bluuebunny/crossref_metadata_2025 huggingface dataset:
Hard X-Ray Emission Associated with White Dwarfs. IV. Signs of Accretion from Substellar Companions
Authors: Chu You-Hua , Toalá Jesús A. , Guerrero Martín A. , Bauer Florian F. , Bilikova Jana , Gruendl Robert A.
Published: April 2021

With an effective temperature of ≃200,000 K, KPD 0005+5106 is one of the hottest white dwarfs (WDs). ROSAT unexpectedly detected “hard” (∼1 keV) X-rays from this apparently single WD. We have obtained Chandra observations that confirm the spatial coincidence of this hard X-ray source with KPD 0005+5106. We have also obtained XMM-Newton observations of KPD 0005+5106, as well as PG 1159−035 and WD 0121−756, which are also apparently single and whose hard X-rays were detected by ROSAT at 3σ–4σ levels. The XMM-Newton spectra of the three WDs show remarkably similar shapes that can be fitted by models including a blackbody component for the stellar photospheric emission, a thermal plasma emission component, and a power-law component. Their X-ray luminosities in the 0.6–3.0 keV band range from 4 × 1029 to 4 × 1030 erg s−1. The XMM-Newton EPIC-pn soft-band (0.3–0.5 keV) light curve of KPD 0005+5106 is essentially constant, but the hard-band (0.6–3.0 keV) light curve shows periodic variations. An analysis of the generalized Lomb–Scargle periodograms for the XMM-Newton and Chandra hard-band light curves finds a convincing modulation (false-alarm probability of 0.41%) with a period of 4.7 ± 0.3 hr. Assuming that this period corresponds to a binary orbital period, the Roche radii of three viable types of companion have been calculated: M9V star, T brown dwarf, and Jupiter-like planet. Only the planet has a size larger than its Roche radius, although the M9V star and T brown dwarf may be heated by the WD and inflate past the Roche radius. Thus, all three types of companion may be donors to fuel accretion-powered hard X-ray emission.
Discovery and Characterization of a Rare Magnetic Hybrid β Cephei Slowly Pulsating B-type Star in an Eclipsing Binary in the Young Open Cluster NGC 6193
Authors: Stassun Keivan G. , Torres Guillermo , Johnston Cole , Stevens Daniel J. , Feliz Dax L. , Kounkel Marina , Bouma Luke G.
Published: April 2021

As many as 10% of OB-type stars have global magnetic fields, which is surprising given that their internal structure is radiative near the surface. A direct probe of internal structure is pulsations, and some OB-type stars exhibit pressure modes (β Cep pulsators) or gravity modes (slowly pulsating B-type stars; SPBs); a few rare cases of hybrid β Cep/SPBs occupy a narrow instability strip in the H-R diagram. The most precise fundamental properties of stars are obtained from eclipsing binaries (EBs), and those in clusters with known ages and metallicities provide the most stringent constraints on theory. Here we report the discovery that HD 149834 in the ∼5 Myr cluster NGC 6193 is an EB comprising a hybrid β Cep/SPB pulsator and a highly irradiated low-mass companion. We determine the masses, radii, and temperatures of both stars; the ∼9.7 M
⊙ primary resides in the instability strip where hybrid pulsations are theoretically predicted. The presence of both SPB and β Cep pulsations indicates that the system has a near-solar metallicity, and is in the second half of the main-sequence lifetime. The radius of the ∼1.2 M
⊙ companion is consistent with theoretical pre-main-sequence isochrones at 5 Myr, but its temperature is much higher than expected, perhaps due to irradiation by the primary. The radius of the primary is larger than expected, unless its metallicity is super-solar. Finally, the light curve shows residual modulation consistent with the rotation of the primary, and Chandra observations reveal a flare, both of which suggest the presence of starspots and thus magnetism on the primary.
Coupling effect in field Hall elements based on thin-film SOI MOS transistors
Authors: Leonov Aleksey V. , Murashev Victor N. , Ivanov Dmitry N. , Kirilov V.D.
Published: April 2021

The influence of the coupling effect on the parameters of field Hall elements based on thin-film MOS transistors has been studied. Analysis of the development of today’s microelectronics shows the necessity of developing the element base for high performance sensors based on silicon technologies. One way to significantly improve the performance of sensing elements including magnetic field sensors is the use of thin-film transistors on the basis of silicon on insulator (SOI) structures. It has been shown that field Hall sensors (FHS) may become the basis of high-performance magnetic field sensors employing the coupling effect occurring in the double gate vertical topology of these sensing elements. Electrophysical studies of FHS have been conducted for different gate bias and power supply modes. The results show that the coupling effect between the gates occurs in FHS if the thickness of the working layer between the gates is 200 nm. This effect leads to an increase in the effective carrier mobility and hence an increase in the magnetic sensitivity of the material. Thus field Hall elements based on thin-film transistors fabricated using silicon technologies provide for a substantial increase in the magnetic sensitivity of the elements and allow their application in highly reliable magnetic field sensors.
New Solutions and Methodologies for Data Acquisition and Management in Small Municipalities
Authors: Juliao Rui Pedro , Amorim Amilton , Hespanha João Paulo , Barros de Souza Guilherme Henrique , Messias Correia Ronaldo Celso , Destro Rafael Delli Colli
Published: April 2021

