Search results for: integrated security
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5657

Search results for: integrated security

1577 Equality in Higher Education: A Library and Learning Collaborative Project to Support Teachers

Authors: Ika Jorum

Abstract:

The aim of this collaborative project was to develop library support that contributes in a long-term way to a technical university’s work on increased equality in education. The background was an assessment made by the Higher Education Authority that showed the need for improvement regarding equality in several programs at the university. The university’s Vice President for equality and Vice President for sustainability announced funds for projects that supported the improvement of equality in education. The library was granted funding for a one-year project that aimed both to support teachers in order to embed equality in education and to support the library staff and improve the organization’s own work. The part of the project that was directed to teachers was performed as activities in different areas and forms, such as acquisition and collections, teaching, exhibitions and book discussions. Besides the activities and support that was offered to teachers, the education team had journal clubs in order to develop and embed equality in their own teaching. The part that was directed to library staff and management was performed as workshops in collaboration with Equality Office in order to identify areas where the library could make improvements on work with equality and inclusion. The expectation was that the activities would be well attended since the project team had got indications that the content would be relevant. The outcome of this project was that some activities turned out to be more attended than others and what is expected to be found relevant, for example, a workshop on information searching from a gender and equality perspective for teachers, might still not attract participants. On the other hand, Ph.D. students and students participated in the book discussions and wanted them to continue after the project had ended. Results will be shared both on what was successful and what was challenging. Some reflections will be given on what can be done to attract participants to activities in the area of gender equality that is most likely relevant for the expected attendants and how results from a project on gender equality can be integrated into an organization’s daily work.

Keywords: equality, higher education, critical information literacy, collaboration

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1576 Enhancing Cognitive and Emotional Well-Being in an 85-Year-Old American-Dominican Veteran through Neuropsychological Intervention and Cognitive Stimulation

Authors: Natividad Natalia Angeles Manuel

Abstract:

In the Dominican Republic, American-Dominican veterans face unique challenges due to their dual identities and wartime experiences. This case study examines an 85-year-old veteran with memory impairments and emotional distress linked to military service. A neuropsychological assessment using standardized tools evaluated cognitive domains and functional abilities. Significant deficits in memory, orientation, semantic memory, and executive functions, alongside symptoms of Post-Traumatic Stress Disorder and depression, were identified. A six-month cognitive stimulation program included tailored interventions to enhance memory, attention, and executive skills through weekly sessions and group activities. Medical and physical therapy support aimed to improve overall cognitive, functional, and emotional outcomes. Follow-up evaluations showed improvements in memory retention, attention, task proficiency, and reduced depressive symptoms, highlighting the program's effectiveness in promoting emotional well-being and quality of life. Despite ongoing memory challenges and military-related nightmares, the veteran responded positively to interventions, demonstrating resilience and motivation. This study emphasizes the importance of personalized neuropsychological interventions for American-Dominican veterans in the Dominican Republic. Through assessment tools and focused cognitive stimulation strategies, healthcare providers can successfully alleviate cognitive and emotional challenges stemming from traumatic experiences in elderly veterans. Overall, integrated neuropsychological assessment and stimulation programs are shown to enhance cognitive resilience and emotional well-being, thus contributing to an enhanced quality of life for aging American-Dominican veterans.

Keywords: neuropsychology, cognitive stimulation, American-Dominican veterans, Dominican Republic, PTSD, memory deficits

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1575 The Impact of Intelligent Control Systems on Biomedical Engineering and Research

Authors: Melkamu Tadesse Getachew

Abstract:

Intelligent control systems have revolutionized biomedical engineering, advancing research and enhancing medical practice. This review paper examines the impact of intelligent control on various aspects of biomedical engineering. It analyzes how these systems enhance precision and accuracy in biomedical instrumentation, improving diagnostics, monitoring, and treatment. Integration challenges are addressed, and potential solutions are proposed. The paper also investigates the optimization of drug delivery systems through intelligent control. It explores how intelligent systems contribute to precise dosing, targeted drug release, and personalized medicine. Challenges related to controlled drug release and patient variability are discussed, along with potential avenues for overcoming them. The comparison of algorithms used in intelligent control systems in biomedical control is also reviewed. The implications of intelligent control in computational and systems biology are explored, showcasing how these systems enable enhanced analysis and prediction of complex biological processes. Challenges such as interpretability, human-machine interaction, and machine reliability are examined, along with potential solutions. Intelligent control in biomedical engineering also plays a crucial role in risk management during surgical operations. This section demonstrates how intelligent systems improve patient safety and surgical outcomes when integrated into surgical robots, augmented reality, and preoperative planning. The challenges associated with these implementations and potential solutions are discussed in detail. In summary, this review paper comprehensively explores the widespread impact of intelligent control on biomedical engineering, showing the future of human health issues promising. It discusses application areas, challenges, and potential solutions, highlighting the transformative potential of these systems in advancing research and improving medical practice.

Keywords: Intelligent control systems, biomedical instrumentation, drug delivery systems, robotic surgical instruments, Computational monitoring and modeling

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1574 Bamboo as the Frontier for Economically Sustainable Solution to Flood Control and Human Wildlife Conflict

Authors: Nirman Kumar Ojha

Abstract:

Bamboo plantation can be integrated for natural embankment against flood and live fencing against wild animals, at the same time provide economic opportunity for the poor farmers as a sustainable solution and adaptation alternative. 2010 flood in the Rui River completely inundated fields of four VDCs in Madi, Chitwan National Park with extensive bank erosion. The main aim of this action research was to identify an economically sustainable natural embankment against flood and also providing wildlife friendly fencing to reduce human-wildlife conflict. Community people especially poor farmers were trained for soil testing, land identification, plantation, and the harvesting regime, nursery set up and intercropping along with bamboo plantation on the edge of the river bank in order to reduce or minimize soil erosion. Results show that farmers are able to establish cost efficient and economically sustainable river embankment with bamboo plantation also creating a fence for wildlife which has also promoted bamboo cultivation and conservation. This action research has amalgamated flood control and wildlife control with the livelihood of the farmers which otherwise would cost huge resource. Another major impact of the bamboo plantation is its role in climate change and its adaptation process reducing degradation and improving vegetation cover contributing to landscape management. Based on this study, we conclude that bamboo plantation in Madi, Chitwan promoted the livelihood of the poor farmers providing a sustainable economic solution to reduce bank erosion, human-wildlife conflict and contributes to landscape management.

