dimensions in on neurological claudication symptomology. A total of 89 patients (45 males ,44 females, age range: 20-60 years) referred for MRI Lumbar spine were included in this prospective study. Patients were categorized into symptomatic (49 cases) and asymptomatic (40 controls) based on Edinburgh claudication questionnaire (ECQ). The Antero-posterior diameter of dural sac, Transverse diameter of dural sac, Cross sectional area of dural sac, Cross sectional area of lateral recess, Lateral recess depth, Angle of lateral recess, Ligamentous interfacet distance was measured from L3 to S1 on Axial T2 weighted MRI images. The strength of association between MRI measurements and clinical symptoms were assessed using logistic regression analysis and Cramer’s V test. The Phi coefficient value for the lumbar spinal canal, foraminal dimensions with neurogenic claudication symptomology based on ECQ was 0.108 & 0.207 respectively, which showed weak positive correlation. Our study concludes that MRI measurements of lumbar spinal canal and foraminal dimensions denoting LSS were found to show weak positive correlation with clinical symptoms assessed based on Edinburgh claudication questionnaire.
Effect of Methylcobalamin on Voltage-Gated Sodium Channels (Vgscs ) Expression in Neuropathic Painanimal Model
Authors: Mutiawati Endang , Lucas Meliala K.R.T. , Partadiredja Ginus , Adji Dhirgo , Wasito Raden
Published: July 2021

The objective of this study wasto assess the effect of methylcobalaminonmechanical allodynia and the voltage-gated sodium channels (VGSCs) expression of injured nerves in spinal nerve ligation-induced neuropathic pain model in animals.Three different doses of methylcobalamin were administrated intramuscularly into neuropathic pain rat model, twice a week for 14 weeks. The effect of methylcobalamin on neuropathic pain was assessed using mechanical allodynia (using the von Frey filaments) while its effect on VGSC expression was assessed using immunohistochemistry. ANOVA and independent t-test were employed to compared the effect of methylcobalamin on mechanical allodynia between groups.The size of von Frey filament that induced the first onset of mechanical allodynia was smaller in control group compared to 50µg methylcobalamin group (p=0.013) and methylcobalamin 100µg group (p=0.019). There is a dose–response relationship between methylcobalamin dose and the average duration of mechanical allodynia (43.8, 38.2, 30.6 and 29.6 days for control, 50µg, 100µg, and 150µg methylcobalamin group, respectively) with a significant different observed between control and 150µg methylcobalamin group only (p=0.027). Nerve tissues from all animals within control group expressed VGSC while all nerve tissues from both 100µg, and 150µg methylcobalamin, had no VGCS expression. In conclusion, methylcobalamin is potentially shorten the duration of mechanical allodynia and increase pain threshold in neuropathic pain animal model. These effects might associate with reduction of VGSC expression on the injured neurons.
Design of a Wireless Single Arm Electrocardiograph System
Authors: Raj. V Karthik , Sankaran J Tushar , Samantaray Soumya , Chakraborty Sayan , Saxena Srishti
Published: July 2021

Electrocardiograms (ECGs) are a method of assessment of cardiac electrical activity. It is the heart’s electrophysiological activity which occurs by the conduction of electrical impulses from the Sinoatrial (SA) node and the Atrioventricular (AV) node across the cardiac muscles and is displayed as a voltage-time graph. Conventionally, they have been acquired using a system of ten surface electrodes placed in different locations throughout the body in a 12-lead system. Single Arm ECG systems, where the ECG rhythm is obtained from only a single part of the body, replace the need for ten different electrodes to detect the heart's activity. Three pre-gelled electrodes are applied in different locations of the left arm to derive the sinus rhythm signal of a subject. An op-amp based hardware instrument has been developed for this purpose with active filters and amplifiers to perform signal conditioning. This paper demonstrates the implementation of a single arm hardware system of small size to improve portability, used as an ECG detection method and the results from various subjects taken at different gain values to improve the view of the signal, while also presenting a method to transmit the data of the signals wirelessly through an Internet-of-things (IoT) platform.
Maintenance of the Photovolatic Plants Using UAV Equipped with Low-cost GNSS RTK Receiver
Authors: Muhammad Bilal , Prasad Ramjee , Nisi2 Marco , Menichetti2 Fabio , Cianca Ernestina , Mennella Alberto , Gagliarde Graziano , Marenchino Davide
Published: July 2021

