bluuebunny/crossref_metadata_2025 huggingface dataset:
A safe semi-supervised graph convolution network
Authors: Yang Zhi , Yan Yadong , Gan Haitao , Zhao Jing , Ye Zhiwei
Published: August 2022

In the semi-supervised learning field, Graph Convolution Network (GCN), as a variant model of GNN, has achieved promising results for non-Euclidean data by introducing convolution into GNN. However, GCN and its variant models fail to safely use the information of risk unlabeled data, which will degrade the performance of semi-supervised learning. Therefore, we propose a Safe GCN framework (Safe-GCN) to improve the learning performance. In the Safe-GCN, we design an iterative process to label the unlabeled data. In each iteration, a GCN and its supervised version (S-GCN) are learned to find the unlabeled data with high confidence. The high-confidence unlabeled data and their pseudo labels are then added to the label set. Finally, both added unlabeled data and labeled ones are used to train a S-GCN which can achieve the safe exploration of the risk unlabeled data and enable safe use of large numbers of unlabeled data. The performance of Safe-GCN is evaluated on three well-known citation network datasets and the obtained results demonstrate the effectiveness of the proposed framework over several graph-based semi-supervised learning methods.
Digital Competence of Digital Native Students as Prerequisite for Digital Transformation of Education
Authors: Tóth Tomáš , Virágh Roderik , Hallová Marcela , Stuchlý Peter , Hennyeyová Klára
Published: August 2022

Current students of higher education institutions are referred to as digital natives and so they are expected to have a good level of digital competence. The aim of the paper is to examine whether digital native students of non-technical study programs consider themselves ready for the digital transformation of education and whether, from their point of view, they meet the preconditions for such digital education. A survey (questionnaire) was conducted for this purpose. The results showed that most students have appropriate technical support for online education (technical equipment, internet connection and access to the necessary software). Most students have a positive attitude towards the use of digital technologies in general and specifically in education too. This result is consistent with the characteristics of digital natives. Consistency was also found in their self-assessment of their own level of technical skill (77.4% of students do not need help working with digital technologies or only to a small extent and 84.4% of students can actively participate in online education). The results also indicate students’ propensity for multitasking as a feature of digital natives (during online education, 77% of students use multiple devices at once and a total of 85.2% of students also engage in other activities during online learning). Most students are also satisfied with the support of the subjects they study in the form of e-courses. However, the preference for a particular form of study materials (printed or digital) is not such ambiguous.
The Effectiveness of Knowledge Combination in e-Learning Management System (eLMS)
Authors: Muhisn Zahraa Abed Aljasim , Almansouri Saif , Muhisn Sinan , Ahmad Mazida , Omar Mazni
Published: August 2022

Information and Communication Technology (ICT) play an important role in maintaining Knowledge Management (KM) processes, because of the potential significance of knowledge management in improving the performance of higher educational institutes in particular. KM is acquiring increased relevance as a topic worth exploring. e-Learning Management System (eLMS) has been recognized and known as effective and powerful in supporting teaching and learning opportunities around the world as well as being a method of delivering education, knowledge and flexibility to higher education institutions, eLMS has been a significant step forward in the evolution of knowledge management systems.Thus, the purpose of this empirical study was to see how effective knowledge combination in eLMS is among Iraqi students. A survey research approach was adopted to achieve these goals, with a sample of 109 undergraduate students from Iraq's College of Information Technology, all of whom were actively participating in eLMS activities. The initial result showed that the knowledge can be productively transferred from teachers and lecturers to students via eLMS. Furthermore, eLMS enable students to increase their knowledge through the combination process, also students are able to integrate and use multiple knowledge sources to enhance their learning process.
Online Education During the Pandemic: A Systematic Literature Review
Authors: Ozdamli Fezile , Karagozlu Damla
Published: August 2022

With the pandemic, there was an urgent transition to online education. In this process, challenges were experienced while benefiting from the opportunities of online education. This research aims to identify the existing literature on online education in higher education institutions during the pandemic and to highlight the opportunities and challenges reported in research in this process. The study was carried out as a systematic literature review. The results show that maintaining social distance and increased confidence in the effectiveness of e-learning are the main opportunities. The lack of practice, especially in medical applications, limited ICT resources, and pedagogical deficiencies in online environments are shown as challenges of online education during the pandemic. It is thought that this study will make significant contributions to the online education process post-pandemic. The results from this study reinforce previous study findings and identify research that will make the online learning process more effective. Based on the results obtained, suggestions are given for future online learning studies.
A Survey Investigating the Key Factors and Theoretical E-Learning Frameworks During Crisis Periods
Authors: Mahmood Yaser Sh. , Dbouk Mohamed , Sbeity Ihab , Ibrahim Zein
Published: August 2022

In the previous ten years, there has been an astounding expansion in the study and application of e-learning frameworks. The recent literature and e-learning ideas were investigated in this study, with e-learning research’s different parameters being précised. E-learning processes’ associated services, technology, as well as stakeholders, are the three principal aspects of e-learning systems. A typology of services comprising e-learning models is presented in a framework, with stakeholders, technology, and learning approaches being included. Accordingly, the aforementioned aspects are considered through a detailed literature review, with e-learning frameworks’ relationship with the different classified stakeholder groups also clarified. Finally, ways to resolve the foremost challenges identified through the literature review are posed, with our e-learning system also presented. Furthermore, the proposed answer may direct and facilitate the appropriate appraisal of learners, educators, and educational facilities by decision-makers, drawing on data provided through live interaction.
The Spatial Spillover Effect of College Students’ Entrepreneurial Activeness Degree
Authors: Chen Huanhuan , Wang Chunbao , Pang Jin
Published: August 2022