Keywords: climate change and conservation, economic opportunity, flood control, national park

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1573 U Slot Loaded Wearable Textile Antenna

Authors: Varsha Kheradiya, Ganga Prasad Pandey

Abstract:

The use of wearable antennas is rising because wireless devices become small. The wearable antenna is part of clothes used in communication applications, including energy harvesting, medical application, navigation, and tracking. In current years, Antennas embroidered on clothes, conducting antennas based on fabric, polymer embedded antennas, and inkjet-printed antennas are all attractive ways. Also shows the analysis required for wearable antennas, such as wearable antennae interacting with the human body. The primary requirements for the antenna are small size, low profile minimizing radiation absorption by the human body, high efficiency, structural integrity to survive worst situations, and good gain. Therefore, research in energy harvesting, biomedicine, and military application design is increasingly favoring flexible wearable antennas. Textile materials that are effectively used for designing and developing wearable antennas for body area networks. The wireless body area network is primarily concerned with creating effective antenna systems. The antenna should reduce their size, be lightweight, and be adaptable when integrated into clothes. When antennas integrate into clothes, it provides a convenient alternative to those fabricated using rigid substrates. This paper presents a study of U slot loaded wearable textile antenna. U slot patch antenna design is illustrated for wideband from 1GHz to 6 GHz using textile material jeans as substrate and pure copper polyester taffeta fabric as conducting material. This antenna design exhibits dual band results for WLAN at 2.4 GHz and 3.6 GHz frequencies. Also, study U slot position horizontal and vertical shifting. Shifting the horizontal positive X-axis position of the U slot produces the third band at 5.8 GHz.

Keywords: microstrip patch antenna, textile material, U slot wearable antenna, wireless body area network

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1572 Sequence Component-Based Adaptive Protection for Microgrids Connected Power Systems

Authors: Isabelle Snyder

Abstract:

Microgrid protection presents challenges to conventional protection techniques due to the low induced fault current. Protection relays present in microgrid applications require a combination of settings groups to adjust based on the architecture of the microgrid in islanded and grid-connected mode. In a radial system where the microgrid is at the other end of the feeder, directional elements can be used to identify the direction of the fault current and switch settings groups accordingly (grid connected or microgrid connected). However, with multiple microgrid connections, this concept becomes more challenging, and the direction of the current alone is not sufficient to identify the source of the fault current contribution. ORNL has previously developed adaptive relaying schemes through other DOE-funded research projects that will be evaluated and used as a baseline for this research. The four protection techniques in this study are the following: (1) Adaptive Current only Protection System (ACPS), Intentional (2) Unbalanced Control for Protection Control (IUCPC), (3) Adaptive Protection System with Communication Controller (APSCC) (4) Adaptive Model-Driven Protective Relay (AMDPR). The first two methods focus on identifying the islanded mode without communication by monitoring the current sequence component generated by the system (ACPS) or induced with inverter control during islanded mode (IUCPC) to identify the islanding condition without communication at the relay to adjust the settings. These two methods are used as a backup to the APSCC, which relies on a communication network to communicate the islanded configuration to the system components. The fourth method relies on a short circuit model inside the relay that is used in conjunction with communication to adjust the system configuration and computes the fault current and adjusts the settings accordingly.

Keywords: adaptive relaying, microgrid protection, sequence components, islanding detection, communication controlled protection, integrated short circuit model

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1571 Analysis of the Unmanned Aerial Vehicles’ Incidents and Accidents: The Role of Human Factors

Authors: Jacob J. Shila, Xiaoyu O. Wu

Abstract:

As the applications of unmanned aerial vehicles (UAV) continue to increase across the world, it is critical to understand the factors that contribute to incidents and accidents associated with these systems. Given the variety of daily applications that could utilize the operations of the UAV (e.g., medical, security operations, construction activities, landscape activities), the main discussion has been how to safely incorporate the UAV into the national airspace system. The types of UAV incidents being reported range from near sightings by other pilots to actual collisions with aircraft or UAV. These incidents have the potential to impact the rest of aviation operations in a variety of ways, including human lives, liability costs, and delay costs. One of the largest causes of these incidents cited is the human factor; other causes cited include maintenance, aircraft, and others. This work investigates the key human factors associated with UAV incidents. To that end, the data related to UAV incidents that have occurred in the United States is both reviewed and analyzed to identify key human factors related to UAV incidents. The data utilized in this work is gathered from the Federal Aviation Administration (FAA) drone database. This study adopts the human factor analysis and classification system (HFACS) to identify key human factors that have contributed to some of the UAV failures to date. The uniqueness of this work is the incorporation of UAV incident data from a variety of applications and not just military data. In addition, identifying the specific human factors is crucial towards developing safety operational models and human factor guidelines for the UAV. The findings of these common human factors are also compared to similar studies in other countries to determine whether these factors are common internationally.

Keywords: human factors, incidents and accidents, safety, UAS, UAV

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1570 The Factors That Influence the Self-Sufficiency and the Self-Efficacy Levels among Oncology Patients

Authors: Esra Danaci, Tugba Kavalali Erdogan, Sevil Masat, Selin Keskin Kiziltepe, Tugba Cinarli, Zeliha Koc

Abstract:

This study was conducted in a descriptive and cross-sectional manner to determine that factors that influence the self-efficacy and self-sufficiency levels among oncology patients. The research was conducted between January 24, 2017 and September 24, 2017 in the oncology and hematology departments of a university hospital in Turkey with 179 voluntary inpatients. The data were collected through the Self-Sufficiency/Self-Efficacy Scale and a 29-question survey, which was prepared in order to determine the sociodemographic and clinical properties of the patients. The Self-Sufficiency/Self-Efficacy Scale is a Likert-type scale with 23 articles. The scale scores range between 23 and 115. A high final score indicates a good self-sufficiency/self-efficacy perception for the individual. The data were analyzed using percentage analysis, one-way ANOVA, Mann Whitney U-test, Kruskal Wallis test and Tukey test. The demographic data of the subjects were as follows: 57.5% were male and 42.5% were female, 82.7% were married, 46.4% were primary school graduate, 36.3% were housewives, 19% were employed, 93.3% had social security, 52.5% had matching expenses and incomes, 49.2% lived in the center of the city. The mean age was 57.1±14.6. It was determined that 22.3% of the patients had lung cancer, 19.6% had leukemia, and 43.6% had a good overall condition. The mean self-sufficiency/self-efficacy score was 83,00 (41-115). It was determined that the patients' self-sufficiency/self-efficacy scores were influenced by some of their socio-demographic and clinical properties. This study has found that the patients had high self-sufficiency/self-efficacy scores. It is recommended that the nursing care plans should be developed to improve their self-sufficiency/self-efficacy levels in the light of the patients' sociodemographic and clinical properties.

