Search results for: cluster integration
848 Sensitivity Analysis and Solitary Wave Solutions to the (2+1)-Dimensional Boussinesq Equation in Dispersive Media
Authors: Naila Nasreen, Dianchen Lu
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This paper explores the dynamical behavior of the (2+1)-dimensional Boussinesq equation, which is a nonlinear water wave equation and is used to model wave packets in dispersive media with weak nonlinearity. This equation depicts how long wave made in shallow water propagates due to the influence of gravity. The (2+1)- dimensional Boussinesq equation combines the two-way propagation of the classical Boussinesq equation with the dependence on a second spatial variable, as that occurs in the two-dimensional Kadomstev- Petviashvili equation. This equation provides a description of head- on collision of oblique waves and it possesses some interesting properties. The governing model is discussed by the assistance of Ricatti equation mapping method, a relatively integration tool. The solutions have been extracted in different forms the solitary wave solutions as well as hyperbolic and periodic solutions. Moreover, the sensitivity analysis is demonstrated for the designed dynamical structural system’s wave profiles, where the soliton wave velocity and wave number parameters regulate the water wave singularity. In addition to being helpful for elucidating nonlinear partial differential equations, the method in use gives previously extracted solutions and extracts fresh exact solutions. Assuming the right values for the parameters, various graph in different shapes are sketched to provide information about the visual format of the earned results. This paper’s findings support the efficacy of the approach taken in enhancing nonlinear dynamical behavior. We believe this research will be of interest to a wide variety of engineers that work with engineering models. Findings show the effectiveness simplicity, and generalizability of the chosen computational approach, even when applied to complicated systems in a variety of fields, especially in ocean engineering.Keywords: (2+1)-dimensional Boussinesq equation, solitary wave solutions, Ricatti equation mapping approach, nonlinear phenomena
Procedia PDF Downloads 100847 Reimagining the Management of Telco Supply Chain with Blockchain
Authors: Jeaha Yang, Ahmed Khan, Donna L. Rodela, Mohammed A. Qaudeer
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Traditional supply chain silos still exist today due to the difficulty of establishing trust between various partners and technological barriers across industries. Companies lose opportunities and revenue and inadvertently make poor business decisions resulting in further challenges. Blockchain technology can bring a new level of transparency through sharing information with a distributed ledger in a decentralized manner that creates a basis of trust for business. Blockchain is a loosely coupled, hub-style communication network in which trading partners can work indirectly with each other for simpler integration, but they work together through the orchestration of their supply chain operations under a coherent process that is developed jointly. A Blockchain increases efficiencies, lowers costs, and improves interoperability to strengthen and automate the supply chain management process while all partners share the risk. Blockchain ledger is built to track inventory lifecycle for supply chain transparency and keeps a journal of inventory movement for real-time reconciliation. State design patterns are used to capture the life cycle (behavior) of inventory management as a state machine for a common, transparent and coherent process which creates an opportunity for trading partners to become more responsive in terms of changes or improvements in process, reconcile discrepancies, and comply with internal governance and external regulations. It enables end-to-end, inter-company visibility at the unit level for more accurate demand planning with better insight into order fulfillment and replenishment.Keywords: supply chain management, inventory trace-ability, perpetual inventory system, inventory lifecycle, blockchain, inventory consignment, supply chain transparency, digital thread, demand planning, hyper ledger fabric
Procedia PDF Downloads 90846 The Construct of Personal Choice within Individual Language Shift: A Phenomenological Qualitative Study
Authors: Kira Gulko Morse
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Choosing one’s primary language may not be as common as choosing an additional foreign language to study or use during travel. In some instances, however, it becomes a matter of internal personal struggle, as language is tied not only to specific circumstances but also to human background and identity. This phenomenological qualitative study focuses on the factors affecting the decision of a person to undergo a language shift. Specifically, it considers how these factors relate to identity negotiation and expression. The data for the study include the analysis of published autobiographical narratives and personal interviews conducted using the Responsive Interviewing model. While research participants come from a variety of geographical locations and have used different reasons for undergoing their individual language shift, the study identifies a number of common features shared by all the participants. Specifically, while all the participants have been able to maintain their first language to varying degrees of proficiency, they have all completed the shift to establish a primary language different from their first. Additionally, the process of self-identification is found to be directly connected to the phenomenon of language choice for each of the participants. The findings of the study further tie the phenomenon of individual language shift to a more comprehensive issue of individual life choices – ethnic revival, immigration, and inter-cultural marriage among others. The study discusses varying language roles and the data indicate that language shift may occur whether it is a symbolic driving force or a secondary means in fulfilling a set life goal. The concept of language addition is suggested as an alternative to the arbitrariness of language shift. Thus, instead of focusing on subtractive bilingualism or language loss, the emphasis becomes the integration of languages within the individual. The study emphasizes the importance of the construct of personal choice in its connection to individual language shift. It places the focus from society onto an individual and the ability of an individual to make decisions in matters of linguistic identification.Keywords: choice theory, identity negotiation, language shift, psycholinguistics
Procedia PDF Downloads 135845 Aesthetics of Colours, Symbols, and Spectacles in the 2021 National Festival of Arts and Culture, Ekiti State, Nigeria
Authors: Bade-Afuye Toyin Beatrice
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Nigeria, as a multi-cultural nation, boasts of many festivals, many of which are found in the six geo-political zones of the country. One of the major festivals that bring together the Nigerian citizens as one entity is the National Festival of Arts and Culture (NAFEST), organized by the National Council for Arts and Culture (NCAC). The festival is celebrated yearly in ways that are unique to Nigerians and culture enthusiasts locally and abroad. The festival has equally boosted the Nigerian economy through tourism promotion and culture preservation. This study shall adopt the cultural identity theory. The theory will be used to examine the festival as a platform that showcases culture, which represents the totality of the ways and lives of the Nigerian people. To achieve this, the researcher shall gather data as a participant-observer during the festival, which featured elements such as costume, make-up, dance, drama, children's theatre, fashion parade, local cuisines, local games, music, props, acrobatic displays, trade fair among others. These elements are the cultural aesthetics of the festival, thereby creating spectacles and colours in unique styles by each of the 36 states of the federation and the FCT Abuja. The study particularly examines the 2021 edition of NAFEST hosted by the Ekiti State Government. The study reveals that the festival is a unique multi-ethnic event that brings together Nigerians and their kinsmen in the diaspora. NAFEST has equally provided a good opportunity to showcase the rich cultural heritage of the Ekiti people and the economic values of their products and materials. The paper, therefore, concludes that the National Festival of Arts and Culture has over the years promoted national unity and social integration among Nigerians.Keywords: colours, culture, spectacle, NAFEST