Analyzing the influence of the spatial spillover effect of college students’ Entrepreneurial Activeness Degree (EAD) in each region on the cultivation intensity of their Innovation and Entrepreneurial Ability (IEA) is of certain theoretical and practical significance. However, in the research of domestic scholars, when studying the relationship between the EAD of college students and the cultivation intensity of their IEA, they generally give comprehensive evaluations based on the Evaluation Index Systems (EISs) they built, few of them have concerned about the spatial spillover effect of the EAD of college students, and relevant analysis based on spatial measurement method is rarely seen. To fill in this research blank, this paper aims to study the spatial spillover effect of the EAD of college students based on the improvement of IEA. At first, the paper gave the analysis framework of EAD, and adopted a layer-by-layer vertical and horizontal scatter degree method to perform dynamic measurement on the EAD of college students based on evaluation data collected from different regions. Then, this paper built a college student innovation and entrepreneurial Knowledge Production Function (KPF) model and used it to analyze the relationship between IEA cultivation intensity and the EAD of college students, thereby attaining the development status and spatial spillovers of the entrepreneurial activities of college students. At last, experimental results proved the effectiveness of the measurement method and the constructed model, and the analysis results of the spatial spillover effect in the study regions were given.
A Novel Approach for Product Recommendation Using Smartphone Sensor Data
Authors: Moontaha Nishat Chowdhury  , H M Zabir Haque  , Kazi Taqi Tahmid  , Fatema-Tuz-Zohora Salma  , Nafisa Ahmed
Published: August 2022

Human Activity-based studies have become an omnipresent research topic in Machine Learning. Considering the countless impacts of human activity on persons' everyday life, we have analyzed the correlation between human activity and their product preferences in our study and proposed that daily human activity could be a metric for product recommendation models. To address this previously unaccounted phenomenon, a new approach is presented in our study that gives real-time recommendations to users by observing their activeness in daily life. However, product recommendation systems mostly believe in ratings, and the purchase behavior of users instead of investigating the precious insights of users' daily activities. But we examined smartphones' GPS sensor data using machine learning algorithms to urge insights from users' daily activeness and proposed a model for predicting the product of interest of the purchasers, based on the activeness of their daily life. Moreover, based on our model, we have introduced a prototype of a real-time recommendation system, especially for the retail shops that rely on users' implicit data from smartphone sensors to form product recommendations. For conducting our study, we developed an android application that—collects embedded smartphone sensor data and can detect objects to provide product recommendations and product details. Experiment shows, that our proffered daily activeness-based recommendation system using smartphone sensor data, performs with a precision of 66%, but it is also a promising performance because it does not use customers' explicit feedback.
Android and Web-Based Learning Research During the Last 10 Years: How Does It Impact Physics Learning?
Authors: Prahani Binar Kurnia , Jatmiko Budi , Saphira Hanandita Veda , Amelia Tan
Published: August 2022

There are many benefits from using AbL and WbL, especially in the learning process through all subjects. Also, it is necessary always to discover novelty, innovation, improvement, and development of AbL or WbL to increase the quality of the study environment. This research analyzes bibliometrics on ‘AbL’ and 'WbL' keywords and compares them. Scopus is used to collect the metadata, and the VOSViewer application will be an assist tool. This research is expected to reach trends, patterns, novelty, and future research in the AbL and WbL through broad fields of Education during the past ten years (2012-2021). The research results show that trends of AbL and WbL research tend to increase each year. Finally, based on the analysis of the selected papers, the use of AbL, should be more boarder and widely in the classroom. Furthermore, the use of WbL also tends to be effective and efficient. Using WbL in classrooms is believed can improve several skills of students. But, it is necessary to find a better design to improve the learning concepts in integrating WbL. These findings also can be a recommendation for future research that optimizes AbL for the teaching and learning process in schools or universities/institutions. However, the use of appropriate learning media can improve and provide a positive response from many aspects of education in the classroom, especially in generating knowledge in abstract material like a physics subject.
A Systematic Literature Review of Keyphrases Extraction Approaches
Authors: Ajallouda Lahbib , Fagroud Fatima Zahra , Zellou Ahmed , Benlahmar El habib
Published: August 2022