Keywords: oncology, patient, self-efficacy, self-sufficiency

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1569 The Impact of Rapid Urbanisation on Public Transport Systems in the Gauteng Region of South Africa

Authors: J. Chakwizira, P. Bikam, T. A. Adeboyejo

Abstract:

This paper seeks to illustrate the impact of rapid urbanization (in terms of both increase in people and vehicles) in the Gauteng region (which includes Johannesburg, Pretoria and Ekurhuleni). The impact that existing transport systems and options place on the capacity of residents from low income areas to travel and conduct various socio-economic activities is discussed. The findings are drawn from a 2013 analysis of a random transport household survey of 1550 households carried out in Gauteng province. 91.4% of the study respondents had access to public transport, while 8.6% had no access to public transport. Of the 91.4% who used public transport, the main reason used to explain this state of affairs was that it was affordable (54.3%), convenient (15.9%), Accessible (11.9%), lack of alternatives (6.4%) and reliable at 4.1%. Recommendations advanced revolve around the need to reverse land use and transportation effects of apartheid planning, growing and developing a sustainable critical mass of public transport interventions supported by appropriate transport systems that are environmentally sustainable through proper governance. 38.5% of the respondents indicated that developing compact, smart and integrated urban land spaces was key to reducing travel challenges in the study area. 23.4% indicated that the introduction and upgrading of BRT buses to cover all areas in the study area was a step in the right direction because it has great potential in shifting travel patterns to favor public modes of transport. 15.1% indicated that all open spaces should be developed so that fragmentation of land uses can be addressed. This would help to fight disconnected and fragmented space and trip making challenges in Gauteng. 13.4% indicated that improving the metro rail services was critical since this is a mass mover of commuters. 9.6% of the respondents highlighted that the bus subsidy policy has to be retained in the short to medium term since the spatial mismatches and challenges created by apartheid are yet to be fully reversed.

Keywords: urbanisation, population, public, transport systems, Gauteng

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1568 Modeling of the Dynamic Characteristics of a Spindle with Experimental Validation

Authors: Jhe-Hao Huang, Kun-Da Wu, Wei-Cheng Shih, Jui-Pin Hung

Abstract:

This study presented the investigation on the dynamic characteristics of a spindle tool system by experimental and finite element modeling approaches. As well known facts, the machining stability is greatly determined by the dynamic characteristics of the spindle tool system. Therefore, understanding the factors affecting dynamic behavior of a spindle tooling system is a prerequisite in dominating the final machining performance of machine tool system. To this purpose, a physical spindle unit was employed to assess the dynamic characteristics by vibration tests. Then, a three-dimensional finite element model of a high-speed spindle system integrated with tool holder was created to simulate the dynamic behaviors. For modeling the angular contact bearings, a series of spring elements were introduced between the inner and outer rings. The spring constant can be represented by the contact stiffness of the rolling bearing based on Hertz theory. The interface characteristic between spindle nose and tool holder taper can be quantified from the comparison of the measurements and predictions. According to the results obtained from experiments and finite element predictions, the vibration behavior of the spindle is dominated by the bending deformation of the spindle shaft in different modes, which is further determined by the stiffness of the bearings in spindle housing. Also, the spindle unit with tool holder shows a different dynamic behavior from that of spindle without tool holder. This indicates the interface property between tool holder and spindle nose plays an dominance on the dynamic characteristics the spindle tool system. Overall, the dynamic behaviors the spindle with and without tool holder can be successfully investigated through the finite element model proposed in this study. The prediction accuracy is determined by the modeling of the rolling interface of ball bearings in spindles and the interface characteristics between tool holder and spindle nose. Besides, identifications of the interface characteristics of a ball bearing and spindle tool holder are important for the refinement of the spindle tooling system to achieve the optimum machining performance.

Keywords: contact stiffness, dynamic characteristics, spindle, tool holder interface

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1567 Revisiting Pedestrians’ Appraisals of Urban Streets

Authors: Norhaslina Hassan, Sherina Rezvanipour, Amirhosein Ghaffarian Hoseini, Ng Siew Cheok

Abstract:

The walkability features of urban streets are prominent factors that are often focused on achieving a pedestrian-friendly environment. The limited attention that walkability enhancements devote to pedestrians' experiences or perceptions, on the other hand, raises the question of whether walkability enhancement is sufficient for pedestrians to enjoy using the streets. Thus, this paper evaluates the relationship between the socio-physical components of urban streets and pedestrians’ perceptions. A total of 1152 pedestrians from five urban streets in two major Malaysian cities, Kuala Lumpur, and George Town, Penang, participated in this study. In particular, this study used pedestrian preference scores towards socio-physical attributes that exist in urban streets to assess their impact on pedestrians’ appraisals of street likeability, comfort, and safety. Through analysis, the principal component analysis extracted eight socio-physical components, which were then tested via an ordinal regression model to identify their impact on pedestrian street likeability, comfort (visual, auditory, haptic and olfactory), and safety (physical safety, environmental safety, and security). Furthermore, a non-parametric Kruskal Wallis test was used to identify whether the results were subjected to any socio-demographic differences. The results found that all eight components had some degree of effect on the appraisals. It was also revealed that pedestrians’ preferences towards the attributes as well as their appraisals significantly varied based on their age, gender, ethnicity and education. These results and their implications for urban planning are further discussed in this paper.