Promoting and managing sustainable territorial development require adequate tools that enable territorial managers to formulate appropriate choices. Technological solutions have emerged, and the paradigm has shifted from isolated GIS to a more collaborative production and dissemination of geographic data using spatial data infrastructures (SDI). A critical dataset for municipal land administration is cadastre. ISO 19152 standard of the Land Administration Domain Model (LADM) was published in 2012. Also, technology evolution, namely unmanned aerial vehicles (UAV), has changed data acquisition for cadastre. These are three pillars of modern territorial management: openness, co-production, and data sharing (SDI); models (LADM); affordable technology (UAV). This chapter presents how municipalities can develop an SDI project, incorporating LADM guidelines and UAV data acquisition. The case study is based on a group of 32 small municipalities from São Paulo state, in Brazil, known as UNIPONTAL.
From Macro to Micro
Authors: Tomás Lívia Rodrigues , Jurema Maria Carolina Barbosa , dos Santos Janaina Cassiano , Londe Luciana de Resende , Reani Regina Tortorella , Linhares Claudia de Albuquerque , Santos Leonardo B. L.
Published: April 2021

This chapter discusses urban mobility considering two main analyses approaches. Based on the relationship between mobility and vulnerability, the first approach analyzed commuter's vulnerability using basin as unit of analysis. The second one analyzes variables related to land use such as population density and its relation with job offer in the city and people's income using traffic zones as unit of analysis. The two scales dialogue and can be used concurrently. The municipality of São José dos Campos (Brazil) was used as a case study. Origin-destination research was the main database used in the analyses. Authors used geospatial tools, like spatial join operation and thematic maps, which enable the in-depth analysis of important data for urban studies or transport planning and can be replicated in any study area. The analysis of mobility data aggregated by basin contributed to an understanding of the implications of the urban configuration, with its displacement patterns related to water courses if any flooding or landslide occurs and interrupts people's flow.
Urban Transition and Its Impact on Mesoscale Weather
Authors: Rath Sudhansu S. , Panda Jagabandhu , Mohanty Srutisudha
Published: April 2021

Urban transition is an unstoppable process. Globally, several planning measures are taken by the city and country administration to control the sprawling process. Despite all the planning, most of the cities experience appreciable impact of urbanization on the localized weather parameters. This chapter summarizes the understanding relating to urban modification of localized weather, that is, changes in precipitation, temperature, and wind speed in the form of increase or decrease, their spatio-temportal distribution, urban heat island (UHI), and urban wind island (UWI). The impacts of the urbanization are primarily because of changes in land-surface characteristics due to the alteration of land use in a city. The urbanization effects on local or mesoscale weather could be studied both through observations and/or numerical modeling. The purpose of this chapter is to provide a review of most of the relevant studies carried out globally and with a special emphasis on India.
Green Walls as an Environmental Strategy
Authors: Sorte Pedro Dias Boa , Silva Caio , Calixter Abner L. , Romero Marta A. B.
Published: April 2021

Vegetation is an excellent strategy to tackle global warming and climate change. In this context, the green wall is a kind of green infrastructure that is used as a bioclimatic strategy. Also, it can be used as an approach to insert green areas in an urban context, contributing to urban areas to become more sustainable. This chapter aims to evaluate the thermal performance of green walls using three different native climbing vegetation from the Cerrado biome. Thus, the authors used a computational tool named ENVI-met (v.3) as a method to analyze and evaluate which plants would bring the best performance in terms of improving thermal comfort. The database the authors obtained from the simulations will serve as a comparison of the thermal performance between walls without vegetation cover, as well as clarify the morphological and physiological characteristics that influence its thermal performance. The results demonstrate that Arrabidaea pulchra species enabled green walls with lower temperatures and higher air humidity rate in most situations.
Counter-Mapping Practices in Land Regularization Through Geoinformation Technologies
Authors: Arruda Andrea Figueiredo , Henriques Cristina Delgado , Miranda Claudio Santos de
Published: April 2021

This chapter outlines the experience of the Épura Research and Extension Group of the Federal University of Mato Grosso for the identification, characterization, and demarcation of informal settlements in Cuiabá (Brazil). This involved cooperating with the local residents' associations and public authorities in recognizing local demands and the need to open up urban land regularization processes. The cartographic issue is central to the recognition and legitimization of these territories and the use of geoinformation technologies, namely geographic information systems and unmanned aerial vehicles, can increase the speed and accuracy of the mapping of the neighborhoods. Additionally, the demands for urban and housing improvements and provision of space for everyday activities can be highlighted through the visualization and measuring tools that are embodied in these technologies. Furthermore, the experience requires the university to play a role in seeking more participatory and proactive practices within urban planning processes.
Future 3D Urbanism
Authors: Estanqueiro Rossana , Tenedório José António , Rebelo Carla , Marques Joao Pedro
Published: April 2021