Procedia PDF Downloads 106844 Urban Regeneration of Unplanned Settlements in Al-Ruwais
Authors: Rama Ajineh
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Neighborhoods are defined as local zones within settlements and cities recognized by individuals who live there, with their identities and given boundaries. Neighborhoods mainly structure individual’s lives, the small box which various social groups interact with each other, develop and become one strong entity. Also, it is a platform for more activities, providing many of the social services to enhance the connections between the people, giving a sense of community. However, some of these neighborhoods were unplanned and caused many social, economical and architectural problems to its residents in the first place, and to the city. A great example of such case is in Saudi Arabia, Jeddah, Al-Ruwais neighborhood, where the authority is planning to regenerate the area and make it a landmark for the city. Urban Regeneration of Unplanned Settlements is a process to make people live and work, now and in the future, and meet the various needs of the current and coming inhabitants, with a high-quality life for all. Through research, it was discovered that Urban regeneration plans on Al-Ruwais were planned regardless to the collective agreement of the inhabitants, giving themselves the absolute right to demolish and reconstruct the desired locations with a low compensation. Consequently, a deep research will be done on integrating the residents with the process, by showcasing examples of successful Urban Regenerations of Unplanned settlements in different cities. The research aims to understand the sustainable, and well-planned regeneration strategies used to enhance people’s living without harming them, and give sustainable urban solutions. Moreover, the research explores the definition of Sustainable Communities. The used methods in this paper are secondary research on site analysis and the relationship between the human and the neighborhood. The conclusion reveals the most successful fashion of Urban regeneration of Unplanned settlements and applies it to Al-Ruwais neighborhood considering the human factor as a primary element.Keywords: architecture, human integration, original residents, site analysis, sustainable communities, urban sustainable solutions, urban regeneration
Procedia PDF Downloads 182843 Improving Fake News Detection Using K-means and Support Vector Machine Approaches
Authors: Kasra Majbouri Yazdi, Adel Majbouri Yazdi, Saeid Khodayi, Jingyu Hou, Wanlei Zhou, Saeed Saedy
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Fake news and false information are big challenges of all types of media, especially social media. There is a lot of false information, fake likes, views and duplicated accounts as big social networks such as Facebook and Twitter admitted. Most information appearing on social media is doubtful and in some cases misleading. They need to be detected as soon as possible to avoid a negative impact on society. The dimensions of the fake news datasets are growing rapidly, so to obtain a better result of detecting false information with less computation time and complexity, the dimensions need to be reduced. One of the best techniques of reducing data size is using feature selection method. The aim of this technique is to choose a feature subset from the original set to improve the classification performance. In this paper, a feature selection method is proposed with the integration of K-means clustering and Support Vector Machine (SVM) approaches which work in four steps. First, the similarities between all features are calculated. Then, features are divided into several clusters. Next, the final feature set is selected from all clusters, and finally, fake news is classified based on the final feature subset using the SVM method. The proposed method was evaluated by comparing its performance with other state-of-the-art methods on several specific benchmark datasets and the outcome showed a better classification of false information for our work. The detection performance was improved in two aspects. On the one hand, the detection runtime process decreased, and on the other hand, the classification accuracy increased because of the elimination of redundant features and the reduction of datasets dimensions.Keywords: clustering, fake news detection, feature selection, machine learning, social media, support vector machine
Procedia PDF Downloads 176842 Advancing Spatial Mapping and Monitoring of Illegal Landfills for Deprived Urban Areas in Romania
Authors: ȘercăIanu Mihai, Aldea Mihaela, Iacoboaea Cristina, Luca Oana, Nenciu Ioana
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The emergence and neutralization of illegal waste dumps represent a global concern for waste management ecosystems with a particularly pronounced impact on disadvantaged communities. All over the world, and in this particular case in Romania, a relevant number of people resided in houses lacking any legal forms such as land ownership documents or building permits. These areas are referred to as “informal settlements”. An increasing number of regions and cities in Romania are struggling to manage their waste dumps, especially in the context of increasing poverty and lack of regulation related to informal settlements. An example of such informal settlement can be found at the terminus of Bistra Street in Câlnic, which falls under the jurisdiction of the Municipality of Reșița in Caras Severin County. The article presents a case study that focuses on employing remote sensing techniques and spatial data to monitor and map illegal waste practices, with subsequent integration into a geographic information system tailored for the Reșița community. In addition, the paper outlines the steps involved in devising strategies aimed at enhancing waste management practices in disadvantaged areas, aligning with the shift toward a circular economy. Results presented in the paper contain a spatial mapping and visualization methodology calibrated with in situ data collection applicable for identifying illegal landfills. The emergence and neutralization of illegal dumps pose a challenge in the field of waste management. These approaches, which prove effective where conventional solutions have failed, need to be replicated and adopted more wisely.Keywords: waste dumps, waste management, monitoring, GIS, informal settlements
Procedia PDF Downloads 86841 An Inclusion Project for Deaf Children into a Northern Italy Contest
Authors: G. Tamanza, A. Bossoni
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84 deaf students (from primary school to college) and their families participated in this inclusion project in cooperation with numerous institutions in northern Italy (Brescia-Lombardy). Participants were either congenitally deaf or their deafness was related to other pathologies. This research promoted the integration of deaf students as they pass from primary school to high school to college. Learning methods and processes were studied that focused on encouraging individual autonomy and socialization. The research team and its collaborators included school teachers, speech therapists, psychologists and home tutors, as well as teaching assistants, child neuropsychiatrists and other external authorities involved with deaf persons social inclusion programs. Deaf children and their families were supported, in terms of inclusion, and were made aware of the research team that focused on the Bisogni Educativi Speciali (BES or Special Educational Needs) (L.170/2010 - DM 5669/2011). This project included a diagnostic and evaluative phase as well as an operational one. Results demonstrated that deaf children were highly satisfied and confident; academic performance improved and collaboration in school increased. Deaf children felt that they had access to high school and college. Empowerment for the families of deaf children in terms of networking among local services that deal with the deaf also improved while family satisfaction also improved. We found that teachers and those who gave support to deaf children increased their professional skills. Achieving autonomy, instrumental, communicative and relational abilities were also found to be crucial. Project success was determined by temporal continuity, clear theoretical methodology, strong alliance for the project direction and a resilient team response.Keywords: autonomy, inclusion, skills, well-being
Procedia PDF Downloads 288840 QR Technology to Automate Health Condition Detection in Payment System: A Case Study in the Kingdom of Saudi Arabia’s Schools