Keywords: pedestrian appraisal, pedestrian perception, street sociophysical attributes, walking experience

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1566 BIM4Cult Leveraging BIM and IoT for Enhancing Fire Safety in Historical Buildings

Authors: Anastasios Manos, Despina Elisabeth Filippidou

Abstract:

Introduction: Historical buildings are an inte-gral part of the cultural heritage of every place, and beyond the obvious need for protection against risks, they have specific requirements regarding the handling of hazards and disasters such as fire, floods, earthquakes, etc. Ensuring high levels of protection and safety for these buildings is impera-tive for two distinct but interconnected reasons: a) they themselves constitute cultural heritage, and b) they are often used as museums/cultural spaces, necessitating the protection of both human life (vis-itors and workers) and the cultural treasures they house. However, these buildings present serious constraints in implementing the necessary measures to protect them from destruction due to their unique architecture, construction methods, and/or the structural materials used in the past, which have created an existing condition that is sometimes challenging to reshape and operate within the framework of modern regulations and protection measures. One of the most devastating risks that threaten historical buildings is fire. Catastrophic fires demonstrate the need for timely evaluation of fire safety measures in historical buildings. Recog-nizing the criticality of protecting historical build-ings from the risk of fire, the Confederation of Fire Protection Associations in Europe (CFPA E) issued specific guidelines in 2013 (CFPA-E Guideline No 30:2013 F) for the fire protection of historical buildings at the European level. However, until now, few actions have been implemented towards leveraging modern technologies in the field of con-struction and maintenance of buildings, such as Building Information Modeling (BIM) and the Inter-net of Things (IoT), for the protection of historical buildings from risks like fires, floods, etc. The pro-ject BIM4Cult has bee developed in order to fill this gap. It is a tool for timely assessing and monitoring of the fire safety level of historical buildings using BIM and IoT technologies in an integrated manner. The tool serves as a decision support expert system for improving the fire safety of historical buildings by continuously monitoring, controlling and as-sessing critical risk factors for fire.

Keywords: Iot, fire, BIM, expert system

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1565 Urban Ecotourism Development in Borderlands: An Exploratory Study of Xishuangbanna Dai Autonomous Prefecture, China

Authors: Min Liu, Thanapauge Chamaratana

Abstract:

Integrating ecotourism into urban borderlands holds significant potential for promoting sustainable development, enhancing cross-border cooperation, and preserving cultural and natural heritage. This study aims to evaluate the current status and strategic measures for sustainable ecotourism development in the border urban areas of Xishuangbanna, leveraging the unique opportunities and challenges presented by its policy and geographical location. Employing a qualitative research approach, the exploratory study utilizes documentary research, observation, and in-depth interviews with 20 key stakeholders, including local government officials, tourism operators, community members, and tourists. Content analysis is conducted to interpret the collected data. The findings reveal that Xishuangbanna holds significant potential for ecotourism due to its rich biodiversity, cultural heritage, and strategic location along the Belt and Road Initiative route. The integration of ecotourism can drive economic growth, create employment opportunities, and foster a deeper appreciation for conservation efforts. By promoting ecotourism practices, the region can attract environmentally conscious travelers, thereby contributing to global sustainability goals. However, challenges such as inadequate infrastructure, limited community involvement, and environmental concerns are also identified. The study recommends enhancing ecotourism development in urban borderlands through integrated planning, stakeholder collaboration, and sustainable practices. These measures are essential to ensure long-term benefits for both the local community and the environment. Moreover, the study underscores the importance of a holistic approach to ecotourism development, which balances economic, social, and environmental priorities to achieve sustainable outcomes for urban borderlands.

Keywords: ecotourism, sustainable tourism, urban, borderland

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1564 The Advancement of Environmental Impact Assessment for 5th Transmission Natural Gas Pipeline Project in Thailand

Authors: Penrug Pengsombut, Worawut Hamarn, Teerawuth Suwannasri, Kittiphong Songrukkiat, Kanatip Ratanachoo

Abstract:

PTT Public Company Limited or simply PTT has played an important role in strengthening national energy security of the Kingdom of Thailand by transporting natural gas to customers in power, industrial and commercial sectors since 1981. PTT has been constructing and operating natural gas pipeline system of over 4,500-km network length both onshore and offshore laid through different area classifications i.e., marine, forest, agriculture, rural, urban, and city areas. During project development phase, an Environmental Impact Assessment (EIA) is conducted and submitted to the Office of Natural Resources and Environmental Policy and Planning (ONEP) for approval before project construction commencement. Knowledge and experiences gained and revealed from EIA in the past projects definitely are developed to further advance EIA study process for newly 5th Transmission Natural Gas Pipeline Project (5TP) with approximately 415 kilometers length. The preferred pipeline route is selected and justified by SMARTi map, an advance digital one-map platform with consists of multiple layers geographic and environmental information. Sensitive area impact focus (SAIF) is a practicable impact assessment methodology which appropriate for a particular long distance infrastructure project such as 5TP. An environmental modeling simulation is adopted into SAIF methodology for impact quantified in all sensitive areas whereas other area along pipeline right-of-ways is typically assessed as an impact representative. Resulting time and cost deduction is beneficial to project for early start.

Keywords: environmental impact assessment, EIA, natural gas pipeline, sensitive area impact focus, SAIF

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1563 Efficient Fuzzy Classified Cryptographic Model for Intelligent Encryption Technique towards E-Banking XML Transactions

Authors: Maher Aburrous, Adel Khelifi, Manar Abu Talib

Abstract:

Transactions performed by financial institutions on daily basis require XML encryption on large scale. Encrypting large volume of message fully will result both performance and resource issues. In this paper a novel approach is presented for securing financial XML transactions using classification data mining (DM) algorithms. Our strategy defines the complete process of classifying XML transactions by using set of classification algorithms, classified XML documents processed at later stage using element-wise encryption. Classification algorithms were used to identify the XML transaction rules and factors in order to classify the message content fetching important elements within. We have implemented four classification algorithms to fetch the importance level value within each XML document. Classified content is processed using element-wise encryption for selected parts with "High", "Medium" or “Low” importance level values. Element-wise encryption is performed using AES symmetric encryption algorithm and proposed modified algorithm for AES to overcome the problem of computational overhead, in which substitute byte, shift row will remain as in the original AES while mix column operation is replaced by 128 permutation operation followed by add round key operation. An implementation has been conducted using data set fetched from e-banking service to present system functionality and efficiency. Results from our implementation showed a clear improvement in processing time encrypting XML documents.