Global Navigation Satellite System (GNSS) Real Time Kinematic (RTK) employs high-end dual-frequency receivers and antennas to deliver precise positioning that, in some way, restricts the use of GNSSRTKto a subset of user market due to very high cost. The emerging mass-market user applications, however, require centimeter-positioning accuracy considering a cost-effective solution. This calls for low-cost GNSS RTK solutions to create new possibilities for mass-market user applications to make use of GNSS high accuracy positioning in a variety of ways. One of the applications, which makes use of low-cost GNSS RTK receiver, is the maintenance of photovoltaic (PV) plants using Unmanned Aerial Vehicle (UAV). This paper proposes a solution that aims at automating the maintenance of PV plant with enhanced reliability in a time and cost effective manner, which otherwise requires intermediate human intervention. The paper presents the architectural concept, system design, and end-to-end algorithm that plays a pivotal role in enabling the automatic report generation of PV plant status. Preliminary results of the proof-of-concept shows the feasibility of the proposed solution.
An Analysis of Global and Regional Mainstreaminess for Personalized Music Recommender Systems
Authors: Schedl Markus , Bauer Christine
Published: July 2021

The music mainstreaminess of a listener reflects how strong a person’s listening preferences correspond to those of the larger population. Considering that music mainstream may be defined from different perspectives, we show country-specific differences and study how taking into account music mainstreaminess influences the quality of music recommendations. In this paper, we first propose 11 novel mainstreaminess measures characterizing music listeners, considering both a global and a countryspecific basis for mainstreaminess. To this end, we model preference profiles (as a vector over artists) for users, countries, and globally, incorporating artist frequency, listener frequency, and a newly proposed TF-IDF-inspired weighting function, which we call artist frequency–inverse listener frequency (AF-ILF). The resulting preference profile for each user u is then related to the respective country-specific and global preference profile using fraction-based approaches, symmetrized Kullback-Leibler divergence, and Kendall’s τ rank correlation, in order to quantify u’s mainstreaminess. Second, we detail country-specific peculiarities concerning what defines the countries’ mainstream and discuss the proposed mainstreaminess definitions. Third, we show that incorporating the proposed global and country-specific mainstreaminess measures into the music recommendation process can notably improve accuracy of rating prediction.
Practical Attacks on Security and Privacy Through a Low-Cost Android Device
Authors: Paul Greig , Irvine James
Published: July 2021

As adoption of smartphones and tablets increases, and budget device offerings become increasingly affordable, the vision of bringing universal connectivity to the developing world is becoming more and more viable. Nonetheless, it is important to consider the diverse use-cases for smartphones and tablets today, particularly where a user may only have access to a single connected device. In many regions, banking and other important services can be accessed from mobile connected devices, expanding the reach of these services. This paper highlights the practical risks of one such low-cost computing device, highlighting the ease with which a very recent (manufactured September 2015) Android-based internet tablet, designed for the developing world, can be completely compromised by an attacker. The weaknesses identified allow an attacker to gain full root access and persistent malicious code execution capabilities. We consider the implications of these attacks, and the ease with which these attacks may be carried out, and highlight the difficulty in effectively mitigating these weaknesses as a user, even on a recently manufactured device.
Packet-Based Load Balancing in Data Center Networks
Authors: Kaymak Yagiz , Rojas-Cessa Roberto
Published: July 2021