The keyphrases of a document are the textual units that characterize its content such as the topics it addresses, its ideas, their field, etc. Thousands of books, articles and web pages are published every day. Manually extracting keyphrases is a tedious task and takes a lot of time. Automatic keyphrases extraction is an area of text mining that aims to identify the most useful and important phrases that give meaning to the content of a document. Keyphrases can be used in many Natural Language Processing (NLP) applications, such as text summarization, text clustering and text classification. This article provides a Systematic Literature Review (SLR) to investigate, analyze, and discuss existing relevant contributions and efforts that use new concepts and tools to improve keyphrase extraction. We have studied the supervised and unsupervised approaches to extracting keyphrases published in the period 2015-2022. We have also identified the steps most commonly used by the different approaches. Additionally, we looked at the criteria that should be evaluated to improve the accuracy of keyphrases extraction. Each selected approach was evaluated for its ability to extract keyphrases. Our findings highlight the importance of keyphrase extraction, and provide researchers and practitioners with information about proposed solutions and their limitations, which contributes to extract keyphrases in a powerful and meaningful way effective.
Development of a New Chaotic Maps Cryptosystem with Quadratic Residue Problem
Authors: Tahat Nedal Mohammad , Shaqbou'a Rania , Abu-Dalu Maysam , Qadomi Alaa
Published: August 2022

A new fast public key cryptosystem is proposed, which is based on two dissimilar number-theoretic hard problems, namely the simultaneous chaotic maps (CM) problem and quadratic residue (QR) problem. The adversary has to solve the two hard problems simultaneously to recover the plaintext according to their knowledge about the public keys and the cipher-text. Cryptographic quadratic residue and chaotic system are employed to enhance the security of our cryptosystem scheme. The encryption, and decryption are discussed in details. Several security attacks are proposed to illustrate the system shield through chaotic maps and quadratic residue problems. The performance analysis of the proposed scheme show a much improved performance over existing techniques.
An Efficient Tasks Scheduling Algorithm for Drone Operations in the Indoor Environment
Authors: Hulaj Astrit , Bytyci Eliot , Kadriu Veronë
Published: August 2022

This research proposes an efficient algorithm that can be applied to drones to transport materials in indoor environment. This algorithm optimizes the time and reduces energy consumption during sharing and completing tasks between different drones. In this research, the results will be achieved based on the "Earliest Time Algorithm". We have modified this algorithm, where we have reached to get much better results in terms of saving time while performing various tasks from the drone. The performance of the algorithm is tested and analyzed for three different types of tasks and depending on the weight the drone carries.
Simulation Optimization for Location and Allocation of Emergency Medical Service
Authors: Umam Muhammad Isnaini Hadiyul , Santosa Budi , Siswanto Nurhadi
Published: August 2022

Emergency medical services are an essential element in the modern healthcare system. Health care services are the most important because they play an important role in saving people's lives and reducing rates of mortality and morbidity. Especially during the covid-19 pandemic and the new normal era makes this problem very interesting to discuss. For this reason, this study tries to overcome the problem location and allocation of MES by using a combination of metaheuristics and simulation. The approach taken to overcome these challenges is developing Symbiotic Organisms Search algorithm and then use the simulation method to validation the result. The transition of the ambulance system from a centralized to decentralized system by using the M-SOS algorithm, found that to shorten the response time to 9 minutes, need to combine the 5 core bases with about 12 potential bases. From the simulation scenarios tested, the total number of ambulances involved in the proposed system is 16 units. So it can be concluded that involving several potential bases can produce a short response time.
Hybrid Cyber-Security Model for Attacks Detection Based on Deep and Machine Learning
Authors: Mahmood Naser Shaymaa , Hussain Ali Yossra , Al-Jumeily OBE Dhiya
Published: August 2022

Nowadays, numerous attacks can be considered high risks in terms of the security of Wireless Sensor Networks (WSN). As a result, different applications are introduced to manage the data and information exchange and related security sides to be save in transmission of data. Recently, most of the security attacks are classified as cyber ones. These attacks interest in the system halting and destroying the data rather than stealing the data. In this paper, a cyber-attacks detection system is proposed based on an intelligent hybrid model that uses deep and machine learning technologies. The proposed model improves the cyber-attack detection speed. In addition, a feature reduction model is proposed using machine learning methods (PCA and SVD) to select the most related features to the adopted classes of attacks. This can positively affect the deep-learning model complexity. The obtained results demonstrate the superiority of the proposed hybrid model-based cyber detection system in comparison to the traditional ones in reaching an accuracy of 99.98%, 100%, 100%, 100% for precision, recall, and F1-measure respectively, and reducing the time to 23s for the datasets of Message Queuing Telemetry Transport-Dataset (MQTT-DS) and Wireless Sensor Networks Dataset (WSN-DS).
André Gide & la Seconde Guerre mondiale
Authors: Van Tuyl Jocelyn
Published: August 2022

Homme de lettres au rayonnement sans égal en France pendant les premières décennies du xxe siècle, André Gide devient une figure contestée mais emblématique pendant la Seconde Guerre mondiale. Ses écrits de guerre proposent une image exemplaire des défis auxquels fait face un écrivain majeur en période d’effondrement national. Retraçant le tortueux « itinéraire intellectuel » de Gide à partir de la débâcle jusqu’à l’épuration, cet ouvrage examine le rôle ambigu du doyen des lettres françaises, dont les manœuvres complexes permettent d’aborder de façon privilégiée trois questions de grande importance : la relation entre littérature et politique pendant la Seconde Guerre mondiale, les refoulements et les repositionnements qui continuent à alimenter la controverse à propos de cette période, enfin le rôle des intellectuels reconnus en temps de crise nationale.