Keywords: XML transaction, encryption, Advanced Encryption Standard (AES), XML classification, e-banking security, fuzzy classification, cryptography, intelligent encryption

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1562 The Use of TRIZ to Map the Evolutive Pattern of Products

Authors: Fernando C. Labouriau, Ricardo M. Naveiro

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This paper presents a model for mapping the evolutive pattern of products in order to generate new ideas, to perceive emerging technologies and to manage product’s portfolios in new product development (NPD). According to the proposed model, the information extracted from the patent system is filtered and analyzed with TRIZ tools to produce the input information to the NPD process. The authors acknowledge that the NPD process is well integrated within the enterprises business strategic planning and that new products are vital in the competitive market nowadays. In the other hand, it has been observed the proactive use of patent information in some methodologies for selecting projects, mapping technological change and generating product concepts. And one of these methodologies is TRIZ, a theory created to favor innovation and to improve product design that provided the analytical framework for the model. Initially, it is presented an introduction to TRIZ mainly focused on the patterns of evolution of technical systems and its strategic uses, a brief and absolutely non-comprehensive description as the theory has several others tools being widely employed in technical and business applications. Then, it is introduced the model for mapping the products evolutive pattern with its three basic pillars, namely patent information, TRIZ and NPD, and the methodology for implementation. Following, a case study of a Brazilian bike manufacturing is presented to proceed the mapping of a product evolutive pattern by decomposing and analyzing one of its assemblies along ten evolution lines in order to envision opportunities for further product development. Some of these lines are illustrated in more details to evaluate the features of the product in relation to the TRIZ concepts using a comparison perspective with patents in the state of the art to validate the product’s evolutionary potential. As a result, the case study provided several opportunities for a product improvement development program in different project categories, identifying technical and business impacts as well as indicating the lines of evolution that can mostly benefit from each opportunity.

Keywords: product development, patents, product strategy, systems evolution

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1561 The Use of Allelopathic Influences of Auxiliary Plants in the Bioproduction of Tomatoes

Authors: Demur Bakuradze, Mzia Beruashvili

Abstract:

It is known that bioactive compounds that are secreted by allelopathic plants sown with the main culture and are natural phytotoxic substances can be used as natural pesticides that, unlike synthetic agrochemicals, are less likely to disrupt the global ecosystem. Alternative plant protection approaches to date include components of integrated pest management programs and natural plant protection tools. Every year, more and more evidence is given on the successful use of these means, including allelopathic compounds in plant protection against pests. Proper use of these interactions between plants and other organisms can become a serious alternative to synthetic pesticides. Due to the relevance of the issue, the purpose of the study was to study the impact of some companion allelopathic plants on the Tomato culture (variety ‘Kharisgula’) on the test plot of the Tsilkani Base Bioagricultural Service of the Agricultural Research Center (East Georgia) and the village of Kharagauli. The study was conducted in 2023-2024 with methods adopted in organic agriculture and plant protection. Various companion plants were studied: Basil (Ocimum basilicum L.), Imeretian saffron or marigold (Tagetes patula L.) and beans (Phaseolus vulgaris L.) (variety ‘Tsanava’) affects tomato culture in mixed crops. It was established that when sowing basil in rows and on the perimeter, the yield in the Tsilkani increased by 39.7%, and in Sagandzile - 42.8%. In the case of Imeretian saffron, economic efficiency in Tsilkani reached 29.5%, in Sagandzile - 28.5%, while the difference in the bean variant with the control was 31.7% in Tsilkani, and in Sagandzile - 23.8%. The study also found that when sowing aromatic plants (basil, marigold) with tomato, the number and spread of pests is quite decreasing compared to the control. In particular, the number of green vegetable bugs (Nezara viridula L.) decreased by 59.4% compared to control.

Keywords: allelopathy, companion planting, tomato, bioproduction

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1560 Innovations for Freight Transport Systems

Authors: M. Lu

Abstract:

The paper presents part of the results of EU-funded projects: SoCool@EU (Sustainable Organisation between Clusters Of Optimized Logistics @ Europe), DG-RTD (Research and Innovation), Regions of Knowledge Programme (FP7-REGIONS-2011-1). It will provide an in-depth review of emerging technologies for further improving urban mobility and freight transport systems, such as (information and physical) infrastructure, ICT-based Intelligent Transport Systems (ITS), vehicles, advanced logistics, and services. Furthermore, the paper will provide an analysis of the barriers and will review business models for the market uptake of innovations. From a perspective of science and technology, the challenges of urbanization could be mainly handled through adequate (human-oriented) solutions for urban planning, sustainable energy, the water system, building design and construction, the urban transport system (both physical and information aspects), and advanced logistics and services. Implementation of solutions for these domains should be follow a highly integrated and balanced approach, a silo approach should be avoided. To develop a sustainable urban transport system (for people and goods), including inter-hubs and intra-hubs, a holistic view is needed. To achieve a sustainable transport system for people and goods (in terms of cost-effectiveness, efficiency, environment-friendliness and fulfillment of the mobility, transport and logistics needs of the society), a proper network and information infrastructure, advanced transport systems and operations, as well as ad hoc and seamless services are required. In addition, a road map for an enhanced urban transport system until 2050 will be presented. This road map aims to address the challenges of urban transport, and to provide best practices in inter-city and intra-city environments from various perspectives, including policy, traveler behaviour, economy, liability, business models, and technology.

Keywords: synchromodality, multimodal transport, logistics, Intelligent Transport Systems (ITS)

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1559 Homogenization of Cocoa Beans Fermentation to Upgrade Quality Using an Original Improved Fermenter

Authors: Aka S. Koffi, N’Goran Yao, Philippe Bastide, Denis Bruneau, Diby Kadjo

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Cocoa beans (Theobroma cocoa L.) are the main components for chocolate manufacturing. The beans must be correctly fermented at first. Traditional process to perform the first fermentation (lactic fermentation) often consists in confining cacao beans using banana leaves or a fermentation basket, both of them leading to a poor product thermal insulation and to an inability to mix the product. Box fermenter reduces this loss by using a wood with large thickness (e>3cm), but mixing to homogenize the product is still hard to perform. Automatic fermenters are not rentable for most of producers. Heat (T>45°C) and acidity produced during the fermentation by microbiology activity of yeasts and bacteria are enabling the emergence of potential flavor and taste of future chocolate. In this study, a cylindro-rotative fermenter (FCR-V1) has been built and coconut fibers were used in its structure to confine heat. An axis of rotation (360°) has been integrated to facilitate the turning and homogenization of beans in the fermenter. This axis permits to put fermenter in a vertical position during the anaerobic alcoholic phase of fermentation, and horizontally during acetic phase to take advantage of the mid height filling. For circulation of air flow during turning in acetic phase, two woven rattan with grid have been made, one for the top and second for the bottom of the fermenter. In order to reduce air flow during acetic phase, two airtight covers are put on each grid cover. The efficiency of the turning by this kind of rotation, coupled with homogenization of the temperature, caused by the horizontal position in the acetic phase of the fermenter, contribute to having a good proportion of well-fermented beans (83.23%). In addition, beans’pH values ranged between 4.5 and 5.5. These values are ideal for enzymatic activity in the production of the aromatic compounds inside beans. The regularity of mass loss during all fermentation makes it possible to predict the drying surface corresponding to the amount being fermented.