Urbanism has mainly used 2D data for both the urban analysis and diagnosis and the presentation of proposals for changes in the whole city or parts of the city. Even regarding the production of urban indicators, using, for example, the quantification of the existing green area in relation to the resident population, this practice is regularly based on the area and rarely on volume. This situation is mainly justified by the sluggishness and costs associated with obtaining 3D data. The recent development of data collection technology by unmanned aerial vehicles has triggered a change in this scenario. This chapter presents the UAV data acquisition and processing chain, analyses the positional accuracy of UAV data processing performed with GCP measurements obtained from GNSS, demonstrates how positional accuracy assessment and UAV workflow's quality control are relevant for ensuring the accuracy of derived UAV geospatial products, and demonstrates the usability of 3D models in a theoretical 3D urbanism context.
The K-12 Teacher's Perspective on Teaching and Learning During the COVID-19 Pandemic
Authors: Abernathy Dixie Friend , Thornburg Amy Wooten
Published: April 2021

In the spring of 2020, during the unprecedented COVID-19 pandemic, the nation's schools closed. Students were told to shelter in place at their homes and classroom teachers were charged with the challenge of educating over 50,000,000 K-12 students through online and virtual modalities. As this transition began in its early stages and then lingered for the remainder of the school year, attention and even scrutiny soon descended upon the actual preparation of teachers in executing such a transition, and the realistic success of doing so. Teachers began the new and unexpected process of teaching their students from home, and students, along with family support, began the practice of learning remotely. During this same time period, researchers were approved to conduct research focused exclusively on this educational phenomenon. One of the themes of this research was the K-12 teachers' perceptions on the teacher readiness and the overall effectiveness of this sudden switch to K-12 online teaching and learning.
Teacher Motivation During Emergency Distance Learning
Authors: Menglieva Elyanora Yusufovna , Manzoor Fareeha
Published: April 2021

The rapid shift to virtual teaching in response to the COVID-19 pandemic has resulted in emergency remote teaching (ERT) and has highlighted the numerous multilevel challenges associated with it in the countries from the Global South. This chapter aims to explore how this shift to remote teaching has affected English language teachers' level of motivation and how they have adapted to it. In addition, this study offers quantitative and qualitative insights into the effectiveness of the resources employed by EFL/ESL teachers. This is done by analyzing the surveys of 34 teachers and interviews of four teachers from Uzbekistan and Pakistan. Through thematic analysis of the interviews, a detailed account of the challenging factors and their coping strategies were found. This chapter concludes with a discussion on the lessons learned and recommendations on how to make a relatively smoother transition to remote teaching.
Perceptions of Online Learning
Authors: Ceglie Robert John , Black Ginger C.
Published: April 2021

This chapter examines the parent/guardian perceptions of the rollout and implementation of online instruction during the move to online instruction during the COVID-19 pandemic. The authors begin this chapter with an examination of how the transition to online learning occurred for K-12 public schools in North Carolina starting in March 2020. They explore the current landscape and environment for this type of learning within this state and describe what supports and tools were in place prior to the move to remote learning. They discuss the best practices for online learning in K-12 schools and explore the research that exists on parental opinions and beliefs of education and online instruction. While this literature is not particularly robust, it provides a foundation for the work of which they engaged. Next, they discuss the findings from a survey that was sent to parents in North Carolina and describe the implications for this information. Finally, they offer suggestions for future considerations of ways to act on the parental perspectives.
Using Online Learning Environments With Kindergarten Children During the COVID-19 Emergency
Authors: Benvenuti Martina , Chioccariello Augusto , Panesi Sabrina
Published: April 2021

This chapter explores kindergarten children's use of specific online applications such as WhatsApp and YouTube to maintain social relationships between each other and with their classroom teachers during the COVID-19 pandemic lockdown. Using Vygotskian theorisation of learning through interaction with more expert people (teachers and parents) and Leontev's theory of functional organ, this study verifies that children often learned without an expert's presence, using strategies such as trial and error and discussion, and through maintaining social relationships among themselves and with their teachers. Specifically, the study involved two Italian kindergartens (42 children) and six teachers. Analysis of the children's work and of teacher interviews shows that, during the Italian lockdown, the pre-school children used applications as learning environments in the form of functional organs, and this proved useful for carrying on kindergarten activities and for maintaining social relationships.
Online Scratch Programming With Compulsory School Children During COVID-19 Lockdown
Authors: Benvenuti Martina , Freina Laura , Chioccariello Augusto , Panesi Sabrina
Published: April 2021