Authors: Amjad Alsulami, Farah Albishri, Kholod Alzubidi, Lama Almehemadi, Salma Elhag
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Food allergy is a common and rising problem among children. Many students have their first allergic reaction at school, one of these is anaphylaxis, which can be fatal. This study discovered that several schools' processes lacked safety regulations and information on how to handle allergy issues and chronic diseases like diabetes where students were not supervised or monitored during the cafeteria purchasing process. There is no obvious prevention or effort in academic institutions when purchasing food containing allergens or negatively impacting the health status of students who suffer from chronic diseases. Students must always be stable to reflect positively on their educational development process. To address this issue, this paper uses a business reengineering process to propose the automation of the whole food-purchasing process, which will aid in detecting and avoiding allergic occurrences and preventing any side effects from eating foods that are conflicting with students' health. This may be achieved by designing a smart card with an embedded QR code that reveals which foods cause an allergic reaction in a student. A survey was distributed to determine and examine how the cafeteria will handle allergic children and whether any management or policy is applied in the school. Also, the survey findings indicate that the integration of QR technology into the food purchasing process would improve health condition detection. The suggested system would be beneficial to all parties, the family agreed, as they would ensure that their children didn't eat foods that were bad for their health. Moreover, by analyzing and simulating the as-is process and the suggested process the results demonstrate that there is an improvement in quality and time.Keywords: QR code, smart card, food allergies, business process reengineering, health condition detection
Procedia PDF Downloads 75839 Data Mining Spatial: Unsupervised Classification of Geographic Data
Authors: Chahrazed Zouaoui
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In recent years, the volume of geospatial information is increasing due to the evolution of communication technologies and information, this information is presented often by geographic information systems (GIS) and stored on of spatial databases (BDS). The classical data mining revealed a weakness in knowledge extraction at these enormous amounts of data due to the particularity of these spatial entities, which are characterized by the interdependence between them (1st law of geography). This gave rise to spatial data mining. Spatial data mining is a process of analyzing geographic data, which allows the extraction of knowledge and spatial relationships from geospatial data, including methods of this process we distinguish the monothematic and thematic, geo- Clustering is one of the main tasks of spatial data mining, which is registered in the part of the monothematic method. It includes geo-spatial entities similar in the same class and it affects more dissimilar to the different classes. In other words, maximize intra-class similarity and minimize inter similarity classes. Taking account of the particularity of geo-spatial data. Two approaches to geo-clustering exist, the dynamic processing of data involves applying algorithms designed for the direct treatment of spatial data, and the approach based on the spatial data pre-processing, which consists of applying clustering algorithms classic pre-processed data (by integration of spatial relationships). This approach (based on pre-treatment) is quite complex in different cases, so the search for approximate solutions involves the use of approximation algorithms, including the algorithms we are interested in dedicated approaches (clustering methods for partitioning and methods for density) and approaching bees (biomimetic approach), our study is proposed to design very significant to this problem, using different algorithms for automatically detecting geo-spatial neighborhood in order to implement the method of geo- clustering by pre-treatment, and the application of the bees algorithm to this problem for the first time in the field of geo-spatial.Keywords: mining, GIS, geo-clustering, neighborhood
Procedia PDF Downloads 375838 Implementation of Fuzzy Version of Block Backward Differentiation Formulas for Solving Fuzzy Differential Equations
Authors: Z. B. Ibrahim, N. Ismail, K. I. Othman
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Fuzzy Differential Equations (FDEs) play an important role in modelling many real life phenomena. The FDEs are used to model the behaviour of the problems that are subjected to uncertainty, vague or imprecise information that constantly arise in mathematical models in various branches of science and engineering. These uncertainties have to be taken into account in order to obtain a more realistic model and many of these models are often difficult and sometimes impossible to obtain the analytic solutions. Thus, many authors have attempted to extend or modified the existing numerical methods developed for solving Ordinary Differential Equations (ODEs) into fuzzy version in order to suit for solving the FDEs. Therefore, in this paper, we proposed the development of a fuzzy version of three-point block method based on Block Backward Differentiation Formulas (FBBDF) for the numerical solution of first order FDEs. The three-point block FBBDF method are implemented in uniform step size produces three new approximations simultaneously at each integration step using the same back values. Newton iteration of the FBBDF is formulated and the implementation is based on the predictor and corrector formulas in the PECE mode. For greater efficiency of the block method, the coefficients of the FBBDF are stored at the start of the program. The proposed FBBDF is validated through numerical results on some standard problems found in the literature and comparisons are made with the existing fuzzy version of the Modified Simpson and Euler methods in terms of the accuracy of the approximated solutions. The numerical results show that the FBBDF method performs better in terms of accuracy when compared to the Euler method when solving the FDEs.Keywords: block, backward differentiation formulas, first order, fuzzy differential equations
Procedia PDF Downloads 319837 Spirituality Enhanced with Cognitive-Behavioural Techniques: An Effective Method for Women with Extramarital Infidelity: A Literature Review
Authors: Setareh Yousife
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Introduction: Studies suggest that Extramarital Infidelity (EMI) variants, such as sexual and emotional infidelities are increasing in marriage relationships. To our knowledge, less is known about what therapies and mental-hygiene factors can prevent more effective this behavior and address it. Spiritual and cognitive-behavioural health have proven to reduce marital conflict, Increase marital satisfaction and commitment. Objective: This study aims to discuss the effectiveness of spiritual counseling combined with Cognitive-behavioural techniques in addressing Extramarital Infidelity. Method: Descriptive, analytical, and intervention articles indexed in SID, Noormags, Scopus, Iranmedex, Web of Science and PubMed databases, and Google Scholar were searched. We focused on Studies in which Women with extramarital relationships, including heterosexual married couples-only studies and spirituality/religion and CBT as coping techniques used as EMI therapy. Finally, the full text of all eligible articles was prepared and discussed in this review. Results: 25 publications were identified, and their textual analysis facilitated through four thematic approaches: The nature of EMI in Women, the meaning of spirituality in the context of mental health and human behavior as well as psychotherapy; Spirituality integrated into Cognitive-Behavioral approach, The role of Spirituality as a deterrent to EMI. Conclusions: The integration of the findings discussed herein suggests that the application of cognitive and behavioral skills in addressing these kinds of destructive family-based relationships is inevitable. As treatments based on religion/spirituality or cognition/behavior do not seem adequately effective in dealing with EMI, the combination of these approaches may lead to higher efficacy in fewer sessions and a shorter time.Keywords: spirituality, religion, cognitive behavioral therapy, extramarital relation, infidelity
Procedia PDF Downloads 254836 Newly Designed Ecological Task to Assess Cognitive Map Reading Ability: Behavioral Neuro-Anatomic Correlates of Mental Navigation