In this paper, we evaluate the performance of packet-based load balancing in data center networks (DCNs). Throughput and flow completion time are some of the main the metrics considered to evaluate the performance of the transport of flows over the presence of long flows in a DCN. Load balancing in a DCN may improve those metrics but it may also generate out-of-order packet forwarding. Therefore, we investigate the impact of outof- order packet delivery on the throughput and flow completion time of long and short flows, respectively, in aDCN.We focus on per-packet load balancing. Our simulations show the presence of out-of-order packet delivery in a DCN using this load balancing approach. Simulation results also reveal that packetbased load balancing may yield smaller average flow completion time for short flows and larger average throughput for long flows than the single-path transport model used byTransmission Control Protocol (TCP), which prevents the presence of out-of-order packet delivery. Queueing diversity in the multipath structure of DCNs promotes susceptibility of out-of-order delivery. As the delay difference between alternative paths decreases, the occurrence of out-of-order packet delivery in packet-based load balancing also decreases. Therefore, under the studied scenarios, the benefits of the packet-based load balancing seem to outweigh the out-of-order problem.
Enhanced Ant Colony-Inspired Parallel Algorithm to Improve Cryptographic PRNGs
Authors: Keller Jorg , Spenger Gabriele , Wendzel Steffen
Published: July 2021

We present and motivate a parallel algorithm to compute promising candidate states for modifying the state space of a pseudo-random number generator in order to increase its cycle length. This is important for generators in low-power devices where increase of state space to achieve longer cycles is not an alternative. The runtime of the parallel algorithm is improved by an analogy to ant colony behavior: if two paths meet, the resulting path is followed at accelerated speed just as ants tend to reinforce paths that have been used by other ants. We evaluate our algorithm with simulations and demonstrate high parallel efficiency that makes the algorithm well-suited even for massively parallel systems like GPUs. Furthermore, the accelerated path variant of the algorithm achieves a runtime improvement of up to 4% over the straightforward implementation.1
Reconstruction automatique des entités d’un modèle BREP à partir d’un maillage déformé
Authors: Lohichi Borhen , BenAmara Abdelmajid , François Vincent
Published: July 2021

Nowadays, the integration of the different steps of mechanical design process (Design, analysis and manufacturing) is a necessity to reduce the time of design and optimization. This tendency of integrating CAD/CAM/Analysis and automation of the corresponding processes requires shared data between the various tasks using an integrated product model. Our research is oriented to CAD/CAM/Analysis integration by rebuilding the CAD model (BREP) starting from the FE results (deformed mesh). This paper presents techniques for rebuilding the geometrical and topological entities of the CAD model starting from a deformed mesh.
In vivo identification of soft biological tissues using MR imaging
Authors: Bouten Laura , Drapier Sylvain
Published: July 2021

Soft biological tissues constituting the human body are individually investigated regarding the identification of their mechanical properties. This study proposes an identification process of human legs tissues by coupling Magnetic Resonance Imaging (MRI) images with different levels of stocking used as mechanical loading. This loading may be compared with a compression around the whole leg section. The identification method relies on one hand on MRI image processing (digital image correlation, volume extraction, etc.) and on the other hand on a Finite Element Model combined with an optimization algorithm.
Exact and efficient interpolation using finite elements shape functions
Authors: Silva Gustavo H.C. , Riche Rodolphe Le , Molimard Jérôme , Vautrin Alain
Published: July 2021

The comparison of finite elements (FE) and experimental data fields have become ever more prevalent in numerical simulations. Since FE and experimental data fields rarely match, the interpolation of one field into the other is a fundamental step of the procedure. When one of the fields comes from FE, using the existing FE mesh and shape functions is a natural choice to determine mesh degrees of freedom at data point coordinates. This makes no assumptions beyond those already made in the FE model. In this sense, interpolation using element shape functions is exact. However, crude implementations of this technique generally display a quadratic computation complexity with respect to mesh size and number of data points, which is impractical when large data fields must be compared repeatedly. This document aims at assembling existing numerical procedures to improve the interpolation efficiency. With a combination of cross-products, bounding-boxes and indexing methods, the resulting algorithm shows linear computation cost, providing significant improvement in efficiency.
Influence of boundary conditions on strain field analysis for polycrystalline finite element simulations
Authors: Héripré Eva , Crépin Jérôme , Roos Arjen , Chaboche Jean-Louis
Published: July 2021