In Spring 2020, the COVID-19 health emergency caused all Italian schools to close from March to the end of the school year. An intervention was organized with the aim of offering primary and lower secondary teachers the possibility to organize remote coding activities with their students. Nine workshops were held to introduce teachers to the Scratch online programming environment, and then a coding day was organized involving students from the last year of primary and lower secondary schools. The chosen activities proved to be motivating to the students, favoring social interactions and participation, and increasing their interest in coding. Teachers were positively impressed by the ease with which their students managed programming in Scratch, but some of them felt that they did not master programming well enough to autonomously support class activities. A longer teacher training period is needed.
Pandemic Pages
Authors: Zimmer Wendi K. , Hodges Tracey S.
Published: April 2021

While transforming instruction to online delivery methods, educators cannot ignore the importance of teaching writers and writing skills for student success. In this chapter, two higher education writing instructors use their unique experiences and the challenges they faced during the COVID-19 shift in Spring 2020 to discuss strategies for teaching during a pandemic. The instructors discuss the challenges, opportunities, and creativity they utilized to ensure their students received high-quality, engaging writing instruction during unprecedented times. Specifically, they explore four themes and provide resources that encompass the experiences shifting their courses from face-to-face or hybrid to fully online: (1) re-envisioning courses for the virtual setting, (2) making teaching shifts, (3) assessing how the virtual setting helped or hindered teaching, and (4) reflecting on practices learned from the shift to plan future semesters. These themes and resources may inform higher education's virtual writing instructional practices.
Emergent Instructional Strategies for a Performance-Based Course That Is Taught Virtually
Authors: Cornelius Joe D.
Published: April 2021

This chapter will focus on strategies for educators teaching courses relying on a performance-based set of practices but are forced to teach virtually. By reflecting on the author's personal experience of teaching a hybrid module course in Spring 2019 and teaching completely online towards the end of the semester of Fall 2020, Cornelius will touch on several observations from recent times to propel proposed solutions, tips, and advice. Highlighting lessons learned during the transition and useful resources, this chapter will focus on strategies to lessen the blow of teaching a course rooted in practice during a pandemic and how to dial it back towards a theory-based course while maintaining most or all intended learning outcomes. In light of the pandemic, there will be a large amount of weight on the theory side; how does one find the counterweight? While lending towards an innovative side while thinking of solutions, the chapter will describe ideas that educators may want to attempt to facilitate hands-on learning at home.
Pivoting to Deeper Experiences in Education
Authors: Eadens Danielle M. , Eadens Daniel W.
Published: April 2021

The COVID-19 pandemic led educators to quickly pivot to continue teaching. Negative effects include exacerbated academic achievement gaps between SES groups, less access to health services, aggravated digital divides, widened academic achievement gaps, and enormously interrupted the education processes. Positive changes include educator optimism for digital portfolios, simulated lesson planning, and delivery; supports for social-emotional engagement; seamless transitions to remote learning; and seeing recalcitrant individuals revise and adapt teaching formats, relationship-building, increased quality online education, and motivation to try innovations. Relational humanity is an integral part of the faculty-student relationship; showing students they matter as humans and deepening relationships with them is a humanitarian act. The pivot forced variations, created disequilibrium, celebrated innovations, and yielded creative delivery models. Faculty are now re-examining their content and delivery in the spirit of creating an improved student experience for all modalities of instruction.
It's Just a Jump to the Left
Authors: Hersey Leigh Nanney
Published: April 2021

In Spring 2020, many U.S. universities abruptly shifted to online course delivery in response to the quickly rising coronavirus cases. While these shifts impacted all students and faculty, they were particularly difficult for courses that had included community-based projects as assignments. This chapter examines the adjustments made for two courses with community-based projects. It explores how learning objectives were still met through virtual opportunities. The chapter also identifies challenges during the process. Faculty can use this knowledge to design community-based projects that include virtual options from the beginning.
Technology and Gross World Product
Authors: Hooke Angus , Alati Lauren
Published: April 2021

This chapter divides the economic history of humans into technological eras and uses a population multiplied by per capita income approach to estimate gross world product in each era and, therefore, for the history of humankind. It also provides an overview of the major technologies that introduced each era and supported growth during the era. The chapter uses a model developed by the authors to predict gross world product during the remainder of the 21st century (2021-2100). It also considers which economies might have been the largest in the world since the dawn of civilisation about 6,000 years ago. The chapter concludes with the prediction that China, India, and the United States will remain the dominant economic powers during the remainder of the 21st century, that the gross domestic product (GDP) of India will pass that of the United States in the late 2030s and the GDP of China in the late 2040s, and will be more than 50% larger than that of second-placed China by 2100.
Technology Convergences to Enhance Education, Health, and Community Self-Sufficiency and Resilience
Authors: MacRae Don
Published: April 2021