Authors: Igor Faulmann, Arnaud Saj, Roland Maurer
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Spatial cognition consists in a plethora of high level cognitive abilities: among them, the ability to learn and to navigate in large scale environments is probably one of the most complex skills. Navigation is thought to rely on the ability to read a cognitive map, defined as an allocentric representation of ones environment. Those representations are of course intimately related to the two geometrical primitives of the environment: distance and direction. Also, many recent studies point to a predominant hippocampal and para-hippocampal role in spatial cognition, as well as in the more specific cluster of navigational skills. In a previous study in humans, we used a newly validated test assessing cognitive map processing by evaluating the ability to judge relative distances and directions: the CMRT (Cognitive Map Recall Test). This study identified in topographically disorientated patients (1) behavioral differences between the evaluation of distances and of directions, and (2) distinct causality patterns assessed via VLSM (i.e., distinct cerebral lesions cause distinct response patterns depending on the modality (distance vs direction questions). Thus, we hypothesized that: (1) if the CMRT really taps into the same resources as real navigation, there would be hippocampal, parahippocampal, and parietal activation, and (2) there exists underlying neuroanatomical and functional differences between the processing of this two modalities. Aiming toward a better understanding of the neuroanatomical correlates of the CMRT in humans, and more generally toward a better understanding of how the brain processes the cognitive map, we adapted the CMRT as an fMRI procedure. 23 healthy subjects (11 women, 12 men), all living in Geneva for at least 2 years, underwent the CMRT in fMRI. Results show, for distance and direction taken together, than the most active brain regions are the parietal, frontal and cerebellar parts. Additionally, and as expected, patterns of brain activation differ when comparing the two modalities. Furthermore, distance processing seems to rely more on parietal regions (compared to other brain regions in the same modality and also to direction). It is interesting to notice that no significant activity was observed in the hippocampal or parahippocampal areas. Direction processing seems to tap more into frontal and cerebellar brain regions (compared to other brain regions in the same modality and also to distance). Significant hippocampal and parahippocampal activity has been shown only in this modality. This results demonstrated a complex interaction of structures which are compatible with response patterns observed in other navigational tasks, thus showing that the CMRT taps at least partially into the same brain resources as real navigation. Additionally, differences between the processing of distances and directions leads to the conclusion that the human brain processes each modality distinctly. Further research should focus on the dynamics of this processing, allowing a clearer understanding between the two sub-processes.Keywords: cognitive map, navigation, fMRI, spatial cognition
Procedia PDF Downloads 294835 Design and Fabrication of Stiffness Reduced Metallic Locking Compression Plates through Topology Optimization and Additive Manufacturing
Authors: Abdulsalam A. Al-Tamimi, Chris Peach, Paulo Rui Fernandes, Paulo J. Bartolo
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Bone fixation implants currently used to treat traumatic fractured bones and to promote fracture healing are built with biocompatible metallic materials such as stainless steel, cobalt chromium and titanium and its alloys (e.g., CoCrMo and Ti6Al4V). The noticeable stiffness mismatch between current metallic implants and host bone associates with negative outcomes such as stress shielding which causes bone loss and implant loosening leading to deficient fracture treatment. This paper, part of a major research program to design the next generation of bone fixation implants, describes the combined use of three-dimensional (3D) topology optimization (TO) and additive manufacturing powder bed technology (Electron Beam Melting) to redesign and fabricate the plates based on the current standard one (i.e., locking compression plate). Topology optimization is applied with an objective function to maximize the stiffness and constraint by volume reductions (i.e., 25-75%) in order to obtain optimized implant designs with reduced stress shielding phenomenon, under different boundary conditions (i.e., tension, bending, torsion and combined loads). The stiffness of the original and optimised plates are assessed through a finite-element study. The TO results showed actual reduction in the stiffness for most of the plates due to the critical values of volume reduction. Additionally, the optimized plates fabricated using powder bed techniques proved that the integration between the TO and additive manufacturing presents the capability of producing stiff reduced plates with acceptable tolerances.Keywords: additive manufacturing, locking compression plate, finite element, topology optimization
Procedia PDF Downloads 198834 Using the Theory of Reasoned Action and Parental Mediation Theory to Examine Cyberbullying Perpetration among Children and Adolescents
Authors: Shirley S. Ho
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The advancement and development of social media have inadvertently brought about a new form of bullying – cyberbullying – that transcends across physical boundaries of space. Although extensive research has been conducted in the field of cyberbullying, most of these studies have taken an overwhelmingly empirical angle. Theories guiding cyberbullying research are few. Furthermore, very few studies have explored the association between parental mediation and cyberbullying, with majority of existing studies focusing on cyberbullying victimization rather than perpetration. Therefore, this present study investigates cyberbullying perpetration from a theoretical angle, with a focus on the Theory of Reasoned Action and the Parental Mediation Theory. More specifically, this study examines the direct effects of attitude, subjective norms, descriptive norms, injunctive norms and active mediation and restrictive mediation on cyberbullying perpetration on social media among children and adolescents in Singapore. Furthermore, the moderating role of age on the relationship between parental mediation and cyberbullying perpetration on social media are examined. A self-administered paper-and-pencil nationally-representative survey was conducted. Multi-stage cluster random sampling was used to ensure that schools from all the four (North, South, East, and West) regions of Singapore were equally represented in the sample used for the survey. In all 607 upper primary school children (i.e., Primary 4 to 6 students) and 782 secondary school adolescents participated in our survey. The total average response rates were 69.6% for student participation. An ordinary least squares hierarchical regression analysis was conducted to test the hypotheses and research questions. The results revealed that attitude and subjective norms were positively associated with cyberbullying perpetration on social media. Descriptive norms and injunctive norms were not found to be significantly associated with cyberbullying perpetration. The results also showed that both parental mediation strategies were negatively associated with cyberbullying perpetration on social media. Age was a significant moderator of both parental mediation strategies and cyberbullying perpetration. The negative relationship between active mediation and cyberbullying perpetration was found to be greater in the case of children than adolescents. Children who received high restrictive parental mediation were less likely to perform cyberbullying behaviors, while adolescents who received high restrictive parental mediation were more likely to be engaged in cyberbullying perpetration. The study reveals that parents should apply active mediation and restrictive mediation in different ways for children and adolescents when trying to prevent cyberbullying perpetration. The effectiveness of active parental mediation for reducing cyberbullying perpetration was more in the case of children than for adolescents. Younger children were found to be more likely to respond more positively toward restrictive parental mediation strategies, but in the case of adolescents, overly restrictive control was found to increase cyberbullying perpetration. Adolescents exhibited less cyberbullying behaviors when under low restrictive strategies. Findings highlight that the Theory of Reasoned Action and Parental Mediation Theory are promising frameworks to apply in the examination of cyberbullying perpetration. The findings that different parental mediation strategies had differing effectiveness, based on the children’s age, bring about several practical implications that may benefit educators and parents when addressing their children’s online risk.Keywords: cyberbullying perpetration, theory of reasoned action, parental mediation, social media, Singapore