This paper presents a first validation of a novel methodology for identifying the parameters of a crystallographic elastoplastic constitutive law. This is accomplished by comparing simulation and experimental results at different length scales: the microstructure scale and the representative volume element scale. Experimentally, the microscopic strain fields and the microstrucural characteristics can be obtained only at the surface of the specimen. As a consequence, in finite element simulations only at the surface there is a oneto- one correspondence between the mesh and the experimental observed grain morphology. In this paper, the morphology of the subsurface grains is obtained by a simple extension in the thickness direction of the surface morphology. The aim of this study is then to verify whether the surface data contain sufficient information for the identification of the parameters of the constitutive law.
Application of a recycling Krylov subspace strategy for discrete element method applied to brittle crack problems
Authors: Gavoille Sylvain , Delaplace Arnaud , Rey Christian
Published: July 2021

This paper deals with a comparative study of two iterative Krylov solvers (GIRKS and SRKS) dedicated to the solution to a sequence of large linear problems. We apply these two algorithms to brittle crack problems modelized with a discrete element method. We show that these algorithms still reduce the total number of iterations but not the total CPU time. By considering the specific modification of the stiffness matrix for discrete modeling, we propose a simple evolution of the SRK algorithm leading to a reduction of the factor time (greater than 2). Efficiency of the algorithm is illustrated on 2D and 3D examples of crack propagation.
Effect of micro-defects on structure failure
Authors: Noël Virginie Bonnaillie- , Brancherie Delphine , Dambrine Marc , Tordeux Sébastien , Vial Grégory
Published: July 2021

This work aims at taking into account the influence of geometrical defects on the behavior till complete failure of structures. This is achieved without any fine description of the exact geometry of the perturbations. The proposed strategy is based on two approaches: asymptotic analysis of Navier equations and strong discontinuity approach.
On the use of proper generalized decompositions for solving the multidimensional chemical master equation
Authors: Chinesta Francisco , Ammar Amine , Cueto Elías
Published: July 2021

In this paper we review the possibilities associated with the use of Proper Generalized Decompositions for solving models established in highly multidimensional spaces. This technique has also been recently extended to problems that can be, under some circumstances, seen as multidimensional.
DDA in fluid-structure problems for the study of gravity dam failure
Authors: Kaidi Sami , Ouahsine Abdellatif , Rouainia Mohamed , Smaoui Hassan
Published: July 2021

In this paper, we present a 2D coupled fluid-structure interaction procedure to assess the stability of a cracked gravity dam against increasing water level. In this procedure the structure is assumed to be a discontinuous deformable solid containing pre-existing cracks. Thus, the Discontinuous Deformation Analysis DDA method is used to study the solid discontinuous medium, and the continuum finite element flow model to calculate the hydrostatic forces corresponding to the water level. The contact constraints between discrete blocks are imposed through an implicit augmented Lagrangian format. Numerical results show the potential of the proposed coupled model to quantify the direct influence of the nature and location of the internal cracks on the overall stability of common gravity dams.
A Review of Electro-Hydraulic Servovalve Research and Development
Authors: Tamburrano Paolo , Plummer Andrew R. , Distaso Elia , Amirante Riccardo
Published: July 2021

This paper provides a review of the state of the art of electro-hydraulic servovalves, which are widely used valves in industrial applications and aerospace, being key components for closed loop electrohydraulic motion control systems. The paper discusses their operating principles and the analytical models used to study these valves. Commercially available units are also analysed in detail, reporting the performance levels achieved by current servovalves in addition to discussing their advantages and drawbacks. Adetailed analysis of research that investigates these valves via computational fluid dynamic analysis is also provided. Research studies on novel control systems and novel configurations based on the use of smart materials, wh
Cyberbullying Detection in Social Networks: Artificial Intelligence Approach
Authors: Azeez Nureni Ayofe , Idiakose Sunday O. , Onyema Chinazo Juliet , Vyver Charles Van Der
Published: July 2021