Keywords: cocoa fermentation, fermenter, microbial activity, temperature, turning

Procedia PDF Downloads 259
1558 Towards Carbon-Free Communities: A Compilation of Urban Design Criteria for Sustainable Neighborhoods

Authors: Atefeh Kalantari

Abstract:

The increase in population and energy consumption has caused environmental crises such as the energy crisis, increased pollution, and climate change, all of which have resulted in a decline in the quality of life, especially in urban environments. Iran is one of the developing countries which faces several challenges concerning energy use and environmental sustainability such as air pollution, climate change, and energy security. On the other hand, due to its favorable geographic characteristics, Iran has diverse and accessible renewable sources, which provide appropriate substitutes to reduce dependence on fossil fuels. Sustainable development programs and post-carbon cities rely on implementing energy policies in different sectors of society, particularly, the built environment sector is one of the main ones responsible for energy consumption and carbon emissions for cities. Because of this, several advancements and programs are being implemented to promote energy efficiency for urban planning, and city experts, like others, are looking for solutions to deal with these problems. Among the solutions provided for this purpose, low-carbon design can be mentioned. Among the different scales, the neighborhood can be mentioned as a suitable scale for applying the principles and solutions of low-carbon urban design; Because the neighborhood as a "building unit of the city" includes elements and flows that all affect the number of CO2 emissions. The article aims to provide criteria for designing a low-carbon and carbon-free neighborhood through descriptive methods and secondary data analysis. The ultimate goal is to promote energy efficiency and create a more resilient and livable environment for local residents.

Keywords: climate change, low-carbon urban design, carbon-free neighborhood, resilience

Procedia PDF Downloads 74
1557 Enhancement of Aircraft Longitudinal Stability Using Tubercles

Authors: Muhammad Umer, Aishwariya Giri, Umaiyma Rakha

Abstract:

Mimicked from the humpback whale flippers, the application of tubercle technology is seen to be particularly advantageous at high angles of attack. This particular advantage is of paramount importance when it comes to structures producing lift at high angles of attack. This characteristic of the technology makes it ideal for horizontal stabilizers and selecting the same as the subject of study to identify and exploit the advantage highlighted by researchers on airfoils, this project aims in establishing a foundation for the application of the bio-mimicked technology on an existing aircraft. Using a baseline and 2 tubercle configuration integrated models, the project targets to achieve the twin aim of highlighting the possibility and merits over the base model and also choosing the right configuration in providing the best characteristic suitable for high angles of attack. To facilitate this study, the required models are generated using Solidworks followed by trials in a virtual aerodynamic environment using Fluent in Ansys for resolving the project objectives. Following a structured plan, the aim is to initially identify the advantages mathematically and then selecting the optimal configuration, simulate the end configuration at angles mimicking the actual operation envelope for the particular structure. Upon simulating the baseline configuration at various angles of attack, the stall angle was determined to be 22 degrees. Thus, the tubercle configurations will be simulated and compared at 4 different angles of attacks: 0, 10, 20, and 24. Further, after providing the optimum configuration of horizontal stabilizers, this study aims at the integration of aircraft structure so that the results better imply the end deliverables of real life application. This draws the project scope closer at this point into longitudinal static stability considerations and improvements in the manoeuvrability characteristics. The objective of the study is to achieve a complete overview ready for real life application with marked benefits obtainable from bio morphing of the tubercle technology.

Keywords: flow simulation, horizontal stabilizer, stability enhancement, tubercle

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1556 Linearly Polarized Single Photon Emission from Nonpolar, Semipolar and Polar Quantum Dots in GaN/InGaN Nanowires

Authors: Snezana Lazic, Zarko Gacevic, Mark Holmes, Ekaterina Chernysheva, Marcus Müller, Peter Veit, Frank Bertram, Juergen Christen, Yasuhiko Arakawa, Enrique Calleja

Abstract:

The study reports how the pencil-like morphology of a homoepitaxially grown GaN nanowire can be exploited for the fabrication of a thin conformal InGaN nanoshell, hosting nonpolar, semipolar and polar single photon sources (SPSs). All three SPS types exhibit narrow emission lines (FWHM~0.35 - 2 meV) and high degrees of linear optical polarization (P > 70%) in the low-temperature micro-photoluminescence (µ-PL) experiments and are characterized by a pronounced antibunching in the photon correlation measurements (gcorrected(2)(0) < 0.3). The quantum-dot-like exciton localization centers induced by compositional fluctuations within the InGaN nanoshell are identified as the driving mechanism for the single photon emission. As confirmed by the low-temperature transmission electron microscopy combined with cathodoluminescence (TEM-CL) study, the crystal region (i.e. non-polar m-, semi-polar r- and polar c-facets) hosting the single photon emitters strongly affects their emission wavelength, which ranges from ultra-violet for the non-polar to visible for the polar SPSs. The photon emission lifetime is also found to be facet-dependent and varies from sub-nanosecond time scales for the non- and semi-polar SPSs to a few nanoseconds for the polar ones. These differences are mainly attributed to facet-dependent indium content and electric field distribution across the hosting InGaN nanoshell. The hereby reported pencil-like InGaN nanoshell is the first single nanostructure able to host all three types of single photon emitters and is thus a promising building block for tunable quantum light devices integrated into future photonic and optoelectronic circuits.

Keywords: GaN nanowire, InGaN nanoshell, linear polarization, nonpolar, semipolar, polar quantum dots, single-photon sources

Procedia PDF Downloads 386
1555 Transforming Educational Leadership With Innovative Administrative Strategies

Authors: Kofi Nkonkonya Mpuangnan, Samantha Govender, Hlengiwe Romualda Mhlongo

Abstract:

Educational leaders are skilled architects crafting a vibrant environment where growth, creativity, and adaptability can flourish within schools. Their journey is one of transformation, urging them to explore administrative strategies that align seamlessly with evolving educational models and cater to the specific needs of students, educators, and stakeholders. Through this committed effort to innovate, they seek to enhance the effectiveness and influence of educational systems, paving the way for a more inclusive and forward-thinking educational environment. In this context, the authors explored the concept of transforming educational leadership with administrative strategies in alignment with the following research objectives. To find the strategies that can be adopted by transformation leaders to promote effective administrative practices in an educational setting and to explore the roles of educational leaders in promoting collaboration in education. To find answers to these questions, a systematic literature review underpinned by the transformational leadership model was adopted. Therefore, concepts integrated from a variety of outlets, including academic journals, conference proceedings, and reports found within SCOPUS, WoS, and IBSS databases. A search was aided using specific themes like innovative administrative practices, the roles of educational leaders, and interdisciplinary approaches to administrative practices. The process of conducting the search adhered to the five-step framework, which was subjected to inclusion and exclusion of studies. It was found that transformational leadership, agile methodologies, employee wellbeing, seminars and workshops could foster a culture of innovation and creativity among teachers and staff to transform administrative practices in education settings. It was recommended that professional development programs be organized periodically for educational leaders in educational institutions to help them revitalize their knowledge and skills in educational administration.