À l’exception du Journal datant du début de la guerre, la critique s’est peu intéressée aux publications de Gide pendant les années sombres. Jocelyn Van Tuyl scrute tous ces textes en détail, retrace l’évolution des opinions politiques de Gide et, surtout, lit ces écrits de guerre les uns à la lumière des autres. Car c’est l’interaction entre ces textes qui révèle toute la complexité des positions politiques de Gide et la virtuosité rhétorique que l’auteur déploie pour redresser son image ternie.
André Gide & Jean Amrouche
Authors: Gide André , Amrouche Jean
Published: August 2022

Composée de près de 150 lettres échangées entre 1928 et 1950, cette correspondance s’est développée principalement à partir de 1943, date à laquelle Jean Amrouche ayant conquis à Tunis l’amitié de Gide devient l’un de ses interlocuteurs privilégiés.

Une première période permet surtout de faire connaissance avec Amrouche, ce Kabyle qui vient à Gide sans rien renier de sa culture, et qui espère même la développer au contact de l’influence française.

La seconde période (120 lettres entre 1943 et 1950) constitue un document d’histoire littéraire, dans la mesure où la fondation de l’Arche en 1943 va d’abord unir les efforts des deux hommes à Alger, puis entraîner Amrouche dans le maquis éditorial parisien. L’autre grande affaire de ces relations est la préparation, puis la réalisation des entretiens radiophoniques, Amrouche inventant un genre qui allait être sa plus belle réussite. De façon plus discrète se révèle une dimension historique : après les démêlés de Gide avec les communistes, c’est Amrouche qui se trouve de plus en plus écartelé entre son amour de la culture française et sa fidélité à ses origines.

Au total, c’est un dialogue complet qui s’établit, donnant à la figure du dernier Gide un éclairage nouveau en la replaçant dans l’atmosphère de l’après-guerre.
André Gide & Paul-Albert Laurens
Authors: Gide André , Laurens Paul-Albert
Published: August 2022

Composée de 130 lettres échangées entre 1891 et 1934, cette correspondance retrace l’histoire d’une amitié de jeunesse prolongée dans l’âge mûr : celle de l’écrivain André Gide et du peintre Paul-Albert Laurens (1870-1934), fils du célèbre peintre d’histoire Jean-Paul Laurens.

Au cours de leur voyage en Afrique du Nord en 1893-1894, épisode décisif longuement évoqué dans Si le grain ne meurt, et auquel les lettres ici rassemblées apportent quantité d’éclairages inédits, Laurens et Gide partagent leurs découvertes touristiques et sexuelles et nouent une relation fraternelle, au point d’en faire une des plus durables et profondes que Gide ait connues.

Cette amitié est aussi un réseau : fils unique et bientôt orphelin, Gide a trouvé, avec Paul-Albert Laurens, son frère Pierre et leurs parents, une seconde famille ; il a rencontré enfin, avec eux, un milieu d’artistes et d’écrivains qu’il n’a plus quitté.
André Gide & Robert Levesque
Authors: Gide André , Levesque Robert
Published: August 2022

Quand Robert Levesque fait, en 1926, la connaissance d’André Gide, il n’a que 17 ans, mais est déjà le protégé de Marcel Jouhandeau et l’ami de Max Jacob, que sa sensibilité et ses dons poétiques ont conquis. Gide représente un modèle de vie pour l’adolescent, qui le fait profiter en retour de sa faculté d’enthousiasme. Un équilibre s’établit vite, qui permet à cette amitié, d’abord littéraire, de s’approfondir. Amoureux de l’aventure, Robert a souvent l’occasion d’approuver la générosité de Gide, avant de partir avec lui et de devenir, en Italie, en Grèce, en Egypte, son compagnon de voyage idéal. Devenu un familier du « clan Gide » et de la NRF, Robert Levesque est un témoin et un confident privilégié. Les 250 lettres de cette correspondance, complétées par des extraits du Journal de R. Levesque, nous font découvrir un Gide inhabituel, « contemporain capital » rajeunissant auprès d’un nouveau Nathanaël.
André Gide & André Ruyters 2
Authors: Gide André , Ruyters André
Published: August 2022

Voici, jusqu’ici entièrement inédite, une des correspondances les plus importantes d’André Gide, tant par le nombre des lettres échangées (près de 600, sur plus d’un demi-siècle) que par la diversité des intérêts qui lièrent l’auteur des Nourritures terrestres, dès 1895, avec André Ruyters, écrivain belge précoce (il a alors dix-neuf ans) et original, qui sera avec lui l’un des six “pères fondateurs” de La Nouvelle Revue Française (dont il fut le gérant jusqu’à la guerre de 1914).Cette correspondance fera sortir de l’ombre où elle était restée la figure, singulière et attachante, d’un des plus proches amis de Gide, dont tous les lecteurs de celui-ci connaissaient le nom, mais en ignorant tout (il est à peine mentionné dans les biographies de l’écrivain) de celui qui fut le dédicataire d’Isabelle. On verra vivre ici une amitié, d’abord tendre et passionnée, puis orageuse et subissant de violentes ruptures, mais perdurant jusqu’à la mort de Gide. Outre son intérêt documentaire et biographique, cet ensemble de lettres, où chacun lit, explique et commente les œuvres de l’autre, est surtout précieux d’un point de vue purement littéraire : sur les Nourritures de Gide, sur Le Mauvais-Riche de Ruyters, sur l’art de la traduction (à propos du Typhon de Conrad traduit par Gide), sur de multiples questions de grammaire et de morale..., on découvrira ici nombre de lettres passionnantes, dont la lecture est indispensable pour la connaissance de Gide et de l’histoire littéraire de son temps.L’édition de cette correspondance est due à la collaboration de Claude Martin, auteur de nombreux ouvrages sur Gide (en particulier sur sa correspondance), et d’un des meilleurs connaisseurs de la littérature belge de l’époque, Victor Martin-Schmets, éditeur des Oeuvres complètes d’André Ruyters ; Pierre Masson, auteur d’une étude publiée naguère aux PUL (André Gide, voyage et écriture, 1983) s’est joint à eux pour la présentation de ce monument épistolaire.
Spatialisation des établissements cisterciens dans les anciens diocèses de Clermont et du Puy au Moyen Âge
Authors: Bouvard-Mor Emma , Tronchère-Cottet Hervé
Published: August 2022