Procedia PDF Downloads 252833 Accounting Propositions for Sustainability Performance Information Systems Introduction: Environmental Attributes from Croatian Hotels
Authors: Vanja Vejzagic, Jackie Brander Brown, Peter Schmidt
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Purpose: For some time now, the global hotel industry trends are strongly oriented towards sustainable development and environmental management accounting (EMA) should have the supporting role for hotel’s corporate social responsibility (CSR) management. The aim of this paper is thus to analyse and present data on the key steps leading toward the effective incorporation of EMA within hotel performance information systems. Design/Methodology/Approach: The research study is a continuation of the process carried out on the sample of 20 eco-hotels in the UK, a year ago. Research evidence was obtained via in-depth case studies on sample of 180 hotels (4 and 5 stars hotels) located in Croatia. Research was conducted through interviews with key personnel and an online survey which specifically focused on 10 business areas considered vital for successful EMA integration. Findings: The research results indicate a pattern by which hotels can determine the existing level of their sustainable (environmental) business. Furthermore, the management understanding of the sustainability concept was still proven to lead to a relatively subjective appreciation and presentation of sustainable hotel operations and their performance. It was determined that majority of analysed hotel organisations reflect typical short-term, financially oriented performance information systems. Steps for EMA introduction have been offered. Research Limitations/Implications: CSR is still a broad-set concept. Exploring the effects of EMA on such-like a defined management system may be subject to considerable influence of the respondent’s subjective perception of the concept. Originality/Value: This article should be of interest to higher education academics and careers staff who have an interest in CSR introduction and the ways of implementing its informational support for performance measurement.Keywords: environmental management accounting, EMA, corporate social responsibility, CSR, sustainability, hotel
Procedia PDF Downloads 174832 Flood Mapping and Inoudation on Weira River Watershed (in the Case of Hadiya Zone, Shashogo Woreda)
Authors: Alilu Getahun Sulito
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Exceptional floods are now prevalent in many places in Ethiopia, resulting in a large number of human deaths and property destruction. Lake Boyo watershed, in particular, had also traditionally been vulnerable to flash floods throughout the Boyo watershed. The goal of this research is to create flood and inundation maps for the Boyo Catchment. The integration of Geographic information system(GIS) technology and the hydraulic model (HEC-RAS) were utilized as methods to attain the objective. The peak discharge was determined using Fuller empirical methodology for intervals of 5, 10, 15, and 25 years, and the results were 103.2 m3/s, 158 m3/s, 222 m3/s, and 252 m3/s, respectively. River geometry, boundary conditions, manning's n value of varying land cover, and peak discharge at various return periods were all entered into HEC-RAS, and then an unsteady flow study was performed. The results of the unsteady flow study demonstrate that the water surface elevation in the longitudinal profile rises as the different periods increase. The flood inundation charts clearly show that regions on the right and left sides of the river with the greatest flood coverage were 15.418 km2 and 5.29 km2, respectively, flooded by 10,20,30, and 50 years. High water depths typically occur along the main channel and progressively spread to the floodplains. The latest study also found that flood-prone areas were disproportionately affected on the river's right bank. As a result, combining GIS with hydraulic modelling to create a flood inundation map is a viable solution. The findings of this study can be used to care again for the right bank of a Boyo River catchment near the Boyo Lake kebeles, according to the conclusion. Furthermore, it is critical to promote an early warning system in the kebeles so that people can be evacuated before a flood calamity happens. Keywords: Flood, Weira River, Boyo, GIS, HEC- GEORAS, HEC- RAS, Inundation MappingKeywords: Weira River, Boyo, GIS, HEC- GEORAS, HEC- RAS, Inundation Mapping
Procedia PDF Downloads 47831 Simplified INS\GPS Integration Algorithm in Land Vehicle Navigation
Authors: Othman Maklouf, Abdunnaser Tresh
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Land vehicle navigation is subject of great interest today. Global Positioning System (GPS) is the main navigation system for positioning in such systems. GPS alone is incapable of providing continuous and reliable positioning, because of its inherent dependency on external electromagnetic signals. Inertial Navigation (INS) is the implementation of inertial sensors to determine the position and orientation of a vehicle. The availability of low-cost Micro-Electro-Mechanical-System (MEMS) inertial sensors is now making it feasible to develop INS using an inertial measurement unit (IMU). INS has unbounded error growth since the error accumulates at each step. Usually, GPS and INS are integrated with a loosely coupled scheme. With the development of low-cost, MEMS inertial sensors and GPS technology, integrated INS/GPS systems are beginning to meet the growing demands of lower cost, smaller size, and seamless navigation solutions for land vehicles. Although MEMS inertial sensors are very inexpensive compared to conventional sensors, their cost (especially MEMS gyros) is still not acceptable for many low-end civilian applications (for example, commercial car navigation or personal location systems). An efficient way to reduce the expense of these systems is to reduce the number of gyros and accelerometers, therefore, to use a partial IMU (ParIMU) configuration. For land vehicular use, the most important gyroscope is the vertical gyro that senses the heading of the vehicle and two horizontal accelerometers for determining the velocity of the vehicle. This paper presents a field experiment for a low-cost strap down (ParIMU)\GPS combination, with data post processing for the determination of 2-D components of position (trajectory), velocity and heading. In the present approach, we have neglected earth rotation and gravity variations, because of the poor gyroscope sensitivities of our low-cost IMU (Inertial Measurement Unit) and because of the relatively small area of the trajectory.Keywords: GPS, IMU, Kalman filter, materials engineering
Procedia PDF Downloads 422830 Plural Perspectives in Conservation Conflicts: The Role of Iconic Species
Authors: Jean Hugé, Francisco Benitez-Capistros, Giorgia Camperio-Ciani
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Addressing conservation conflicts requires the consideration of multiple stakeholders' perspectives and knowledge claims, in order to inform complex and possibly contentious decision-making dilemmas. Hence, a better understanding of why people in particular contexts act in a particular way in a conservation conflict is needed. First, this contribution aims at providing and applying an approach to map and interpret the diversity of subjective viewpoints with regard to iconic species in conservation conflicts. Secondly, this contribution aims to feed the reflection on the possible consequences of the diversity of perspectives for the future management of wildlife (in particular iconic species), based on case studies in Galapagos and Malaysia. The use of the semi-quantitative Q methodology allowed us to identify various perspectives on conservation in different social-ecological contexts. While the presence of iconic species may lead to a more passionate and emotional debate, it may also provide more opportunities for finding common ground and for jointly developing acceptable management solutions that will depolarize emergent, long-lasting or latent conservation conflicts. Based on the research team’s experience in the field, and on the integration of ecological and social knowledge, methodological and management recommendations are made with regard to conservation conflicts involving iconic wildlife. The mere presence of iconic wildlife does not guarantee its centrality in conservation conflicts, and comparisons will be drawn between the cases of the giant tortoises (Chelonoidis spec.) in Galapagos, Ecuador and the Milky Stork (Mycteria cinerea) in western peninsular Malaysia. Acknowledging the diversity of viewpoints, reflecting how different stakeholders see, act and talk about wildlife management, highlights the need to develop pro-active and resilient strategies to deal with these issues.Keywords: conservation conflicts, Q methodology, Galapagos, Malaysia, giant tortoise, milky stork