This chapter considers existing and emerging technology convergences leading to advances in education and health as well as in other areas such as plant-based food production. Some advances will be enhanced by scientific research and technology directed to supporting life in outer space. A proposed revival of crofting and crofting communities throughout the highlands and islands of Scotland serves to illustrate how technological convergences and related growth of business could contribute to improved performance in the target areas as well as achieve high levels of self-sufficiency and post-COVID resilience of communities worldwide.
Biotechnology
Authors: Ma Qing-Ping
Published: April 2021

Biotechnology utilizes biological systems or living organisms to create, develop, or make products. This chapter reviews the current state of biotechnology and examines its future trends. Currently, biotechnology plays key roles in medicine, agriculture, and industry. In medicine, vaccines which still rely on biological systems for their production, are the best tools to prevent infectious diseases; antibodies and RNA/DNA probes have been crucial in detecting and treating diseases; and genetic editing and gene therapy is making it possible to treat hereditary diseases. In agriculture, biotechnology is generating crops that produce high yields and need fewer inputs, crops that need fewer applications of pesticides, and crops with enhanced nutrition profiles. In industry, biotechnology is being utilized in food processing, metal ore processing, the production of chemicals, and reducing energy consumption and pollution.
The Transition to Online Teaching and Learning
Authors: Whateley Greg , Manly Alan
Published: April 2021

The onset of the COVID-19 pandemic in early 2020 provided both a need and an opportunity for educational institutions in Sydney to explore new ways of providing teaching and learning for their students. UBSS was able to respond quickly because it had already prepared to introduce online learning. In mid-2019, the institution had decided to offer an online option and a senior staff member and support staff had been working since then to convert existing product into suitable online format. By the time the demand for online teaching and learning arrived, the institution was already well placed for the conversion.
Security and Privacy in FinTech
Authors: Hussain Muzammil , Nadeem Muhammad Waqas , Iqbal S. , Mehrban Sobia , Fatima Syeda Nisar , Hakeem Owais , Mustafa Ghulam
Published: April 2021

Financial technology (FinTech) has dramatically changed the way of banking and financial services. Computer programs and other technology which used to provide and enable financial services is named as FinTech. However, these services face several security and privacy issues while providing financial services to the users. These services and applications must be secured to enhance the acceptance and usability of these services among the users. The main aim of this research is to provide a policy framework to ensure the security and privacy of user information in financial technology, since FinTech applications and services carry quite sensitive data of its users. This policy framework provides a comprehensive set of policies to secure FinTech services. These policies must be implemented in each organization providing FinTech services.
E-Banking Security
Authors: Rossi Fabio Diniz , Hohemberger Rumenigue , Konzen Marcos Paulo , Temp Daniel Chaves
Published: April 2021

The online banking industry has overgrown in recent years and will continue to grow as economic organizations remain to encourage customers to handle online banking transactions such as money transfers, access to account information, or payment of monthly bills. During this period, internet criminals and fraudsters attempting to steal personal customer information hijacked online banking. This article proposes reviewing the ways by which fraudulent activities are performed and what banks are doing to prevent such activities, as well as the new security measures that banks are using to increase customer confidence. Therefore, the authors present the threats, challenges to address such threats, some trends, and future landscapes regarding online banking security.
Impact of Mobile Money on Financial Crime, Money Laundering, and Terrorism Financing
Authors: Oyoo Gilbert Ouko
Published: April 2021

Financial crime, money laundering, and terror financing have been perennial menaces that downplay the major headway made in the financial transaction space. Businesses and individuals have found it prudent to always try remaining ahead of the perpetrators behind the vices. The springing into life of the mobile money in the second half of the first decade of this century has revolutionized the manner with which risk management in this respect is handled. In this chapter, the author posits that although mobile money has led to greater financial inclusion, the rate with which the myriad financial crimes have been reported over the past decade in the face of this phenomenon raises the need to stay abreast of developments in this space.
The Use of Technology Acceptance Model in Mobile Banking
Authors: Bilir Kadriye Burcu Öngen
Published: April 2021

This chapter aims to determine the variables that explain using mobile banking. This study identifies and investigates the factors that influence the adoption of mobile banking, and specifically focuses on the evaluation of mobile banking application with users or non-users. The research model includes the basic concepts of the technology acceptance model. The technology acceptance model (TAM) tries to explain the adoption process and underlying influencing factors in technology acceptance. The survey was conducted to gather data which was coded in SPSS 17. Confirmatory factor analysis was used to analyze data, and structural equation modeling using Amos 17 software was used to validate the research model. The result shows that perceived ease of use, perceived usefulness, and perceived normative pressure significantly influences customer attitude, which affects the adoption of mobile banking.
Continuance Usage of Mobile Banking Services Among Small and Medium Enterprises (SMEs) in Tanzania
Authors: Mandari Herman E. , Koloseni Daniel Ntabagi , Macha Julius
Published: April 2021