Résumé : Le maillage territorial généré par les dix abbayes et domaines cisterciens dans les anciens diocèses de Clermont et du Puy avait jusque-là très peu intéressé la recherche, tant le corpus est maigre et l’ordre peu représentatif du monachisme auvergnat et vellave. Nos recherches ont pourtant mis en évidence que ces monastères ont participé de façon significative au paysage religieux et économique microrégional entre le premier tiers du xiie siècle et l’aube du xiiie siècle. Nous avons eu recours à des méthodes d’analyses spatiales, notamment les calculs d’accessibilité (« distance-coût »/« distance-temps ») qui permettent une approche du territoire vécu à deux échelles : les relations entre chacune des abbayes et leur temporel, puis les éventuelles relations entre chacun des domaines abbatiaux. Les documents d’archives convoqués (série H du clergé régulier), complétés par des sources secondes, sont relativement indigents. Par conséquent, l’incomplétude et l’hétérogénéité des matériaux d’étude sous-tendent des biais que nous aborderons pour chacun des points développés.
Innovative Knowledge Automation Framework in DM and Collaborative Edge Computing Social IoT Systems
Authors: Zhang Qiansha , Li Gang
Published: August 2022

Digital marketing-based innovative knowledge management helps people inspire creativity and cultural changes required to advance the organization and satisfy changing business requirements. Knowledge workers can respond more rapidly when they have quicker access to resources and information across the company. A knowledge-based approach views innovation as a process characterized by the knowledge needed to understand how the innovation was created. The term “digital marketing automation” (DMA) refers to software platforms and technologies built for marketing departments and enterprises to sell online and automate tedious tasks more effectively. Digital marketing encompasses all forms of advertising that take place online, including but not limited to websites, search engines, social media, email, and mobile apps. An entirely new approach to big data processing has emerged because of the rise of edge computing in the internet of things environment. As a result of these findings, a distributed neural network cloud-edge computing paradigm is presented.
Application of Microbial Degradation Technology in Oil Pollution Control
Authors: Bi Mingjuan , Zheng Fushan , Wang Fengxiang , Chen Tiantian , Cui Yingying
Published: August 2022

Oil pollution is still a problem that is very difficult to control. To this end, this study investigates the application effect of microbial degradation technology in oil pollution control. First, the degradation microbial strains and substrates were determined according to the type of microorganisms. Then, ultraviolet spectrophotometry was used to determine the concentration of crude oil in the culture medium. After that, the authors designed the flow chart of crude oil standard curve, extracted organic phase, determined the residual oil composition in the culture medium, and calculated the degradation rate of mixed bacteria to crude oil. By studying the degradation mechanism of aerobic bacteria, anaerobic bacteria, and fungi, the degradation products were confirmed and the treatment of oil pollution on the water surface was carried out. It can be seen from the experimental results that the microbial degradation technology is effective in solving the problem of oil pollution.
Integrating Mobile Mixed Reality to Enhance Learning Before, During, and After Physical Field Trips
Authors: MacCallum Kathryn , Parsons David
Published: August 2022

Physical field trips have long been used in education, but virtual field trips are increasingly being used to enhance them. This article focuses on the use of mixed reality to enhance a physical field trip before, during, and after the field experience as part of a project in teacher professional development. The context is a field trip to a landfill site, where students learn about waste management, recycling, and sustainability. Building on several different themes from the literature to create a single model of pre-, intra-, and post-field trip digital learning activities, three scenarios are outlined: One where a virtual field trip is used prior to a physical field trip to prepare students for their visit, a second where an augmented reality experience is used during the physical field trip, and a third where students build on their experience of virtual reality to create their own virtual tours. The article highlights how mobile mixed reality offers new ways to deepen the field trip learning experience through student- and teacher-created digital artifacts.
A Co-Word and Co-Citation Analysis of Digital Marketing Research
Authors: Pham Xuan Lan , Nguyen Phuong Minh Binh , Truong Giang Nu To
Published: August 2022