Keywords: educational leadership, innovative strategies, administrative practices, professional development, stakeholder engaement, student outcome

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1554 Destruction of Coastal Wetlands in Harper City-Liberia: Setting Nature against the Future Society

Authors: Richard Adu Antwako

Abstract:

Coastal wetland destruction and its consequences have recently taken the center stage of global discussions. This phenomenon is no gray area to humanity as coastal wetland-human interaction seems inevitably ingrained in the earliest civilizations, amidst the demanding use of its resources to meet their necessities. The severity of coastal wetland destruction parallels with growing civilizations, and it is against this backdrop that, this paper interrogated the causes of coastal wetland destruction in Harper City in Liberia, compared the degree of coastal wetland stressors to the non-equilibrium thermodynamic scale as well as suggested an integrated coastal zone management to address the problems. Literature complemented the primary data gleaned via global positioning system devices, field observation, questionnaire, and interviews. Multi-sampling techniques were used to generate data from the sand miners, institutional heads, fisherfolk, community-based groups, and other stakeholders. Non-equilibrium thermodynamic theory remains vibrant in discerning the ecological stability, and it would be employed to further understand the coastal wetland destruction in Harper City, Liberia and to measure the coastal wetland stresses-amplitude and elasticity. The non-equilibrium thermodynamics postulates that the coastal wetlands are capable of assimilating resources (inputs), as well as discharging products (outputs). However, the input-output relationship exceedingly stretches beyond the thresholds of the coastal wetlands, leading to coastal wetland disequilibrium. Findings revealed that the sand mining, mangrove removal, and crude dumping have transformed the coastal wetlands, resulting in water pollution, flooding, habitat loss and disfigured beaches in Harper City in Liberia. This paper demonstrates that the coastal wetlands are converted into developmental projects and agricultural fields, thus, endangering the future society against nature.

Keywords: amplitude, crude dumping, elasticity, non-equilibrium thermodynamics, wetland destruction

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1553 Cybersecurity Challenges and Solutions in ICT Management at the Federal Polytechnic, Ado-Ekiti: A Quantitative Study

Authors: Innocent Uzougbo Onwuegbuzie, Siene Elizabeth Eke

Abstract:

This study investigates cybersecurity challenges and solutions in managing Information and Communication Technology (ICT) at the Federal Polytechnic, Ado-Ekiti, South-West Nigeria. The rapid evolution of ICT has revolutionized organizational operations and impacted various sectors, including education, healthcare, and finance. While ICT advancements facilitate seamless communication, complex data analytics, and strategic decision-making, they also introduce significant cybersecurity risks such as data breaches, ransomware, and other malicious attacks. These threats jeopardize the confidentiality, integrity, and availability of information systems, necessitating robust cybersecurity measures. The primary aim of this research is to identify prevalent cybersecurity challenges in ICT management, evaluate their impact on the institution's operations, and assess the effectiveness of current cybersecurity solutions. Adopting a quantitative research approach, data was collected through surveys and structured questionnaires from students, staff, and IT professionals at the Federal Polytechnic, Ado-Ekiti. The findings underscore the critical need for continuous investment in cybersecurity technologies, employee and student training, and regulatory compliance to mitigate evolving cyber threats. This research contributes to bridging the knowledge gap in cybersecurity management and provides valuable insights into effective strategies and technologies for safeguarding ICT systems in educational institutions. The study's objectives are to enhance the security posture of the Federal Polytechnic, Ado-Ekiti, in an increasingly digital world by identifying and addressing the cybersecurity challenges faced by its ICT management.

Keywords: cybersecurity challenges, cyber threat mitigation, federal polytechnic Ado-Ekiti, ICT management

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1552 Social Crises and Its Impact on the Environment: Case Study of Jos, Plateau State

Authors: A. B. Benshak, M. G. Yilkangnha, V. Y. Nanle

Abstract:

Social crises and violent conflict can inflict direct (short-term) impact on the environment like poisoning water bodies, climate change, deforestation, destroying the chemical component of the soil due to the chemical and biological weapons used. It can also impact the environment indirectly (long-term), e.g., the destruction of political and economic infrastructure to manage the environmental resources and breaking down traditional conservation practices, population displacement and refugee flows which puts pressure on the already inadequate resources, infrastructure, facilities, amenities, services etc. This study therefore examines the impact of social crises on the environment in Jos Plateau State with emphasis on the long-term impact, analyze the relationship between crises and the environment and assess the perception of people on social crises because much work have concentrated on other repercussions such as the economy, health etc that are more politically expedient. The data for this research were collected mostly through interviews, questionnaire, dailies and reports on the subject matter. The data and findings were presented in tables and results showed that the environment is directly and indirectly impacted by crises and that these impacts can in turn result to a continuous cycle of violent activities if not addressed because of the inadequacies in the supply of infrastructural facilities, resources and so on caused by the inflow of displaced population. Recommendations were made on providing security to minimize conflict occurrences in Jos and its environs, minimizing the impact of social crises on the environment, provision of adequate infrastructural facilities to carter for population rise, renewal and regeneration schemes, etc. which will go a long way in mitigating the impact of crises on the environment.