The study examines the intention to continue using mobile banking services among SMEs in Tanzania. The study extended the ECS-IS model by adding three variables: ease-of-use, perceived trust, and attitude to address the existing challenges in continuance usage of mobile banking services. Data was collected using a self-administered questionnaire from company's owners and managers. A total of 287 responses were used in data analysis. SEM technique was employed to evaluate the measurement and structural models. The study found that satisfaction and attitude have a direct influence on continuance usage of mobile banking among SMEs in Tanzania. Furthermore, confirmation, perceived trust, and perceived usefulness have an indirect effect on continuance usage of mobile banking services among SMEs. The study provides useful insights which could be used by mobile banking service providers to improve banking services delivered through mobile technology. Furthermore, the findings will assist scholars in understanding the antecedents which affect continuance usage of mobile banking services among SMEs.
An Efficient Algorithm to Produce Sponge Packing Particles
Authors: Barkai Ofer , Vitner Gadi
Published: April 2021

The primary research goal was to develop an algorithm for efficiently cutting quadrangular-shaped raw material into smaller quadrangular pieces; one that would reduce to a minimum the percentage of actual waste during the cutting process. The raw material that is the subject of this article is sponge, a material used widely in the furniture industry. Each raw material piece was sliced into smaller pieces for use in a specific product. The algorithm enables product manufacturing with minimal waste by defining a changeable length and a permanent width of the slice, along with the width and length of the product itself. The study suggests that the length of the raw material piece affects the percentage of the reduction. The manufacturer could control waste by pre-planning the length of the piece of spongy raw material. The reduction by waste of usable material before the study was 15%. After the conducted simulation, which tested the effectiveness of the algorithm, the percentage of unusable material decreased to 4% or less a year.
A Humanitarian Green Supply Chain Management Considering Minimum Cost and Time
Authors: Sengupta Dipanjana , Das Amrit , Bera Uttam Kumar , Dutta Anirban
Published: April 2021

Disaster is the sudden problem of the world. There is no time bound. By disaster, all the creatures of the earth are affected. Here, the authors have tried to show some issues which are related to the natural calamities and green transportation. The main investigation of the paper is to describe about humanitarian supply chain management with optimized transportation cost, time, and carbon emission. Here a real-life problem of flood affected area has been chosen. When such disasters happen, quick response can reduce the devastation and save lives, and thus, it requires fulfilling the basic humanitarian needs of the affected population. In such case, organizations should also maintain the emission of the vehicles in safe range to mitigate the further disaster by pollution. A multi-objective solid transportation problem considering cost, time, and emission has been presented here. To solve the problem, this paper has used goal programming method and pareto optimal solution method. A comparison of results is also shown later. Some managerial insights are drawn to describe the situation.
Pricing and Ethical Issues for Global Markets
Authors: Mandal Pratap Chandra
Published: April 2021

Multinationals operating in global markets require analyzing several pricing considerations. They require setting appropriate prices of their products for each of the markets they operate in. Price of a product is an important criterion which decides whether a product will get sold or not. Companies contend with a number of issues in pricing like geographical pricing, price escalation, transfer prices, dumping charges, pricing for emerging markets, and pricing for individuals at the bottom of the pyramid. There are several legal and ethical aspects in pricing. These include deceptive or illegal prices – deceptive reference pricing, loss leader pricing, and bait and switch approach towards pricing; predatory pricing; price discrimination; and price fixing. The contribution of the study is that it conducts a conceptual analysis of the literature on pricing strategies and ethical issues. The analysis is validated by collecting and analyzing information from literature. It discusses how multinationals facing such situations should handle them, establish their businesses in global markets, and generate substantial revenues and profits.
Assessing the Impact of the COVID-19 Crisis on the Socio-Economic Situation in Africa
Authors: Ceesay Ebrima K.
Published: April 2021

This article assesses the impact of the COVID-19 pandemic on the social and economic situation in Africa. The data used in this paper was generated from online survey questionnaire, in which the participants were asked questions about how COVID-19 has affected their socio-economic lives. The questionnaire was designed to help Africa to understand COVID-19 impacts. The results reveal that COVID-19 affected Africa in the following ways: 1) 51.6% responded that coronavirus affected their job search; 2) over the past three months, 47.1% of the respondents said their private financial situation remained unchanged; 3) 61% did not trust the existence of COVID-19; 5) according to this online survey administered using Google form, 51.8% of the respondents said the services sectors are the most impacted sectors, followed by industrial sector, 31.3%, and agriculture is least affected sector at 8.4%. Policy implication is that it has serious impacts on socio-economics interactions.
A Correlation-Based Feature Selection and Classification Approach for Autism Spectrum Disorder
Authors: Verma Manvi , Kumar Dinesh
Published: April 2021