As one of the most recent forms of marketing, digital marketing has emerged as the fastest-growing sector of the industry. A large number of academic studies have been published on different aspects of this field. The main objectives of this paper are to illustrate the evolution of the marketing field, examine the research focuses, and identify the future trends of digital marketing research using a combined bibliometric approach of co-word and co-citation analysis. Using the Web of Science (WoS) database, a representative set of 254 academic publications was selected and analyzed by VOSviewer software. The co-citation results represent four main research clusters, including digital marketing and business performance, opportunities and challenges, digital marketing development and research methodology, and digital marketing and customer behaviour. Similarly, the results of the co-keyword analysis reveal six themes, including foundation, digital marketing implications, digital marketing channels, content marketing, business sectors, and emerging trends.
Zooming Through a Crisis
Authors: Gertz Nolen
Published: August 2022

The coronavirus pandemic has led the world not to shut down but to move from the physical to the virtual. Various technologies have been used to maintain a sense of normalcy during the pandemic, as we can now work online, shop online, and socialize online. The perceived success of this technological resiliency in the face of a global health crisis has given rise to questions about whether the move from the physical to the virtual should be maintained even after the pandemic. Given the possibility that this “new normal” could soon become simply what is considered as “normal,” this paper will investigate what it means that we have indeed been able to use technologies to maintain order in a time of global disorder. To answer this question, this paper will focus on the technology that has become most synonymous with the pandemic—Zoom—and use postphenomenology, critical theory of technology, and Arendt's political philosophy in order to investigate its use during the pandemic.
Tensile Strength Enhancement of the Bamboo Fiber Hand Sheet by Fiber Arrangement
Authors: Kaima Jerachard , Preechawuttipong Itthichai , Peyroux Robert , Jongchansitto Pawarut , Sillard Cecile , Viguie Jeremie , Mauret Evelyne
Published: August 2022

In order to improve the tensile strength of bamboo hand sheets used as reinforcement in bio composite materials, bamboo fibers have to be arranged roughly in the same direction. However, the classical method for forming the bamboo hand sheet (using L’HOMARGY machine) is not efficient to align the fibers. The objective of this work is to improve the method for forming the suitable arranged direction of the bamboo hand sheets. The bamboo strips were treated with a 6% NaOH solution at 120oc for 2 hours before extracting as individual bamboo fibers. These bamboo fibers were then formed as bamboo hand sheet by a dynamic laboratory sheet former (Mecaform, EP MECA, France). The given hand sheets were then cut along different angles (0, 45, and 90 degrees), and ten samples of each unidirectional and classical bamboo hand sheet were tested for the tensile strength according to ISO 1924-1. It was found that the tensile strength and the tensile modulus of bamboo hand sheets are correlated. The tensile strength and the tensile modulus of the 0-degree arranged bamboo hand sheets are double improved compare with the classical bamboo hand sheets.
Effect of Different Supported Heteropoly Acid on the Catalytic Hydrothermal Conversion of Cellulose into Formic Acid
Authors: @ Zaibidai Adil Nor Liyana Zakira binti Zabidi Adi , binti Azhari Azzusyaza , binti Harun Farah Wahida , Saharuddin Tengku Shafazila binti Tengku
Published: August 2022

Cellulose, an abundant biomass, has received considerable attention as a renewable precursor to the formation of valuable chemicals. The overall strategy in this research is to produce formic acid from cellulose by using direct catalytic hydrothermal method. In this study, a heterogeneous catalyst system was developed by preparing different types of HPA on hydrotalcite. The three types of HPA- HT are phosphotungstic acid-hydrotalcite (PTA-HT), phosphomolybdic acid-hydrotalcite (PMA-HT) and silicotungstic acid-hydrotalcite (STA-HT); were prepared by the impregnation method. These prepared catalysts were characterized using FTIR, XRD and FESEM-EDX. The catalytic reaction was carried out in a hydrothermal reactor and the FA production was determined using HPLC-DAD. Comparison was made during the investigation where calcined HT was used for cellulose conversion and compared with each HPA-HT. All three catalysts were successfully impregnated on the calcined HT, as proven by XRD, FTIR, and EDX. According to the finding, PMA-HT give the highest cellulose conversion (48%) and FA yield (9.61%) followed by PTA-HT (32% converted cellulose with 7.35% FA yield) and STA-HT (17% cellulose converted and 2.87%). This phenomena occur due to the acidity and moderate redox properties of molybdenum in PMA. Herein, we reported effects of different HPAs on HT towards FA yield.
Impact of Different PAA Solid Content Applied to Polyimide-Based Resistive Random Access Memory
Authors: Huang Jia Sih , Liu Tang Yi , Chen Hsing Jui , Tseng Tze Ruei , Yang Wen Luh
Published: August 2022

This study investigated the impact of different Polyamic Acid (PAA) solid content on Polyimide (PI) film precursors, adjusting the molecular chain density after dehydration and cyclization to improve the operating voltage and leakage current of resistive random access memory (RRAM). This work modulated 1.5%, 5%, and 15% PAA solutions to form PI film as a resistance switching layer. After modulating the molecular chain density in the PI film, the goal is to improve the device’s operating characteristics. According to the result, the PI film with a higher concentration can achieve a lower operating electric field and reduce the leakage current, improving operational stability and reliability.
Influence of Seawater Treatment Duration on Physico-Mechanical Properties of Banana Trunk Lignocellulosic Fibers
Authors: Akatwijuka Osbert , Abdel-Mawgood Ahmed , Gepreel Mohamed Abdel Hady , Yamamoto Mitsuo , Hassanin Ahmed H.
Published: August 2022