Procedia PDF Downloads 284829 A Comparative Analysis: Cultural Reflections of Mexicans in the United States and Turks in Germany
Authors: Gülşen Kocaevli
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This paper aims to conduct a comparative analysis on the reflections of cultural elements such as language, festival, and food both in the case of Turkish immigrants in Germany and Mexican immigrants in the United States within a historical perspective. These reflections will be studied first by giving a certain background information on the migratory history of the two nations, Mexican immigration to the US, and Turkish immigration to Germany, respectively. These two cases were picked as the analytical subjects of this paper because both nations first migrated to the related country to constitute a labor force since there was a huge need for that due to several reasons such as the loss of manpower after certain wars or revolutions. At the end of this comparative study, it is speculated to be found that there are certain parallels between these two immigrant societies in the way that they reflect their cultures in the receiving country since both nations have a conventionalist nature which makes them tend more to protect their cultures and pay less effort to integrate into the society in which they are living. Even though this integration might be realized in certain fields like economic status and exogamy, it does not cover all segments nor is there any desire of the receiving government to integrate the immigrants but rather they make policies to assimilate them. This research paper will use a qualitative method which is fundamentally based on the interpretative data drawn from several sociological or ethnographic studies conducted in the related field. The primary and secondary resources of this paper will cover academic books, journal articles, particularly those reporting interviews with the immigrants, and certain governmental documents as well as publicized statistics regarding the subject of analysis. By the use of the aforementioned methodology and resources, the conventionalist nature of the two immigrant nations is aimed to be presented as the unifying factor in the way that Mexicans in the US and Turks in Germany reflect and protect their cultures in the form of language, festivals, and food.Keywords: assimilation, culture, German-Turks, immigration, Mexican Americans
Procedia PDF Downloads 170828 Functional Switching of Serratia marcescens Transcriptional Regulator from Activator to Inhibitor of Quorum Sensing by Exogenous Addition
Authors: Norihiro Kato, Yuriko Takayama
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Some gram-negative bacteria enable the simultaneous activation of gene expression involved in N-acylhomoserine lactone (AHL) dependent cell-to-cell communication system. Such regulatory system for the bacterial group behavior is termed as quorum sensing (QS) because a diffusible AHL signal can accumulate around the cell during the increase of the cell density and trigger activation of the sequential QS process. By blocking the QS, the expression of diverse genes related to infection, antibiotic production, and biofilm formation is inhibited. Conditioning of QS by regulation of the DNA-receptor-AHL interaction is a potential target for enhancing host defenses against pathogenicity. We focused on engineered application of transcriptional regulator SpnR produced in opportunistic human pathogen Serratia marcescens. The SpnR can interact with AHL signals at an N-terminal domain and also with a promoter region of a QS target gene at a C-terminal domain. As the initial process of the QS activation, the SpnR forms a complex with the AHL to enhance the expression of pig cluster; the SpnR normally acts as an activator for the expression of the QS-dependent gene. In this research, we attempt to artificially control QS by changing the role of SpnR. The QS-dependent prodigiosin production is expected to inhibit by externally added SpnR in the culture broth of AS-1 strain because the AHL concentration was kept below the threshold by AHL-SpnR complex formation. Maltose-binding protein (MBP)-tagged SpnR (MBP-SpnR) was overexpressed in Escherichia coli and purified using an affinity chromatography equipped with an amylose resin column. The specific interaction between AHL and MBP-SpnR was demonstrated by quartz crystal microbalance (QCM) sensor. AHL with amino end-group was coupled with COOH-terminated self-assembled monolayer prepared on a gold electrode of 27-MHz quartz crystal sensor using water-soluble carbodiimide. After the injection of MBP-SpnR into a cup-type sensor cell filled with the buffer solution, time course of resonant frequency change (ΔFs) was determined. A decrease of ΔFs clearly showed the uptake of MBP-SpnR onto the AHL-immobilized electrode. Furthermore, no binding affinity was observed after the heat-inactivation of MBP-SpnR at 80ºC. These results suggest that MBP-SpnR possesses a specific affinity for AHL. MBP-SpnR was added to the culture medium as an AHL trap to study inhibitory effects on intracellularly accumulated prodigiosin. With approximately 2 µM MBP-SpnR, the amount of prodigiosin induced was half that of the control without any additives. In conclusion, the function of SpnR could be switched by adding it to the cell culture. Exogenously added MBP-SpnR possesses high affinity for AHL derived from cells and acts as an inhibitor of AHL-mediated QS.Keywords: intracellular signaling, microbial biotechnology, quorum sensing, transcriptional regulator
Procedia PDF Downloads 267827 Regeneration Study on the Athens City Center: Transformation of the Historical Triangle to “Low Pollution and Restricted Vehicle Traffic Zone”
Authors: Chondrogianni Dimitra, Yorgos J. Stephanedes
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The impact of the economic crisis, coupled with the aging of the city's old core, is reflected in central Athens. Public and private users, residents, employees, visitors desire the quality upgrading of abandoned buildings and public spaces through environmental upgrading and sustainable mobility, and promotion of the international metropolitan character of the city. In the study, a strategy for reshaping the character and function of the historic Athenian triangle is proposed, aiming at its economic, environmental, and social sustainable development through feasible, meaningful, and non-landscaping solutions of low cost and high positive impact. Sustainable mobility is the main principle in re-planning the study area and transforming it into a “Low Pollution and Limited Vehicle Traffic Zone” is the main strategy. Τhe proposed measures include the development of pedestrian mobility networks by expanding the pedestrian roads and limited-traffic routes, of bicycle networks based on the approved Metropolitan Bicycle Route of Athens, of public transportation networks with new lines of electric mini-buses, and of new regulations for vehicle mobility in the historic triangle. In addition, complementary actions are proposed regarding the provision of Wi-Fi on fixed track media, development of applications that facilitate combined travel and provide real-time data, integration of micromobility (roller skates, Segway, Hoverboard), and its enhancement as a flexible means of personal mobility, and development of car-sharing, ride-sharing and dynamic carpooling initiatives.Keywords: regeneration plans, sustainable mobility, environmental upgrading, athens historical triangle
Procedia PDF Downloads 167826 Integrative Biology Teaching and Learning Model Based on STEM Education
Authors: Narupot Putwattana