Autism spectrum disorder (ASD) is a medical condition in which an individual has certain behavior abnormalities, language impairment, and communication problems in the social world. It is a kind of a neurological setback that hinders the ability of an individual. In this work, an effort is made to propose an efficient machine learning-based classifier to assess the individuals on the parameters laid down for ASD based upon the traits captured from the ASD-affected individuals. The standard dataset of 1,054 toddlers is taken, which consists of two categories of toddlers, namely affected by ASD and not affected. The dataset contains 17 features, amongst which 12 features have been selected using correlation-based feature selection, and the random tree classifier gave the best overall performance with an accuracy of 98.9% with 17 features and 99.7% with the selected feature set. The results thus obtained have been compared with other state-of-the-art methods, and the proposed approach outperforms most of them.
Deep Learning-Based Knowledge Extraction From Diseased and Healthy Edible Plant Leaves
Authors: Jindal Udit , Gupta Sheifali
Published: April 2021

Agriculture contributes majorly to all nations' economies, but crop diseases are now becoming a very big issue that has to be resolving immediately. Because of this, crop/plant disease detection becomes a very significant area to work. However, a huge number of studies have been done for automatic disease detection using machine learning, but less work has been done using deep learning with efficient results. The research article presents a convolution neural network for plant disease detection by using open access ‘PlantVillage' dataset for three versions that are colored, grayscale, and segmented images. The dataset consists of 54,305 images and is being used to train a model that will be able to detect disease present in edible plants. The proposed neural network achieved the testing accuracy of 99.27%, 98.04%, and 99.14% for colored, grayscale, and segmented images, respectively. The work also presents better precision and recall rates on colored image datasets.
An Improved Separable and Reversible Steganography in Encrypted Grayscale Images
Authors: Duevedi Manisha , Muttoo Sunil Kumar
Published: April 2021

Reversible data hiding in encrypted images (RDH-EI) has attracted various communities that deal with security. Xiao et al. presented RDH-EI that uses pixel value ordering (PVO) and additive homomorphism for encryption ensuring that the embedding capacity of plain and encrypted image remains relatively same. However, the size of location map required to manage over/under flow blocks increased drastically reducing the overall embedding capacity. In the paper, a new PVO-based separable RDH scheme is proposed using double encryption. The original image is encrypted using chaotic mapping in Phase 1, ensuring that the performance of PVO algorithm in an encrypted domain is similar to that in plain domain. Secret data is embedded in this encrypted image. The embedded image is re-encrypted using additive homomorphism to enhance security. The proposed scheme is more efficient as it improves the pure embedding rate and total embedding capacity of the image by reducing location map size, overcoming the drawback of Xiao et al.
(p+, α, t)-Anonymity Technique Against Privacy Attacks
Authors: Sowmyarani C. N.  , Gadad Veena , Dayananda P.
Published: April 2021

Privacy preservation is a major concern in current technology where enormous amounts of data are being collected and published for carrying out analysis. These data may contain sensitive information related to individual who owns them. If the data is published in their original form, they may lead to privacy disclosure which threats privacy requirements. Hence, the data should be anonymized before publishing so that it becomes challenging for intruders to obtain sensitive information by means of any privacy attack model. There are popular data anonymization techniques such as k-anonymity, l-diversity, p-sensitive k-anonymity, (l, m, d) anonymity, and t-closeness, which are vulnerable to different privacy attacks discussed in this paper. The proposed technique called (p+, α, t)-anonymity aims to anonymize the data in such a way that even though intruder has sufficient background knowledge on the target individual he will not be able to infer anything and breach private information. The anonymized data also provide sufficient data utility by allowing various data analytics to be performed.
Data Provenance and Access Control Rules for Ownership Transfer Using Blockchain
Authors: Kumar Randhir , Tripathi Rakesh
Published: April 2021

Provenance provides information about how data came to be in its present state. Recently, many critical applications are working with data provenance and provenance security. However, the main challenges in provenance-based applications are storage representation, provenance security, and centralized approach. In this paper, the authors propose a secure trading framework which is based on the techniques of blockchain that includes various features like decentralization, immutability, and integrity in order to solve the trust crisis in centralized provenance-based system. To overcome the storage representation of data provenance, they propose JavaScript object notation (JSON) structure. To improve the provenance security, they propose the access control language (ACL) rule. To implement the JSON structure and ACL rules, permissioned blockchain based tool “Hyperledger Composer” has been used. They demonstrate that their framework minimizes the execution time when the number of transaction increases in terms of storage representation of data provenance and security.
Improved Extended Progressive Visual Cryptography Scheme Using Pixel Harmonization
Authors: Bhagate Suhas , Kulkarni Prakash J.
Published: April 2021

Security of information is of much concern in the modern internet era. Secret sharing schemes provide mechanism of encrypting secret information to prevent illicit usage. Visual cryptography is a secret sharing technique that facilitates encryption of a secret image. Visual cryptography allows us to effectively and efficiently share secrets among a number of trusted parties by hiding secrets within images. These images are encoded into multiple shares as per the rules indicated in basis matrices and later decoded by stacking required number of shares. Progressive visual cryptography has a specialty of recovering secret image as soon as more than one shares received gradually. Existing progressive visual cryptography schemes have severe limitations like data disclose on shares and higher pixel expansion. Improved progressive visual cryptography scheme deals with these limitations. Improved extended progressive visual cryptography scheme solves the issue of management of noise like meaningless shares by creating meaningful shares without any pixel expansion efficiently.
A Novel Research in Low Altitude Acoustic Target Recognition Based on HMM
Authors: Liu Hui , Wang Wei , Wang Chuang Wen
Published: April 2021