Keywords: environment, impact, long-term, social crises

Procedia PDF Downloads 338
1551 Examining the Development of Complexity, Accuracy and Fluency in L2 Learners' Writing after L2 Instruction

Authors: Khaled Barkaoui

Abstract:

Research on second-language (L2) learning tends to focus on comparing students with different levels of proficiency at one point in time. However, to understand L2 development, we need more longitudinal research. In this study, we adopt a longitudinal approach to examine changes in three indicators of L2 ability, complexity, accuracy, and fluency (CAF), as reflected in the writing of L2 learners when writing on different tasks before and after a period L2 instruction. Each of 85 Chinese learners of English at three levels of English language proficiency responded to two writing tasks (independent and integrated) before and after nine months of English-language study in China. Each essay (N= 276) was analyzed in terms of numerous CAF indices using both computer coding and human rating: number of words written, number of errors per 100 words, ratings of error severity, global syntactic complexity (MLS), complexity by coordination (T/S), complexity by subordination (C/T), clausal complexity (MLC), phrasal complexity (NP density), syntactic variety, lexical density, lexical variation, lexical sophistication, and lexical bundles. Results were then compared statistically across tasks, L2 proficiency levels, and time. Overall, task type had significant effects on fluency and some syntactic complexity indices (complexity by coordination, structural variety, clausal complexity, phrase complexity) and lexical density, sophistication, and bundles, but not accuracy. L2 proficiency had significant effects on fluency, accuracy, and lexical variation, but not syntactic complexity. Finally, fluency, frequency of errors, but not accuracy ratings, syntactic complexity indices (clausal complexity, global complexity, complexity by subordination, phrase complexity, structural variety) and lexical complexity (lexical density, variation, and sophistication) exhibited significant changes after instruction, particularly for the independent task. We discuss the findings and their implications for assessment, instruction, and research on CAF in the context of L2 writing.

Keywords: second language writing, Fluency, accuracy, complexity, longitudinal

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1550 Understanding the Endogenous Impact of Tropical Cyclones Floods and Sustainable Landscape Management Innovations on Farm Productivity in Malawi

Authors: Innocent Pangapanga, Eric Mungatana

Abstract:

Tropical cyclones–related floods (TCRFs) in Malawi have devastating effects on smallholder agriculture, thereby threatening the food security agenda, which is already constrained by poor agricultural innovations, low use of improved varieties, and unaffordable inorganic fertilizers, and fragmenting landholding sizes. Accordingly, households have engineered and indigenously implemented sustainable landscape management (SLM) innovations to contain the adverse effects of TCRFs on farm productivity. This study, therefore, interrogated the efficacy of SLM adoption on farm productivity under varying TCRFs, while controlling for the potential selection bias and unobservable heterogeneity through the application of the Endogenous Switching Regression Model. In this study, we further investigated factors driving SLM adoption. Substantively, we found TCRFs reducing farm productivity by 31 percent, on the one hand, and influencing the adoption of SLM innovations by 27 percent, on the other hand. The study also observed that households that interacted SLM with TCRFs were more likely to enhance farm productivity by 24 percent than their counterparts. Interestingly, the study results further demonstrated that multiple adoptions of SLM-related innovations, including intercropping, agroforestry, and organic manure, enhanced farm productivity by 126 percent, suggesting promoting SLM adoption as a package to appropriately inform existing sustainable development goals’ agricultural productivity initiatives under intensifying TCRFs in the country.

Keywords: tropical cyclones–related floods, sustainable landscape management innovations, farm productivity, endogeneity, endogenous switching regression model, panel data, smallholder agriculture

Procedia PDF Downloads 113
1549 Error Detection and Correction for Onboard Satellite Computers Using Hamming Code

Authors: Rafsan Al Mamun, Md. Motaharul Islam, Rabana Tajrin, Nabiha Noor, Shafinaz Qader

Abstract:

In an attempt to enrich the lives of billions of people by providing proper information, security and a way of communicating with others, the need for efficient and improved satellites is constantly growing. Thus, there is an increasing demand for better error detection and correction (EDAC) schemes, which are capable of protecting the data onboard the satellites. The paper is aimed towards detecting and correcting such errors using a special algorithm called the Hamming Code, which uses the concept of parity and parity bits to prevent single-bit errors onboard a satellite in Low Earth Orbit. This paper focuses on the study of Low Earth Orbit satellites and the process of generating the Hamming Code matrix to be used for EDAC using computer programs. The most effective version of Hamming Code generated was the Hamming (16, 11, 4) version using MATLAB, and the paper compares this particular scheme with other EDAC mechanisms, including other versions of Hamming Codes and Cyclic Redundancy Check (CRC), and the limitations of this scheme. This particular version of the Hamming Code guarantees single-bit error corrections as well as double-bit error detections. Furthermore, this version of Hamming Code has proved to be fast with a checking time of 5.669 nanoseconds, that has a relatively higher code rate and lower bit overhead compared to the other versions and can detect a greater percentage of errors per length of code than other EDAC schemes with similar capabilities. In conclusion, with the proper implementation of the system, it is quite possible to ensure a relatively uncorrupted satellite storage system.

Keywords: bit-flips, Hamming code, low earth orbit, parity bits, satellite, single error upset

Procedia PDF Downloads 125
1548 A Low Cost Gain-Coupled Distributed Feedback Laser Based on Periodic Surface p-Contacts

Authors: Yongyi Chen, Li Qin, Peng Jia, Yongqiang Ning, Yun Liu, Lijun Wang

Abstract:

The distributed feedback (DFB) lasers are indispensable in optical phase array (OPA) used for light detection and ranging (LIDAR) techniques, laser communication systems and integrated optics, thanks to their stable single longitudinal mode and narrow linewidth properties. Traditional index-coupled (IC) DFB lasers with uniform gratings have an inherent problem of lasing two degenerated modes. Phase shifts are usually required to eliminate the mode degeneration, making the grating structure complex and expensive. High-quality antireflection (AR) coatings on both lasing facets are also essential owing to the random facet phases introduced by the chip cleavage process, which means half of the lasing energy is wasted. Gain-coupled DFB (GC-DFB) lasers based on the periodic gain (or loss) are announced to have single longitudinal mode as well as capable of the unsymmetrical coating to increase lasing power and efficiency thanks to facet immunity. However, expensive and time-consuming technologies such as epitaxial regrowth and nanoscale grating processing are still required just as IC-DFB lasers, preventing them from practical applications and commercial markets. In this research, we propose a low-cost, single-mode regrowth-free GC-DFB laser based on periodic surface p-contacts. The gain coupling effect is achieved simply by periodic current distribution in the quantum well caused by periodic surface p-contacts, introducing very little index-coupling effect that can be omitted. It is prepared by i-line lithography, without nanoscale grating fabrication or secondary epitaxy. Due to easy fabrication techniques, it provides a method to fabricate practical low cost GC-DFB lasers for widespread practical applications.

Keywords: DFB laser, gain-coupled, low cost, periodic p-contacts

Procedia PDF Downloads 127