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Changes in global situation such as environmental and economic crisis brought the new perspective for science education called integrative biology. STEM has been increasingly mentioned for several educational researches as the approach which combines the concept in Science (S), Technology (T), Engineering (E) and Mathematics (M) to apply in teaching and learning process so as to strengthen the 21st-century skills such as creativity and critical thinking. Recent studies demonstrated STEM as the pedagogy which described the engineering process along with the science classroom activities. So far, pedagogical contents for STEM explaining the content in biology have been scarce. A qualitative literature review was conducted so as to gather the articles based on electronic databases (google scholar). STEM education, engineering design, teaching and learning of biology were used as main keywords to find out researches involving with the application of STEM in biology teaching and learning process. All articles were analyzed to obtain appropriate teaching and learning model that unify the core concept of biology. The synthesized model comprised of engineering design, inquiry-based learning, biological prototype and biologically-inspired design (BID). STEM content and context integration were used as the theoretical framework to create the integrative biology instructional model for STEM education. Several disciplines contents such as biology, engineering, and technology were regarded for inquiry-based learning to build biological prototype. Direct and indirect integrations were used to provide the knowledge into the biology related STEM strategy. Meanwhile, engineering design and BID showed the occupational context for engineer and biologist. Technological and mathematical aspects were required to be inspected in terms of co-teaching method. Lastly, other variables such as critical thinking and problem-solving skills should be more considered in the further researches.Keywords: biomimicry, engineering approach, STEM education, teaching and learning model
Procedia PDF Downloads 255825 Creating Database and Building 3D Geological Models: A Case Study on Bac Ai Pumped Storage Hydropower Project
Authors: Nguyen Chi Quang, Nguyen Duong Tri Nguyen
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This article is the first step to research and outline the structure of the geotechnical database in the geological survey of a power project; in the context of this report creating the database that has been carried out for the Bac Ai pumped storage hydropower project. For the purpose of providing a method of organizing and storing geological and topographic survey data and experimental results in a spatial database, the RockWorks software is used to bring optimal efficiency in the process of exploiting, using, and analyzing data in service of the design work in the power engineering consulting. Three-dimensional (3D) geotechnical models are created from the survey data: such as stratigraphy, lithology, porosity, etc. The results of the 3D geotechnical model in the case of Bac Ai pumped storage hydropower project include six closely stacked stratigraphic formations by Horizons method, whereas modeling of engineering geological parameters is performed by geostatistical methods. The accuracy and reliability assessments are tested through error statistics, empirical evaluation, and expert methods. The three-dimensional model analysis allows better visualization of volumetric calculations, excavation and backfilling of the lake area, tunneling of power pipelines, and calculation of on-site construction material reserves. In general, the application of engineering geological modeling makes the design work more intuitive and comprehensive, helping construction designers better identify and offer the most optimal design solutions for the project. The database always ensures the update and synchronization, as well as enables 3D modeling of geological and topographic data to integrate with the designed data according to the building information modeling. This is also the base platform for BIM & GIS integration.Keywords: database, engineering geology, 3D Model, RockWorks, Bac Ai pumped storage hydropower project
Procedia PDF Downloads 167824 Organization of the Purchasing Function for Innovation
Authors: Jasna Prester, Ivana Rašić Bakarić, Božidar Matijević
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Various prominent scholars and substantial practitioner-oriented literature on innovation orientation have shown positive effects on firm performance. There is a myriad of factors that influence and enhance innovation but it has been found in the literature that new product innovations accounted for an average of 14 percent of sales revenues for all firms. If there is one thing that has changed in innovation management during the last decade, it is the growing reliance on external partners. As a consequence, a new task for purchasing arises, as firms need to understand which suppliers actually do have high potential contributing to the innovativeness of the firm and which do not. Purchasing function in an organization is extremely important as it deals on an average of 50% or more of a firm's expenditures. In the nineties the purchasing department was largely seen as a transaction-oriented, clerical function but today purchasing integration provides a formal interface mechanism between purchasing and other firm functions that services other functions within the company. Purchasing function has to be organized differently to enable firm innovation potential. However, innovations are inherently risky. There are behavioral risk (that some partner will take advantage of the other party), technological risk in terms of complexity of products and processes of manufacturing and incoming materials and finally market risks, which in fact judge the value of the innovation. These risks are investigated in this work since it has been found in the literature that the higher the technological risk, higher will be the centralization of the purchasing function as an interface with other supply chain members. Most researches on organization of purchasing function were done by case study analysis of innovative firms. This work actually tends to prove or discard results found in the literature based on case study method. A large data set of 1493 companies, from 25 countries collected in the GMRG 4 survey served as a basis for analysis.Keywords: purchasing function organization, innovation, technological risk, GMRG 4 survey
Procedia PDF Downloads 482823 Competitor Integration with Voice of Customer Ratings in QFD Studies Using Geometric Mean Based on AHP
Authors: Zafar Iqbal, Nigel P. Grigg, K. Govindaraju, Nicola M. Campbell-Allen
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Quality Function Deployment (QFD) is structured approach. It has been used to improve the quality of products and process in a wide range of fields. Using this systematic tool, practitioners normally rank Voice of Customer ratings (VoCs) in order to produce Improvement Ratios (IRs) which become the basis for prioritising process / product design or improvement activities. In one matrix of the House of Quality (HOQ) competitors are rated. The method of obtaining improvement ratios (IRs) does not always integrate the competitors’ rating in a systematic way that fully utilises competitor rating information. This can have the effect of diverting QFD practitioners’ attention from a potentially important VOC to less important VOC. In order to enhance QFD analysis, we present a more systematic method for integrating competitor ratings, utilising the geometric mean of the customer rating matrix. In this paper we develop a new approach, based on the Analytic Hierarchy Process (AHP), in which we generating a matrix of multiple comparisons of all competitors, and derive a geometric mean for each competitor. For each VOC an improved IR is derived which-we argue herein - enhances the initial VOC importance ratings by integrating more information about competitor performance. In this way, our method can help overcome one of the possible shortcomings of QFD. We then use a published QFD example from literature as a case study to demonstrate the use of the new AHP-based IRs, and show how these can be used to re-rank existing VOCs to -arguably- better achieve the goal of customer satisfaction in relation VOC ratings and competitors’ rankings. We demonstrate how two dimensional AHP-based geometric mean derived from the multiple competitor comparisons matrix can be useful for analysing competitors’ rankings. Our method utilises an established methodology (AHP) applied within an established application (QFD), but in an original way (through the competitor analysis matrix), to achieve a novel improvement.Keywords: quality function deployment, geometric mean, improvement ratio, AHP, competitors ratings