This paper introduces an improved HMM (hidden Markov model) for low altitude acoustic target recognition. To overcome the limitation of the classical CDHMM (continuous density hidden Markov model) training algorithm and the generalization ability deficiency of existing discriminative learning methods, a new discriminative training method for estimating the CDHMM in acoustic target recognition is proposed based on the principle of maximizing the minimum relative separation margin. According to the definition of the relative margin, the new training criterion can be equation as a standard constrained minimax optimization problem. Then, the optimization problem can be solved by a GPD (generalized probabilistic descent) algorithm. The experimental results show that the performance of the algorithm is significantly improved compared with the former training method, which can effectively improve the recognition ability of the acoustic target recognition system.
Intellectual Properties Integration
Authors: Boumaza Rima , Boutekkouk Fateh
Published: April 2021

Intellectual properties (IPs) integration is becoming more challenging due to the increasing complexity of systems on chip as well as their components. Since no survey is available about this topic, this paper is written to help recently interested researchers in the field to have an idea about IP integration. This paper tries to put the light on IP integration challenges over time and how researchers and industrials have dealt with every challenge. On the other hand, the emergence of the standard IP-XACT for packaging, integrating, and reusing intellectual properties has enabled the development of many integration tools and the enhancement of the already existing ones. In this regard, different solutions are presented in this paper before and after the emergence of the standard enriched with a discussion of different proposed solutions including an attempt to define what is needed to be done else. At the end, the paper concludes by considering a promising tendency that hopefully will mitigate some of IP integration gaps.
A Lightweight Three-Factor Anonymous Authentication Scheme With Privacy Protection for Personalized Healthcare Applications
Authors: Shuai Mengxia , Yu Nenghai , Wang Hongxia , Xiong Ling , Li Yue
Published: April 2021

Security and privacy issues in wireless medical sensor networks (WMSNs) have attracted lots of attention in both academia and industry due to the sensitiveness of medical system. In the past decade, extensive research has been carried out on these security issues, but no single study exists that addresses them adequately, especially for some important security properties, such as user anonymity and forward secrecy. As a step towards this direction, in this paper, the authors propose a lightweight three-factor anonymous authentication scheme with forward secrecy for personalized healthcare applications using only the lightweight cryptographic primitives. The proposed scheme adopts pseudonym identity technique to protect users' real identities and employs one-way hash chain technique to ensure forward secrecy. Analysis and comparison results demonstrate that the proposed scheme can not only reduce execution time by 34% as compared with the most effective related schemes, but also achieve more security and functional features.
Microstructural Investigation of Fluoroapatite Hydrothermally Converted from Hydroxyapatite Synthesized from Crocodile Eggshell
Authors: Auniq Reedwan Bin Zafar , Lerdrattranataywee Weerapong , Boonyang Upsorn
Published: April 2021

Fluoro/hydroxyapatite (FHAp) were prepared by hydrothermal at 150 °C for 24 hours with different of starting materials. The conversion of hydroxyapatite (HAp) and tricalcium phosphate to FHAp showed the rod-like shape with 200 nm. While, the morphology of FHAp from crocodile eggshell as CaCO3 form with different in phosphorus and fluoride source showed the unique structure evolution from rod-like hexagonal crystals, dumbbell to ball shape. Two distinctive morphology, first when using NaF as fluoride source with (NH4)2HPO4 precursor show the large cubic structure in high magnification it is tufted hexagonal crystal and it bundle like structure. As the pH value decreases in NH4F, it increases crystal size. For H3PO4 as phosphate precursor found that unique structure evolution from rod-like hexagonal crystals to dumbbell structure and then form the sphere assembly with a size of several micrometers.
Revisiting Current Concepts on the Tolerogenicity of Steady-State Dendritic Cell Subsets and Their Maturation Stages
Authors: Lutz Manfred B. , Backer Ronald A. , Clausen Björn E.
Published: April 2021

The original concept stated that immature dendritic cells (DC) act tolerogenically whereas mature DC behave strictly immunogenically. Meanwhile, it is also accepted that phenotypically mature stages of all conventional DC subsets can promote tolerance as steady-state migratory DC by transporting self-antigens to lymph nodes to exert unique functions on regulatory T cells. We propose that in vivo 1) there is little evidence for a tolerogenic function of immature DC during steady state such as CD4 T cell anergy induction, 2) all tolerance as steady-state migratory DC undergo common as well as subset-specific molecular changes, and 3) these changes differ by quantitative and qualitative markers from immunogenic DC, which allows one to clearly distinguish tolerogenic from immunogenic migratory DC.