The revolution towards using lignocellulosic agro-residues as polymer composite reinforcements compels a fresh look at the entire operations from inception to final composite products. Chemical treatment is a frequently reported method that enhances interfacial and fiber-matrix adhesion properties. However, our study utilised seawater treatment for fiber surface modification as an eco-friendly and cost-effective approach compared to the toxic chemical reagents. Banana trunk layers were immersed in seawater for 7, 14, 21, and 28 days at ambient conditions before fiber extraction. Our results revealed that the treatment duration affected the extracted fibers’ physico-mechanical properties compared to untreated fibers. Scanning electron microscopy showed significant alterations in fiber surfaces. At optimum treatment duration, we found that treated fiber density increased to 1.31 g/cm3, cross-sectional area decreased by 45.6 % and tensile strength increased to 389 Mpa. This research was undertaken to demonstrate the potential of utilizing the abundant non-potable seawater for banana fiber extraction process as a way of lessening use of toxic chemicals and freshwater scarcity in the desert and arid regions.
Mechanical Properties and Morphological Analysis of High-Density Polyethylene/Poly(Ethylene Glycol) Methacrylate/Rice Husk Composite
Authors: Arenas Alyssa Sarah E. , Escutin Chelsea Mae L. , de Yro Persia Ada N.
Published: August 2022

Polymers that are low-cost, lightweight, durable, and eco-friendly can be considered as one of the aims of recent research studies to solve environmental problems, especially those caused by the abundance of plastic wastes. The notable mechanical properties of such polymers could be achieved with reinforcements such as using natural fibers like hemp, sisal, wood-fiber, jute, and the focus of the study, rice husk. Using high-density polyethylene (HDPE) as the matrix, the addition of rice husk fillers was able to improve the mechanical properties of the polymer composites. However, the microstructure of the composite seems to be uneven, and voids could be observed. This must be due to disturbances or inhomogeneity in the interfacial dispersion of the filler (rice husk) and the matrix (polyethylene). This paper aims to introduce a poly (ethylene glycol) methacrylate (PEGMA) compatibilizer that can help provide stronger interfacial dispersion between the filler and matrix to improve the mechanical properties and morphology of the composite. It also offers a broader perspective regarding the possible component combinations and ratios in fabricating polyethylene which may, later on, lead to the manufacture of more efficient polyethylene-based products.
Property-Structure Relationship on the Mechanics of Carbon Nanotube Yarns
Authors: Pérez-Aranda César , Pech-Pisté Raúl , Carrillo-Escalante Hugo , Vargas-Coronado Rossana , Hernández-Sánchez Fernando , Ríos-Soberanis Carlos Rolando , Cauich-Rodríguez Juan , Avilés Francis
Published: August 2022

Carbon nanotube yarns (CNTYs) are twisted hierarchical fibers which exhibit a strong property-structure relationship. Understanding of the property-structure relationship of CNTYs will allow their use in structural and energy dissipation (damping) applications. For this reason, the morphology and structure of dry-spun CNTYs are characterized by means of Raman spectroscopy mapping, atomic force microscopy, and scanning electron microscopy and correlated to their quasi-static and dynamic mechanical properties. The continuous CNTYs present some degree of structural variability, which explains the variability measured in their dynamic mechanical response. Under tension, 42.3 μm diameter (0.71 porosity) CNTYs reach specific strengths of ~0.8 N/tex and ultimate strains ranging from 4% to 7%. Mechanical hysteresis tests under incremental cyclic strain show that the CNTYs exhibits high energy dissipation, which concur with dynamic mechanical analysis (DMA). DMA shows that CNTYs are unconventional materials with high specific stiffness (per unit weight) as well as a very high damping ratio. The damping ratio increases with temperature and reach ~0.6 at 60 °C. The mechanical response of the CNTYs under tension can be explained mainly from changes in the hierarchical structural conformation of the yarn, rather than from changes in the carbon nanotube bond distance or inherent material properties.
Effect of the Addition of Aggregates Derived from Used Tires on the Mechanical Behavior of Clay
Authors: Meziani Faroudia , Amar Kahil , Mourad YAMOUN
Published: August 2022

The study of the shear strength parameters of mixtures comprising tire-derived aggregates (TDA) and clay was the main objective of this experimental work. The tests were performed using the direct shear box. First, the test was performed on specimens comprising only clay in its natural state and then on mixtures consisting of clay and TDA in increasing contents. A total of four samples (natural clay and natural clay with 2, 4, and 6% tire-derived aggregates)) were made and tested at three normal stress levels (100, 200, and 300 kPa). Then, Mohr-Coulomb failure envelopes were drawn to determine the internal friction angle and cohesion for all mixes. The results were compared to find the optimum TDA content and to study the stress-strain behavior of the mixtures. It was observed that mixing TDA up to 6% by weight with clay significantly changes the shear strength, and the internal friction angle increases from 27.47 to 59.39º (an increase of 46.25%). However, the cohesion significantly decreases from 45 to 26 kPa (a decrease of 57.77%). On the other hand, it was observed that increasing the TDA content reduces the density and increases the shear strength of the mixtures. Also, the addition of TDA increases the mixture consolidation and deformation level at failure.
Preliminary Study of Pleurotus ostreatus (Jacq.) P. Kumm. Spent Mushroom Compost as Nutrient Supplement on the Shoot Induction of Fig Tissue Culture
Authors: Shiekh Mahmud Siti Hamidah Radiyah , Tan Suat Hian , Wan Anuar Wan Nurul Hidayah , Ma Nyuk Ling
Published: August 2022