Procedia PDF Downloads 368822 Effectiveness of Breathing Training Program on Quality of Life and Depression Among Hemodialysis Patients: Quasi‐Experimental Study
Authors: Hayfa Almutary, Noof Eid Al Shammari
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Aim: The management of depression in patients undergoing hemodialysis remains challenging. The aim of this study was to evaluate the effectiveness of a breathing training program on quality of life and depression among patients on hemodialysis. Design: A one-group pretest-posttest quasi-experimental design was used. Methods: Data were collected from hemodialysis units at three dialysis centers. Initial baseline data were collected, and a breathing training program was implemented. The breathing training program included three types of breathing exercises. The impact of the intervention on outcomes was measured using both the Kidney Disease Quality of Life Short Version and the Beck Depression Inventory-Second Edition from the same participants. The participants were asked to perform the breathing training program three times a day for 30 days. Results: The mean age of the patients was 52.1 (SD:15.0), with nearly two-thirds of them being male (63.4%). Participants who were undergoing hemodialysis for 1–4 years constituted the largest number of the sample (46.3%), and 17.1% of participants had visited a psychiatric clinic 1-3 times. The results show that the breathing training program improved overall quality of life and reduced symptoms and problems. In addition, a significant decrease in the overall depression score was observed after implementing the intervention. Conclusions: The breathing training program is a non-pharmacological intervention that has proven visible effectiveness in hemodialysis. This study demonstrated that using breathing exercises reduced depression levels and improved quality of life. The integration of this intervention in dialysis units to manage psychological issues will offer a simple, safe, easy, and inexpensive intervention. Future research should compare the effectiveness of various breathing exercises in hemodialysis patients using longitudinal studies. Impact: As a safety precaution, nurses should initially use non-pharmacological interventions, such as a breathing training program, to treat depression in those undergoing hemodialysis.Keywords: breathing training program, depression, exercise, quality of life, hemodialysis
Procedia PDF Downloads 86821 Performance Evaluation of a Very High-Resolution Satellite Telescope
Authors: Walid A. Attia, Taher M. Bazan, Fawzy Eltohamy, Mahmoud Fathy
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System performance evaluation is an essential stage in the design of high-resolution satellite telescopes prior to the development process. In this paper, a system performance evaluation of a very high-resolution satellite telescope is investigated. The evaluated system has a Korsch optical scheme design. This design has been discussed in another paper with respect to three-mirror anastigmat (TMA) scheme design and the former configuration showed better results. The investigated system is based on the Korsch optical design integrated with a time-delay and integration charge coupled device (TDI-CCD) sensor to achieve a ground sampling distance (GSD) of 25 cm. The key performance metrics considered are the spatial resolution, the signal to noise ratio (SNR) and the total modulation transfer function (MTF) of the system. In addition, the national image interpretability rating scale (NIIRS) metric is assessed to predict the image quality according to the modified general image quality equation (GIQE). Based on the orbital, optical and detector parameters, the estimated GSD is found to be 25 cm. The SNR has been analyzed at different illumination conditions of target albedos, sun and sensor angles. The system MTF has been computed including diffraction, aberration, optical manufacturing, smear and detector sampling as the main contributors for evaluation the MTF. Finally, the system performance evaluation results show that the computed MTF value is found to be around 0.08 at the Nyquist frequency, the SNR value was found to be 130 at albedo 0.2 with a nadir viewing angles and the predicted NIIRS is in the order of 6.5 which implies a very good system image quality.Keywords: modulation transfer function, national image interpretability rating scale, signal to noise ratio, satellite telescope performance evaluation
Procedia PDF Downloads 384820 Integration of Polarization States and Color Multiplexing through a Singular Metasurface
Authors: Tarik Sipahi
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Photonics research continues to push the boundaries of optical science, and the development of metasurface technology has emerged as a transformative force in this domain. The work presents the intricacies of a unified metasurface design tailored for efficient polarization and color control in optical systems. The proposed unified metasurface serves as a singular, nanoengineered optical element capable of simultaneous polarization modulation and color encoding. Leveraging principles from metamaterials and nanophotonics, this design allows for unprecedented control over the behavior of light at the subwavelength scale. The metasurface's spatially varying architecture enables seamless manipulation of both polarization states and color wavelengths, paving the way for a paradigm shift in optical system design. The advantages of this unified metasurface are diverse and impactful. By consolidating functions that traditionally require multiple optical components, the design streamlines optical systems, reducing complexity and enhancing overall efficiency. This approach is particularly promising for applications where compactness, weight considerations, and multifunctionality are crucial. Furthermore, the proposed unified metasurface design not only enhances multifunctionality but also addresses key challenges in optical system design, offering a versatile solution for applications demanding compactness and lightweight structures. The metasurface's capability to simultaneously manipulate polarization and color opens new possibilities in diverse technological fields. The research contributes to the evolution of optical science by showcasing the transformative potential of metasurface technology, emphasizing its role in reshaping the landscape of optical system architectures. This work represents a significant step forward in the ongoing pursuit of pushing the boundaries of photonics, providing a foundation for future innovations in compact and efficient optical devices.Keywords: metasurface, nanophotonics, optical system design, polarization control
Procedia PDF Downloads 53819 Infrared Photodetectors Based on Nanowire Arrays: Towards Far Infrared Region
Authors: Mohammad Karimi, Magnus Heurlin, Lars Samuelson, Magnus Borgstrom, Hakan Pettersson
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Nanowire semiconductors are promising candidates for optoelectronic applications such as solar cells, photodetectors and lasers due to their quasi-1D geometry and large surface to volume ratio. The functional wavelength range of NW-based detectors is typically limited to the visible/near-infrared region. In this work, we present electrical and optical properties of IR photodetectors based on large square millimeter ensembles (>1million) of vertically processed semiconductor heterostructure nanowires (NWs) grown on InP substrates which operate in longer wavelengths. InP NWs comprising single or multiple (20) InAs/InAsP QDics axially embedded in an n-i-n geometry, have been grown on InP substrates using metal organic vapor phase epitaxy (MOVPE). The NWs are contacted in vertical direction by atomic layer deposition (ALD) deposition of 50 nm SiO2 as an insulating layer followed by sputtering of indium tin oxide (ITO) and evaporation of Ti and Au as top contact layer. In order to extend the sensitivity range to the mid-wavelength and long-wavelength regions, the intersubband transition within conduction band of InAsP QDisc is suggested. We present first experimental indications of intersubband photocurrent in NW geometry and discuss important design parameters for realization of intersubband detectors. Key advantages with the proposed design include large degree of freedom in choice of materials compositions, possible enhanced optical resonance effects due to periodically ordered NW arrays and the compatibility with silicon substrates. We believe that the proposed detector design offers the route towards monolithic integration of compact and sensitive III-V NW long wavelength detectors with Si technology.Keywords: intersubband photodetector, infrared, nanowire, quantum disc
Procedia PDF Downloads 386