Over the past decade, digital communication has reached a massive scale globally. Unfortunately, cyberbullying has become prevalent, with perpetrators hiding behind the mask of relative internet anonymity. In this work, efforts were made to review prominent classification algorithms and also to propose an ensemble model for identifying cases of cyberbullying, using Twitter datasets. The algorithms used for evaluation are Naive Bayes, K-Nearest Neighbors, Logistic Regression, Decision Tree, Random Forest, Linear Support Vector Classifier, Adaptive Boosting, Stochastic Gradient Descent and Bagging classifiers. Through experimentations, comparisons were made with the classifiers against four metrics: accuracy, precision, recall and F1 score. The results reveal the performances of all the algorithms used with their corresponding metrics. The ensemble model generated better results while Linear Support Vector Classifier (SVC) was the least effective of all. Random Forest classifier has shown to be the best performing classifier with medians of 0.77, 0.73 and 0.94 across the datasets. The ensemble model has shown to improve the results of its constituent classifiers with medians of 0.77, 0.66 and 0.94, as against the 0.59, 0.42 and 0.86 of Linear Support Vector Classifier.
SPDH - A Secure Plain Diffie-Hellman Algorithm
Authors: Tange Henrik , Andersen Birger
Published: July 2021

Secure communication in a wireless system or end-to-end communication requires setup of a shared secret. This shared secret can be obtained by the use of a public key cryptography system. The most widely used algorithm to obtain a shared secret is the Diffie–Hellman algorithm. However, this algorithm suffers from the Man-in-the-Middle problem; an attacker can perform an eavesdropping attack listen to the communication between participants A and B. Other algorithms as for instance ECMQV (Elliptic Curve Menezes Qo Vanstone) can handle this problem but is far more complex and slower because the algorithm is a three-pass algorithm whereas the Diffie–Hellman algorithm is a simple two-pass algorithm. Using standard cryptographic modules as AES and HMAC the purposed algorithm, Secure Plain Diffie–Hellman Algorithm, solves the Man-in-the-Middle problem and maintain its advantage from the plain Diffie–Hellman algorithm. Also the possibilities of replay attacks are solved by use of a timestamp.
A Model-Driven and Business Approach to Autonomic Network Management
Authors: Bezahaf Mehdi , Cassidy Stephen , Hutchison David , King Daniel , Race Nicholas , Rotsos Charalampos
Published: July 2021

As corporate networks continue to expand, the technologies that underpin these enterprises must be capable of meeting the operational goals of the operators that own and manage them. Automation has enabled the impressive scaling of networks from the days of Strowger. The challenge now is not only to keep pace with the continuing huge expansion of capacity but at the same time to manage a huge increase in complexity – driven by the range of customer solutions and technologies.

Recent advances in automation, programmable network interfaces, and model-driven networking will provide the possibility of closed-loop, self-optimizing, and self-healing networks. Collectively these support the goals of a truly automated network, commonly understood as “autonomic networking” even though this is a prospect yet to be achieved.

This paper outlines the progress made towards autonomic networking and the framework and procedures developed during the UK Next Generation Converged Digital Infrastructure (NG-CDI) project. It outlines the operator-driven requirements and capabilities that have been identified, and proposes an autonomic management framework, and summarizes current art and the challenges that remain.
Automatic Classification of Pararubber Trees in Thailand from LANDSAT-8 Images Using Neural Network Method
Authors: Supunyachotsakul C. , Suksangpanya N.
Published: July 2021

Classifying features from satellite images has been a time-consuming manual process which requires lots of manpower. This work exploits deep convolutional encoder-decoder neural network to develop an algorithm that can automatically classify the extents of the Pararubber tree-growing areas from the LANDSAT-8 images. The ground truth of the areas of the Pararubber tree was manually prepared and was separated into training datasets and the validation datasets. The classification model from this approach obtained using the training datasets was verified with the classification accuracy of70.90%, precision of 67.66%, recall of 80.80%, and F1 score of 73.59%.