Spent mushroom compost is identified as waste substrate. As the mushroom agriculture industry is growing rapidly, the production also increases and contributes to large amounts of spent mushroom compost annually. The conversion of spent mushroom compost as waste to wealth is a great concept that can give value to agricultural industry and solid waste management of mushroom cultivation. The use of SMC as nurient supplement may reduce the production cost for in vitro culture of fig plant. This research is to study the use of Pleurotus ostreatus (Jacq.) P. Kumm. spent mushroom compost (SMC) as a nutrient supplement of the media in shoot induction of fig plant. Nodal segment of fig’s stem was cultured in MS media supplemented with different concentrations of SMC. With presence of SMC, 10% SMC have the highest shoot proliferation (2.167 ± 1.169) and length of shoot (0.154 ± 0.060 cm). The study revealed that in presence of 10% of SMC could produce new shoots at a frequency which was comparable to the control (p<0.05; n=3; Tukey’s multiple range test). Among the different media combinations of plant growth regulators with SMC, 15 μM Kinetin with 10% SMC is the most effective treatment which gave maximum number of shoot proliferation (3.00 ± 1.27). 30 μM IAA with 10% SMC media have the highest leaves regenerated which were 1.33 ± 0.84. In conclusion, the SMC added in media for plant tissue culture had positive effect on shoot induction thus highlighted the potential of waste substrate of SMC to act as nutrient supplement for plant tissue culture.
Alkali Impregnation and Steam Explosion of Cogon Grass for Improved Enzymatic Saccharification
Authors: Rivadeneira Joel Padilla , Nayve Jr. Fidel Rey P.
Published: August 2022

Process parameters for the alkali-impregnation of cogon and its combination with steam explosion were evaluated and optimized using Response Surface Modeling (RSM). Dried cogon (10% w/v) was impregnated in diluted base (1, 2, 3% (w/w) NaOH) at different ranges of temperature (50, 85,120 °C) and time (15, 32.5, 50 min), and then subjected to enzymatic saccharification using 60 FPU/g Accelerase 1500TM. The concentration of reducing sugar released was measured using Nelson-Somogyi Colorimetric Method. The RSM showed that the optimum condition, predicting 10% Reducing Sugar Yield (RSY), was treatment of 10 % (w/v) cogon with 1.5% NaOH (w/v) at 73 °C for 15 min. Upon validation, done in triplicates, 13+1.0% RSY was obtained. The optimally-impregnated cogon was subjected to a steam explosion treatment to improve its saccharifiability. The factors varied were temperature (170 to 225 °C) and exposure time (250 to 800 s). Upon saccharification of the steam-exploded samples, the RSM indicated that the best steam explosion condition, predicting 14% RSY, was 225 °C and 800 s. Upon validation, 15+0.5% RSY was obtained. Steam explosion improved the saccharifiability of NaOH-impregnated cogon by 15%.
Hardness and Compressive Strength Evaluation of Dental Composites Containing Biosilica-Encapsulated Healing Liquid
Authors: Wang Sherlyn , Takarini Veni , Putri Rindia Maharani , Asri Lia Amelia Tresna Wulan
Published: August 2022

Tooth cavity is one of the most common dental health problems in Indonesia that can be treated by applying dental fillings. However, dental fillings often experience microcrack and secondary caries. Self-Healing Dental Materials (SHDM) which use microencapsulation technique as healing system, are developed to solve this problem. In this work, we employed mesoporous biosilica from Cyclotella striata TBI as microcapsule to entrap healing liquid contains polyacrylic acid and polybasic carboxylic acid. SHDM was prepared by mixing Filtek Z350XT flowable composite with fluoroaluminosilicate healing powder and healing liquid encapsulated in biosilica. We also added silica containing cetyltrimethyl ammonium bromide (CTAB@PSN) filler as antibacterial agent. Six groups of tested samples were prepared with various composition of biosilica and CTAB@PSN. Filtek composite was used as a control. We studied the entrapment of helaing liquid in biosilica and effect of biosilica addition towards mechanical properties of the resulting SHDM. The statistical analysis was determined using ANOVA. Scanning Electron Microscopy and Fourier Transform Infra-Red showed that the microencapsulation of healing liquid in biosilica was successful with immersion method without stirring. Addition of biosilica and CTAB@PSN fillers into the Filtek composites resulted in the decrease of the mechanical properties. The hardness values of the resulting composites were in the range 44.33–53.25 VHN. Nevertheless, the hardness values were still comparable to the hardness of dentin. Addition of filler decreased the compressive strength, but statistically insignificant, from 268.68 MPa to 228.53–252.04 MPa. To conclude, healing liquid can be entrapped in porous biosilica. Adding healing agent affects SHDM composite’s hardness but not its compressive strength.